KR20200086625A - Method and apparatus for data processing in wireless communication system - Google Patents

Abstract

The present invention relates to a method for processing data in a wireless communication system and a device thereof. According to one embodiment of the present invention, the method comprises the steps of: determining whether to divide by determining whether data received from an upper layer device has a size, which may be processed by the layer device receiving the data; dividing the data when the data is determined to be divided; and processing the data by separating divided first data, last data, and intermediate data. According to an embodiment of the present invention, a service may be effectively provided in a mobile communication system.

Description

METHOD AND APPARATUS FOR DATA PROCESSING IN A WIRELESS COMMUNICATION SYSTEM

The present disclosure relates to a method and apparatus for processing data in a wireless communication system.

Efforts have been made to develop an improved 5G communication system or a pre-5G communication system to meet the increasing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, a 5G communication system or a pre-5G communication system is called a 4G network (Beyond 4G Network) communication system or an LTE system (Post LTE) or later system. The 5G communication system established by 3GPP is called a New Radio (NR) system. To achieve high data rates, 5G communication systems are contemplated for implementation in the ultra-high frequency (mmWave) band (eg, 60 gigabit (60 GHz) band). In order to mitigate path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, in 5G communication systems, beamforming, massive array multiple input/output (massive MIMO), full dimensional multiple input/output (FD-MIMO) ), array antenna, analog beam-forming, and large scale antenna techniques have been discussed and applied to NR systems. In addition, in order to improve the network of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network , Device to Device communication (D2D), wireless backhaul, mobile network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation Technology development is being made. In addition, in the 5G system, advanced coding modulation (Advanced Coding Modulation (ACM)) hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC), advanced access technology FBMC (Filter Bank Multi Carrier), NOMA (non-orthogonal multiple access), and SCMA (sparse code multiple access) are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network in which humans generate and consume information, to an Internet of Things (IoT) network that exchanges information between distributed components such as objects. Internet of Everything (IoE) technology, in which big data processing technology, etc. through connection to a cloud server, is combined with IoT technology is also emerging. In order to implement IoT, technical elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between objects, a machine to machine (Machine to Machine) , M2M), MTC (Machine Type Communication) and other technologies are being studied. In the IoT environment, an intelligent IT (Internet Technology) service that collects and analyzes data generated from connected objects to create new values in human life may be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, high-tech medical service through convergence and combination between existing IT (iInformation Technology) technology and various industries. It can be applied to.

Accordingly, various attempts have been made to apply a 5G communication system to an IoT network. For example, 5G communication such as a sensor network, a machine to machine (M2M), and a machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antenna. It may be said that the application of cloud radio access network (cloud RAN) as the big data processing technology described above is an example of 5G technology and IoT technology convergence.

As it is possible to provide various services according to the above-mentioned and the development of a mobile communication system, a method for effectively providing these services is required.

The disclosed embodiment provides an apparatus and method capable of effectively providing a service in a mobile communication system.

In a wireless communication system according to an embodiment, a data processing method may include determining whether data received from an upper layer device is a size that can be processed by a layer device receiving the data, and determining whether or not to divide the data. If it is determined to include the step of performing data division and the step of performing data processing by dividing the divided first data, last data, and intermediate data.

According to the disclosed embodiment, it is possible to effectively provide a service in a mobile communication system.

1A is a diagram showing the structure of an LTE system to which an embodiment is applied.
1B is a diagram illustrating a radio protocol structure of an LTE system to which an embodiment is applied.
1C is a diagram showing the structure of a next-generation mobile communication system to which an embodiment is applied.
1D is a diagram illustrating a radio protocol structure of a next-generation mobile communication system to which an embodiment is applied.
1E is a diagram illustrating a procedure for establishing a connection between a terminal and a network according to an embodiment.
1F is a diagram illustrating a procedure for a base station to check a terminal's capability according to an embodiment.
1G is a diagram illustrating a first embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.
1H is a diagram illustrating a specific partitioning and reassembly method for a first embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.
FIG. 1I is a diagram illustrating a specific division and reassembly method for a second embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.
1J is a diagram illustrating a procedure for processing data when an upper layer header compression procedure or integrity protection is set according to an embodiment.
1K is a diagram illustrating a third embodiment of efficiently processing data in a PDCP layer device according to an embodiment when the first embodiment or the second embodiment is applied to a new layer device located above the PDCP layer device. .
FIG. 1L shows that when the first embodiment or the second embodiment is applied to the PDCP layer device, and the partitioning method according to an embodiment is performed before the header compression procedure or the integrity protection or encryption procedure, the PDCP layer device efficiently processes data. It is a figure showing the fourth embodiment to be processed.
FIG. 1M is a PDCP layer device in which the first embodiment or the second embodiment is applied in a PDCP layer device, and a partitioning method according to an embodiment is performed after a header compression procedure and before an integrity protection or encryption procedure. It is a figure showing a fifth embodiment for efficiently processing data.
FIG. 1N shows that when the first embodiment or the second embodiments are applied in a PDCP layer device, and a partitioning method according to an embodiment is performed after a header compression procedure or an integrity protection or encryption procedure, data from the PDCP layer device is efficiently performed. It is a figure showing the sixth embodiment to be processed.
1O is a diagram illustrating an operation of a transmitting end of a terminal for a data division method and a reassembly example of upper layer data according to an embodiment.
1P is a diagram illustrating an operation of a receiving end of a terminal for a data division method and a reassembly example of upper layer data according to an embodiment.
1Q is a block diagram showing the configuration of a terminal or a wireless node according to an embodiment.
1R is a block diagram showing the configuration of a TRP device or a wireless node in a wireless communication system according to an embodiment.
2A is a diagram showing the structure of an LTE system to which an embodiment is applied.
2B is a diagram illustrating a radio protocol structure of an LTE system to which an embodiment is applied.
2C is a diagram illustrating the structure of a next-generation mobile communication system to which an embodiment is applied.
2D is a diagram showing a radio protocol structure of a next-generation mobile communication system to which an embodiment is applied.
2E is a diagram illustrating a network structure supporting wireless backhaul considered in a next generation mobile communication system according to an embodiment.
Figure 2f is a terminal in a wireless backhaul network (IAB) of a next-generation mobile communication system according to an embodiment when a terminal establishes a connection with a wireless node (IAB node or IAB donor) or a child wireless node is a parent wireless node (IAB node or IAB donor) ) And shows the procedure for performing RRC connection establishment when establishing a connection.
2G is a diagram illustrating a protocol layer device that each wireless node may have in a next generation mobile communication system supporting wireless backhaul according to an embodiment.
2ha is a diagram illustrating a bearer management and processing method of wireless nodes in a next generation mobile communication system supporting wireless backhaul according to an embodiment.
FIG. 2HB processes different data differently according to data types in a wireless backhaul network (IAB) environment according to an embodiment of the present disclosure, or transmits or receives data by processing data with different protocol layer devices. Or it is a diagram showing the delivery procedure, and is a diagram further embodying FIG. 2ha.
2i is a security in a wireless link or a wireless section (eg, a wireless link between a terminal and a wireless node in a wireless backhaul network or between a terminal and a top-level node or a wireless node and a top-level wireless node accessed by the terminal) according to an embodiment. It is a diagram showing how to strengthen the.
FIG. 2J sets a separate upper layer device (for example, a second PDCP layer device) for integrity enhancement of the F1 interface in the wireless section in the wireless backhaul network structure according to the embodiment described in FIG. 2G and protects integrity and It is a figure for specifically describing a 2-1 embodiment for performing a verification procedure.
FIG. 2K illustrates a separate upper layer device (for example, a second PDCP layer device) for encryption and decryption for security enhancement of an F1 interface in a wireless section in a wireless backhaul network structure according to the embodiment described with reference to FIG. 2G. It is a figure specifically explaining the 2-2 embodiment for performing the procedure.
FIG. 2L is a diagram illustrating the operation of a wireless node (the highest-level wireless node or an intermediate node or terminal) according to an embodiment.
2M shows the structure of a terminal or a wireless node according to an embodiment.
2N is a block diagram showing the configuration of a TRP device or a wireless node in a wireless communication system according to an embodiment.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In describing the embodiments, descriptions of technical contents well known in the technical field to which the present disclosure pertains and which are not directly related to the present disclosure will be omitted. This is to more clearly communicate the gist of the present disclosure by omitting unnecessary descriptions.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. The same reference numbers are assigned to the same or corresponding elements in each drawing.

Advantages and features of the present disclosure, and a method of achieving them will be apparent with reference to embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, and may be implemented in various different forms, and only the embodiments allow the disclosure of the present disclosure to be complete, and common knowledge in the art to which the present disclosure pertains. It is provided to fully inform the person having the scope of the invention, and the present disclosure is only defined by the scope of the claims. The same reference numerals refer to the same components throughout the specification.

At this time, it will be understood that each block of the process flow chart diagrams and combinations of flow chart diagrams can be performed by computer program instructions. These computer program instructions may be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, so that instructions performed through a processor of a computer or other programmable data processing equipment are described in flowchart block(s). It creates a means to perform functions. These computer program instructions can also be stored in computer readable or computer readable memory that can be oriented to a computer or other programmable data processing equipment to implement a function in a particular way, so that computer readable or computer readable memory It is also possible for the instructions stored in to produce an article of manufacture containing instructions means for performing the functions described in the flowchart block(s). Computer program instructions can also be mounted on a computer or other programmable data processing equipment, so a series of operational steps are performed on a computer or other programmable data processing equipment to create a process that is executed by the computer to generate a computer or other programmable data. It is also possible for instructions to perform processing equipment to provide steps for executing the functions described in the flowchart block(s).

Also, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing the specified logical function(s). It should also be noted that in some alternative implementations, it is also possible that the functions mentioned in the blocks occur out of sequence. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or it is also possible that the blocks are sometimes executed in reverse order according to a corresponding function.

At this time, the term'~ unit' used in this embodiment means software or hardware components such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), and'~ unit' performs certain roles. do. However,'~bu' is not limited to software or hardware. The'~ unit' may be configured to be in an addressable storage medium or may be configured to reproduce one or more processors. Thus, as an example,'~ unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, attributes, and procedures. , Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, database, data structures, tables, arrays, and variables. The functions provided within components and'~units' may be combined into a smaller number of components and'~units', or further separated into additional components and'~units'. In addition, the components and'~ unit' may be implemented to play one or more CPUs in the device or secure multimedia card. Also, in the embodiment,'~ unit' may include one or more processors.

Terms used to identify a connection node used in the following description, terms referring to network objects, terms referring to messages, terms referring to interfaces between network objects, terms referring to various identification information Etc. are exemplified for convenience of explanation. Therefore, the present disclosure is not limited to the terms described below, and other terms indicating objects having equivalent technical meanings may be used.

For convenience of description below, the present disclosure uses terms and names defined in 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) standard, or terms and names modified based on the terms. However, the present disclosure is not limited by the terms and names described above, and may be equally applied to systems conforming to other standards. In the present disclosure, the eNB may be used interchangeably with the gNB for convenience of explanation. That is, a base station described as an eNB may indicate gNB. In the present disclosure, the term terminal may refer to various wireless communication devices as well as mobile phones, NB-IoT devices, and sensors.

In a next-generation mobile communication system, since a base station can provide a service to a terminal based on a beam, and supports a number of functions, the size of an RRC message including setting information for many functions as well as beam-related setting information for setting it to the terminal. Can be very large. In addition, the next generation mobile communication system needs to support various data processing procedures because it needs to provide various services and service high data rates.

In the PDCP layer device, a maximum size that can be processed for data received from an upper layer is determined. For example, in a next-generation mobile communication system, a PDCP layer device can support up to 9 kilobytes in size for one data. Therefore, for example, if the size of user layer data received from a higher layer, such as an RRC message received from an RRC layer or a TCP/IP or UDP layer, is larger than the maximum size supported by the PDCP layer device (for example, 9 kilobytes), PDCP The layer device cannot process the data.

1A is a diagram showing the structure of an LTE system to which an embodiment is applied.

Referring to Figure 1a, the radio access network of the LTE system is the next generation base station (Evolved Node B, hereinafter ENB, Node B or base station) (1a-05, 1a-10, 1a-15, 1a-20), MME (1a- 25, Mobility Management Entity) and S-GW (1a-30, Serving-Gateway). User equipment (hereinafter referred to as UE or UE) 1a-35 may access an external network through ENBs 1a-05 to 1a-20 and S-GW 1a-30.

In FIG. 1A, ENBs 1a-05 to 1a-20 may correspond to Node B of a Universal Mobile Telecommunication System (UMTS) system. ENB is connected to the UE (1a-35) by a radio channel and performs a more complex role than Node B. In the LTE system, all user traffic, including real-time services such as Voice over IP (VoIP) through the Internet protocol, are serviced through a shared channel, so status information such as buffer status of UEs, available transmission power status, channel status, etc. It is necessary to have a device for scheduling by collecting, and the ENB (1a-05 ~ 1a-20) may be in charge. One ENB can usually control multiple cells. For example, in order to implement a transmission speed of 100 Mbps, the LTE system may use orthogonal frequency division multiplexing (OFDM) in a 20 MHz bandwidth, for example, as a radio access technology. In addition, an adaptive modulation & coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to a channel state of a terminal may be applied. S-GW (1a-30) is a device that provides a data bearer, and can create or remove a data bearer under the control of the MME (1a-25). The MME 1a-25 is a device in charge of various control functions as well as a mobility management function for a terminal, and may be connected to multiple base stations.

1B is a diagram illustrating a radio protocol structure in an LTE system to which an embodiment is applied.

Referring to Figure 1b, the radio protocol of the LTE system is the packet data convergence protocol (PDCP) (1b-05, 1b-40), radio link control (RLC) (1b-10, 1b-35) in the UE and the ENB, respectively. MAC (Medium Access Control) (1b-15, 1b-30). PDCP (Packet Data Convergence Protocol) (1b-05, 1b-40) is responsible for the operation of IP header compression/restore. The main functions of PDCP can be summarized as follows.

-Header compression and decompression (ROHC (RObust Header Compression) only)

-Transfer of user data

-In-sequence delivery of upper layer PDUs at PDCP re-establishment procedure for RLC AM (Acknowledged Mode)

-For split bearers in DC (only support for RLC AM): PDCP PDU routing for transmission and PDCP PDU reordering for reception)

-Duplicate detection of lower layer SDUs at PDCP re-establishment procedure for RLC AM

-Retransmission of PDCP SDUs at handover and, for split bearers in DC, of PDCP PDUs at PDCP data-recovery procedure, for RLC AM

-Encryption and decryption function (Ciphering and deciphering)

-Timer-based SDU discard function (Timer-based SDU discard in uplink.)

The radio link control (hereinafter referred to as RLC) (1b-10, 1b-35) may perform an automatic repeat request (ARQ) operation by reconfiguring the PDCP packet data unit (PDU) to an appropriate size. The main functions of RLC can be summarized as follows.

-Data transfer function (Transfer of upper layer PDUs)

-ARQ function (Error Correction through ARQ (only for AM data transfer))

-Concatenation, segmentation and reassembly of RLC SDUs (only for UM and AM data transfer)

-Re-segmentation of RLC data PDUs (only for AM data transfer)

-Reordering of RLC data PDUs (only for UM and AM data transfer)

-Duplicate detection (Duplicate detection (only for UM and AM data transfer))

-Error detection function (Protocol error detection (only for AM data transfer))

-RLC SDU deletion function (RLC SDU discard (only for UM and AM data transfer))

-RLC re-establishment

The MACs 1b-15 and 1b-30 are connected to various RLC layer devices configured in one terminal, multiplex the RLC PDUs to the MAC PDU, and demultiplex the RLC PDUs from the MAC PDU. The main functions of MAC can be summarized as follows.

-Mapping function (Mapping between logical channels and transport channels)

-Multiplexing and demultiplexing function (Multiplexing/demultiplexing of MAC SDUs belonging to one or different logical channels into/from transport blocks (TB) delivered to/from the physical layer on transport channels)

-Scheduling information reporting function

-HARQ function (Error correction through HARQ)

-Priority handling between logical channels (Priority handling between logical channels of one UE)

-Priority handling between UEs (Priority handling between UEs by means of dynamic scheduling)

-MBMS service identification function

-Transport format selection function

-Padding function

The physical (PHY) layer (1b-20, 1b-25) channel-codes and modulates the upper layer data, makes it an OFDM symbol and transmits it to a radio channel, or demodulates and decodes an OFDM symbol received through the radio channel and performs channel decoding. It is possible to perform an operation for transferring to a layer.

1C is a diagram showing the structure of a next-generation mobile communication system to which an embodiment is applied.

Referring to Figure 1c, the next generation mobile communication system (hereinafter referred to as NR or 5G) radio access network is a next-generation base station (New Radio Node B, NR gNB or NR base station) (1c-10) and NR CN (1c-05, New Radio Core Network). The user terminal (New Radio User Equipment, NR UE or terminal) 1c-15 may access an external network through the NR gNB 1c-10 and the NR CN 1c-05.

In Figure 1c, NR gNB (1c-10) corresponds to the evolved Node B (eNB) of the existing LTE system. NR gNB (1c-10) is connected to the NR UE (1c-15) in a wireless channel and can provide a service superior to Node B. In the next-generation mobile communication system, since all user traffic is serviced through a shared channel, a device is required to collect and schedule status information such as buffer status of UEs, available transmission power status, and channel status, and this is NR NB (1c-10) is in charge. One NR gNB 1c-10 usually controls multiple cells. In order to implement ultra-high-speed data transmission compared to the current LTE, it may have more than the existing maximum bandwidth, and orthogonal frequency division multiplexing (hereinafter referred to as OFDM) as a wireless access technology may additionally incorporate beamforming technology. . In addition, an adaptive modulation & coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to a channel state of a terminal may be applied. The NR CN 1c-05 may perform functions such as mobility support, bearer setup, and QoS (Quality of Service) setup. The NR CN (1c-05) is a device in charge of various control functions as well as mobility management functions for a terminal, and can be connected to multiple base stations. In addition, the next generation mobile communication system can be interlocked with the existing LTE system, and the NR CN (1c-05) can be connected to the MME (1c-25) through a network interface. MME (1c-25) may be connected to the existing base station eNB (1c-30).

1D is a diagram illustrating a radio protocol structure of a next-generation mobile communication system to which an embodiment is applied. .

Referring to Figure 1d, the radio protocol of the next-generation mobile communication system is NR Service Data Adaptation Protocol (SDAP) (1d-01, 1d-45), NR Packet Data Convergence Protocol (PDCP) (1d-05) at the terminal and the NR base station, respectively. , 1d-40), NR RLC (1d-10, 1d-35) and NR MAC (1d-15, 1d-30). The main functions of the NR SDAP (1d-01, 1d-45) may include some of the following functions.

-Transfer of user plane data

-Mapping function between QoS flow and data bearer for uplink and downlink (mapping between a QoS flow and a DRB for both DL and UL)

-Marking QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

-Reflective QoS flow to DRB mapping for the UL SDAP PDUs for uplink SDAP PDUs.

For the above-described SDAP layer device, the UE can set whether to use the header of the SDAP layer device or the function of the SDAP layer device, for each PDCP layer device, for each bearer, or for each logical channel, as an RRC message. When the header is set, the terminal is uplinked and downlinked by NAS non-access stratum quality of service (NAS QoS) setting 1-bit indicator (NAS reflective QoS) and AS QoS reflection setting 1-bit indicator (AS reflective QoS) in the SDAP header. It can instruct to update or reset the QoS flow and mapping information for the data bearer. The SDAP header described above may include QoS flow ID information indicating QoS. The above-described QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

The main functions of the NR PDCP (1d-05, 1d-40) may include some of the following functions.

-Header compression and decompression (ROHC only)

-Transfer of user data

-In-sequence delivery of upper layer PDUs

-Out-of-sequence delivery of upper layer PDUs

-Reordering function (PDCP PDU reordering for reception)

-Duplicate detection of lower layer SDUs

-Retransmission of PDCP SDUs

-Encryption and decryption function (Ciphering and deciphering)

-Timer-based SDU discard function (Timer-based SDU discard in uplink.)

Here, the order reordering function of the NR PDCP device includes a function of reordering PDCP PDUs received from a lower layer in order based on a PDCP sequence number (SN) and a function of delivering data to a higher layer in reordered order. can do. Or, the reordering function of the NR PDCP device (reordering) does not take the order into account, the function of immediately transmitting, reordering the function to record the lost PDCP PDUs, and reporting the status of the lost PDCP PDUs to the transmitting side And at least one of a function for requesting retransmission for lost PDCP PDUs.

The main functions of the NR RLC (1d-10, 1d-35) may include some of the following functions.

-Data transfer function (Transfer of upper layer PDUs)

-In-sequence delivery of upper layer PDUs

-Out-of-sequence delivery of upper layer PDUs

-ARQ function (Error Correction through ARQ)

-Concatenation, segmentation and reassembly of RLC SDUs

-Re-segmentation of RLC data PDUs

-Reordering of RLC data PDUs

-Duplicate detection function

-Protocol error detection

-RLC SDU deletion function (RLC SDU discard)

-RLC re-establishment

Here, the in-sequence delivery of the NR RLC device refers to a function of sequentially transmitting RLC SDUs received from a lower layer to an upper layer. In-sequence delivery of the NR RLC device is a function of reassembling and transmitting when one RLC SDU is originally divided into several RLC SDUs and receiving RLC PDUs through RLC sequence number ) Or PDCP reordering based on SN (sequence number), the ability to rearrange the order to record the lost RLC PDUs, the ability to report the status of the lost RLC PDUs to the sender, the lost RLC PDUs A function to request retransmission for a function, a function to deliver only RLC SDUs up to the previous layer in order, if there is a lost RLC SDU, or a timer if the specified timer expires even if there is a lost RLC SDU Includes the ability to deliver all RLC SDUs received before start to the upper layer in order, or to deliver all RLC SDUs received to the upper layer in order if the timer expires even if there is a missing RLC SDU. can do.

In addition, the out-of-sequence delivery function of the NR RLC device processes the RLC PDUs in the order in which they are received (regardless of the sequence number and sequence number order, in the order of arrival), and the sequence is sent to the PDCP device. It can be delivered regardless of (out-of-sequence delivery). In the case of segments, segments stored in a buffer or to be received at a later time can be received and reconstructed into a complete RLC PDU, processed, and then delivered to a PDCP device. The above-described NR RLC layer may not include a concatenation function, and may perform the above-described function in the NR MAC layer or replace it with a multiplexing function of the NR MAC layer.

The out-of-sequence delivery function of the NR RLC device may include a function of delivering RLC SDUs received from a lower layer directly to an upper layer regardless of order. The out-of-sequence delivery function of the RLC device is a function of reassembling and delivering when one RLC SDU is originally divided into several RLC SDUs, RLC SN of received RLC PDUs, or It may include at least one of a function of storing PDCP SNs and arranging the order to record lost RLC PDUs.

NR MAC (1d-15, 1d-30) may be connected to several NR RLC layer devices configured in one terminal, the main function of the NR MAC may include some of the following functions.

-Mapping function (Mapping between logical channels and transport channels)

-Multiplexing/demultiplexing of MAC SDUs

-Scheduling information reporting function

-HARQ function (Error correction through HARQ)

-Priority handling between logical channels (Priority handling between logical channels of one UE)

-Priority handling between UEs (Priority handling between UEs by means of dynamic scheduling)

-MBMS service identification function

-Transport format selection function

-Padding function

The NR PHY layer (1d-20, 1d-25) channel-codes and modulates upper layer data, makes it an OFDM symbol and transmits it to a radio channel, or demodulates and decodes an OFDM symbol received through a radio channel to a higher layer. You can perform the transfer operation.

1E is a diagram illustrating a procedure for establishing a connection between a terminal and a network according to an embodiment.

Referring to FIG. 1E, the base station (gNB) sends an RRCConnectionRelease message to the terminal (UE) when the terminal (UE) transmitting and receiving data in the RRC connection mode has no transmission or reception of data for a predetermined reason or for a predetermined time. It can be switched to the RRC idle mode or the RRC inactive mode (1e-01). Subsequently, a terminal that is not currently connected (hereinafter referred to as an idle mode UE) may perform an RRC connection establishment process or an RRC connection resume procedure with a base station (gNB) when data to be transmitted occurs.

The terminal (UE) establishes reverse transmission synchronization with the base station (gNB) through a random access process and transmits an RRCConnectionRequest message to the base station (gNB) (1e-05). The RRCConnectionRequest message may include an identifier of a terminal (UE) and a reason for establishing a connection (establishmentCause).

The base station (gNB) transmits an RRCConnectionSetup message to the UE to establish an RRC connection (1e-10). The RRCConnectionSetup message may include at least one of configuration information for each logical channel, configuration information for each bearer, configuration information for a PDCP layer device, configuration information for an RLC layer device, and configuration information for a MAC layer device.

The base station (gNB) allocates a bearer identifier (eg, SRB identifier or DRB identifier) for each bearer through the RRCConnectionSetup message, and sets the PDCP layer device, RLC layer device, MAC layer device, and PHY layer device for each bearer. And may indicate mapping of the logical channel identifier. In addition, the base station (gNB) can set the length (for example, 12 bits or 18 bits) of the PDCP serial number used by the PDCP layer device for each bearer through the RRCConnectionSetup message, and the RLC serial number used by the RLC layer device. You can set the length of (for example, 6 bits or 12 bits or 18 bits).

In addition, the base station (gNB) is a PDCP layer device or SDAP layer device or RRC layer device or a new method for partitioning and reassembling the RRC message or data described in the present disclosure for each bearer (SRB or DRB) through the RRCConnectionSetup message. It may indicate whether or not to use the layer device. In addition, when the RRC message or data division method and re-assembly method are used in the new layer device, it may indicate whether to use the header of the new layer device. For example, when it is set to use the RRC message or data partitioning method and reassembly method described in the present disclosure, a header of a new layer device may be used, and the RRC message or data partitioning method and data described in the present disclosure may be used. If the assembly method is not used, the header of the new layer device may not be used.

The UE establishing the RRC connection transmits an RRCConnetionSetupComplete message to the base station (gNB) (1e-15). The RRCConnetionSetupComplete message may include a control message called SERVICE REQUEST in which the UE requests the AMF or MME for bearer setup for a given service. The base station (gNB) transmits the SERVICE REQUEST message stored in the RRCConnetionSetupComplete message to the AMF or MME (1e-20). The AMF or MME can determine whether to provide the service requested by the UE.

As a result of the determination, if the UE decides to provide the requested service, the AMF or MME sends a message called INITIAL CONTEXT SETUP REQUEST to the base station (gNB) (1e-25). The INITIAL CONTEXT SETUP REQUEST message may include QoS (Quality of Service) information to be applied when setting a Data Radio Bearer (DRB), and security-related information (eg, Security Key, Security Algorithm) to be applied to the DRB. .

The base station (gNB) exchanges the SecurityModeCommand message (1e-30) and the SecurityModeComplete message (1e-35) to establish security with the terminal (UE). When the security setting is completed, the base station (gNB) transmits an RRCConnectionReconfiguration message to the UE (1e-40).

The base station (gNB) allocates a bearer identifier (eg, SRB identifier or DRB identifier) for each bearer through an RRCConnectionReconfiguration message, and sets a PDCP layer device, RLC layer device, MAC layer device, and PHY layer device for each bearer. Can indicate, and may indicate the mapping of the logical channel identifier. In addition, the base station (gNB) can set the length (for example, 12 bits or 18 bits) of the PDCP serial number used in the PDCP layer device for each bearer through the RRCConnectionSetup message, and the RLC serial number used in the RLC layer device. The length (for example, 6 bits or 12 bits or 18 bits) can be set.

In addition, the base station (gNB) in the RRCConnectionReconfiguration message for each bearer (SRB or DRB) RRC message described in the present disclosure or a method of re-assembly of the data and PDCP layer device or SDAP layer device or RRC layer device or new layer It can indicate whether or not to use the device. In addition, when the RRC message or data division method and reassembly method are used in the new layer device, it may indicate whether to use the header of the new layer device. For example, when it is set to use the RRC message or data partitioning method and reassembly method described in the present disclosure, a header of a new layer device may be used, and the RRC message or data partitioning method and data described in the present disclosure may be used. If the assembly method is not used, the header of the new layer device may not be used.

In addition, the RRCConnectionReconfiguration message may include configuration information of the DRB to which user data is to be processed, and the UE configures the DRB by applying the information and transmits the RRCConnectionReconfigurationComplete message to the base station (gNB) (1e-45). The terminal (UE) and the base station (gNB) that has completed the DRB setup may send an INITIAL CONTEXT SETUP COMPLETE message to the AMF or MME and complete the connection (1e-50).

When all of these processes are completed, the UE transmits and receives data through the base station (gNB) and the core network (1e-55, 1e-60). According to an embodiment, the data transmission process may be largely composed of three steps: RRC connection setup, security setup, and DRB setup. In addition, the base station (gNB) may transmit an RRC Connection Reconfiguration message to make a new setting to the UE for a predetermined reason, or to add or change the setting (1e-65).

The base station (gNB) allocates a bearer identifier (eg, SRB identifier or DRB identifier) for each bearer through an RRCConnectionReconfiguration message, and sets a PDCP layer device, RLC layer device, MAC layer device, and PHY layer device for each bearer. Can indicate and may indicate the mapping of the logical channel identifier. In addition, the base station (gNB) can set the length (for example, 12 bits or 18 bits) of the PDCP serial number used by the PDCP layer device for each bearer through the RRCConnectionSetup message, and the RLC serial number used by the RLC layer device. You can set the length of (for example, 6 bits or 12 bits or 18 bits).

In addition, whether or not to divide and reassemble the RRC message or data described in the present disclosure for each bearer (SRB or DRB) in the RRCConnectionReconfiguration message from the PDCP layer device or the SDAP layer device or the RRC layer device or the new layer device. I can order. In addition, when the RRC message or data division method and reassembly method are used in the new layer device, it may indicate whether to use the header of the new layer device. For example, when it is set to use the RRC message or data partitioning method and reassembly method described in the present disclosure, a header of a new layer device may be used, and the RRC message or data partitioning method and data described in the present disclosure may be used. If the assembly method is not used, the header of the new layer device may not be used.

The procedure for establishing a connection between a UE (UE) and a base station (gNB) described in the present disclosure may be applied to establishing a connection between a UE (UE) and an LTE base station (gNB), and a UE (UE) and an NR base station (gNB). It can be applied to the connection setting of.

In the present disclosure, the bearer may include a signaling radio bearer (SRB) and a data radio bearer (DRB). The SRB is mainly used to transmit and receive RRC messages of the RRC layer device, and the DRB is mainly used to transmit and receive user layer data. In addition, the UM DRB means a DRB using an RLC layer device operating in the Unacknowledged Mode (UM) mode, and the AM DRB means a DRB using an RLC layer device operating in the AM (Acknowledged Mode) mode.

The data division method and re-assembly method of upper layer data (RRC message or user layer data) described in the present disclosure define a new indicator (for example, a 1-bit or 2-bit indicator or serial number), and based on this indicator It characterized in that the data is divided and reassembled in the RRC layer device or PDCP layer device or SDAP layer device or newly defined layer device, and the data is divided and re-established for the data of the PDCP layer device or the layer device thereon. It is characterized by assembling. In addition, when the data division method and the reassembly method described in the present disclosure are used in a new layer device, it is characterized in that a new indicator is defined and applied to a new header. The data division method and re-assembly method of upper layer data described in the present disclosure may or may not be set for each bearer.

In the present disclosure, the terminal or the base station may or may not use a data division method and a reassembly method of higher layer data described in this disclosure for each bearer. For example, when a data splitting method and a reassembly method of higher layer data described in the present disclosure are set in a specific bearer, data of the upper layer data described in the present disclosure is divided into RRC messages or data transmitted and received in the specific bearer. The method and the reassembly method can always be applied, and when applied in a new layer device, a new header including segmentation information can always be used. In addition, the data segmentation method and reassembly method of the upper layer data described in this disclosure may not always be applied to a bearer in which the data segmentation method and reassembly method of the higher layer data described in the present disclosure are not set. When applied in a layer device, a new header including segmentation information may not always be used.

As another method, a routing method based on the size of the RRC message or user layer data may be used. In the present disclosure, when the terminal or the base station attempts to transmit the RRC message or user layer data, if the size of the RRC message or user layer data to be transmitted exceeds a predetermined threshold (for example, 9 kb), a higher level described in the present disclosure It can be divided through a bearer (for example, new SRB4 or SRB5 or DRB2) to which the data division method and reassembly method of the layer data are applied, and the RRC message or user layer data can be divided and transmitted. That is, in the bearer in which the data division method of the upper layer data described in the present disclosure is set for the RRC message or user layer data, the division method is applied to the RRC message or user layer data, and the RRC message or user layer data is transmitted by division. Can. If the size of the RRC message or user layer data to be transmitted does not exceed a predetermined threshold (for example, 9 kb) when the terminal or the base station attempts to transmit the RRC message or user layer data, the higher level described in the present disclosure An RRC message or user layer data may be transmitted through a bearer (eg, SRB0 or SRB1 or SRB2 or DRB1) to which the data division method and the reassembly method of the layer data are not applied.

Alternatively, by defining and setting a separate bearer (SRB or DRB) supporting data processing of a data size larger than the size of the data supported by the PDCP layer device (for example, 9 kb), the PDCP layer device An RRC message or data larger than the size of the supported data may perform data processing through the separate bearer described above and enable data transmission and reception.

In one embodiment, the base station may request whether the terminal supports capability information and receives a terminal capability report message to determine whether the terminal supports a data division method and a reassembly method of higher layer data described in the present disclosure.

1F is a diagram illustrating a procedure for a base station to check a terminal's capability according to an embodiment.

Referring to FIG. 1F, a base station (gNB) may transmit a UECapabilityEnqiry message to a terminal (UE) to check the capability of the terminal (UE) so that the terminal (UE) reports the capability of the terminal (UE). When the UECapabilityEnqiry message is received as an RRC message, the UE can report the UE capability by configuring the UE capabilities in the UECapabilityInformation message and sending it to the base station (gNB) to report the UE capability.

When the UE transmits the UECapabilityInformation message, the UE may include an indicator that supports a data division method and a reassembly method of higher layer data described in the present disclosure.

As described above, although the UE and the network have established a data partitioning method and a reassembly method of higher layer data described in the present disclosure for a specific bearer through an RRC connection establishment or resumption procedure, if there is an obstacle between the UE and the network Alternatively, when signal loss or radio link failure (RLF) occurs due to radio interference or rapid mobility of the UE, the UE and the base station (gNB) re-establish the RRC connection procedure to establish a connection (RRC Connection Re -establishment). At this time, it is possible to deactivate or stop or release or fall back or not to use the data division method and the re-assembly method of upper layer data for a specific bearer. That is, when the UE performs the RRC connection re-establishment procedure, the data division method and re-assembly method of upper layer data may not be applied. For example, the data division method and reassembly method of the higher layer data described in the present disclosure will not be applied until the base station (gNB) resets the data division method and reassembly method of higher layer data for a specific bearer. (For example, when a data division method and a reassembly method of higher layer data are applied in a new layer device, a new header may not be used). In addition, when the base station (gNB) re-establishes a method for re-establishing data and re-assembling data of higher-layer data using an RRC connection re-establishment procedure or an RRC message, a data partitioning method and re-assembly method of higher-layer data described in the present disclosure. Can be applied again (for example, when a data division method and a reassembly method of higher layer data are applied in a new layer device, a new header may be used again).

In another method, the base station (gNB) and the UE (UE) are described in the present disclosure about the RRC re-establishment procedure for convenience of implementation for a bearer in which a data division method and a re-assembly method of the upper layer data are set once. The method of dividing and reassembling data of hierarchical data may be continuously applied.

When the data division method and re-assembly method of the upper layer data described in the present disclosure are applied in a new layer device, when the UE transitions to the RRC inactive mode or the RRC idle mode, it is stored in a buffer corresponding to the new layer device. The re-assembled and segmented data (segments) that have not been re-assembled are all discarded by the transmitting new layer device or the receiving new layer device to prevent reassembly errors or unnecessary transmission errors that may occur when reestablishing the network and connection. Can.

In addition, when transitioning to the RRC deactivation mode, the data division method and reassembly method of the upper layer data described in the present disclosure may be suspended, and may be resumed by an instruction of the network when resetting the RRC connection. have. In addition, when transitioning to the RRC idle mode, the data division method and reassembly method of the upper layer data described in the present disclosure may be released. The new layer device data discard procedure may be defined as a new layer device re-establishment procedure, and when the PDCP layer device performs re-establishment, an indicator may be transmitted to the new layer device to trigger the discard procedure.

Hereinafter, specific embodiments of a data division method and a reassembly method of upper layer data described in the present disclosure will be described.

1G is a diagram illustrating a first embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.

A first embodiment of a data division method and a reassembly method of upper layer data described in the present disclosure defines a new layer device (SEG layer), and defines fields for division and reassembly in a new header in the new layer device. It is characterized in that it is used for splitting at the transmitting end and used for reassembly at the receiving end.

In the first embodiment of the data division method and reassembly method of upper layer data, the new layer device is between the PDCP layer device (1g-15) and the RRC layer device (1g-05) for SRBs that transmit and receive RRC messages. It can be located and receives data from the upper layer device, the RRC layer device, and if the received data is larger than the maximum size or a specific threshold supported by the PDCP layer device, a new header is configured and includes the segmentation information. Data can be divided and attached with a new header to be delivered to the lower PDCP layer device. If the received data is smaller than the maximum size or a specific threshold supported by the PDCP layer device, a new header may be configured, and an indication that the data is not split may be included in the segmentation information and attached to the data to be transmitted to the lower PDCP layer device. . This new header can always be present. However, to reduce overhead, a 1-bit indicator may be defined at the beginning to indicate whether a new header exists. For example, a new header or 1 bit of the header of the PDCP layer device may be defined to indicate whether a new header exists or whether data is divided. At the receiving end, the new layer device receives data from the lower PDCP layer device, reads the new header, checks the segmentation information, performs reassembly if it is segmented, removes the header if it is not segmented, and delivers an RRC message to the upper layer. .

In the first embodiment of the data division method and reassembly method of upper layer data, the new layer device is between the PDCP layer device (1g-50) and the SDAP layer device (1g-60) for DRBs that transmit and receive user layer data. It can be located at and receives data from a higher layer device, SDAP layer device or higher layer device (if SDAP layer device is not set), and the received data is greater than the maximum size or a specific threshold supported by the PDCP layer device. In a large case, a new header may be configured, the corresponding data may be divided, including segmentation information, and a new header may be attached and transmitted to a lower PDCP layer device. If the received data is smaller than the maximum size or a specific threshold value supported by the PDCP layer device, a new header is configured, and the indication that the segment is not included is included in the segmentation information, attached to the received data, and transmitted to the lower PDCP layer device. Can. This new header can always be present. However, in order to reduce overhead, a 1-bit indicator may be defined at the beginning to indicate whether a new header exists. For example, a new header or 1 bit of the header of the PDCP layer device may be defined to indicate whether a new header exists or whether data is divided. When receiving data from the lower PDCP layer device, the new layer device at the receiving end reads the new header, checks the segmentation information, performs reassembly if it is segmented, removes the header if it is not segmented, and transfers the data to the upper layer.

1H is a diagram illustrating a specific partitioning and reassembly method for a first embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.

1H to 1H-01 show a 1-1 embodiment of a data division method and a reassembly method of upper layer data.

In the first-first embodiment, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field indicates complete data, first segment, middle segment (or segment other than the first and last segment), and last segment, respectively, for the four cases of 00, 01, 11, and 10. Can be defined as There are 24 kinds of one-to-one mapping for 00, 01, 11, 10 of S field, complete data that is not split, first segment, middle segment (or segment other than first and last segment), and last segment. It can be, and one of them can define the mapping relationship. For example, the S field can be defined as shown in [Table 1] below.

[Table 1]

As illustrated in FIG. 1G, since the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, when the receiving RLC layer device is operated in the AM mode, data transmission without loss is transmitted. It supports and sorts data in order by PDCP serial number from the receiving PDCP layer device and delivers it to the receiving SEG layer device. Therefore, in the new layer device, a serial number may not be required, and if the 2-bit S field is used, the RRC message or data may be divided by the transmitting end, and the divided data may be successfully reassembled and received at the receiving end.

The operation of the transmitting end for the first-first embodiment of the data division method and the re-assembly method of upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

If data segmentation is performed, in the case of the first segmentation data (segment), the S field of the new header is set to 01, the header is attached in front of the first segmentation data (segment), and transmitted to the lower layer device. In the case of the intermediate segmentation data (segment), the S field of the new header is set to 11, the header is attached in front of the intermediate segmentation data (segment), and transmitted to the lower layer device. In the case of the last segmentation data (segment), the S field of the new header is set to 10, and a header is attached before the last segmentation data and transmitted to the lower layer device.

If data division is not performed, the S field of the new header is set to 00 for data received from the upper layer, the header is attached in front of the data, and the data is transmitted to the lower layer device.

The operation of the receiving end for the first-first embodiment of the data division method and the re-assembly method of upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data (segment), the new layer device of the receiving end checks the S field of the new header and stores it in the buffer, and reassembles when the first segment, the middle segment, and the last segment are all received. The new headers of corresponding segments may be removed and a complete RRC message or data may be constructed and delivered to a higher layer device. Here, the reassembly procedure may be performed when the S field of the new header indicates the last segment. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1H to 1H-11 show a first-2 embodiment of a data division method and a reassembly method of upper layer data.

In the embodiment 1-2, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field indicates complete data that is not divided for three of the four cases of 00, 01, 11, and 10, the segment that is not the last segment (or indicates that there is another segment), and the last segment, respectively. It can be defined to indicate. The number of 3 cases among 00, 01, 11, and 10 of the S field, complete data that has not been split, segments other than the last segment (or indicating that there is another segment), and one-to-one mapping to the last segment are of 24 types. There may be, and one of them may define a mapping relationship. In addition, the number of remaining cases among 00, 01, 11, and 10 can be set as a reservation value, and reserved for other functions later. For example, the S field can be defined as shown in [Table 2] below.

[Table 2]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. Therefore, in the new layer device, a serial number may not be necessary, and if the 2-bit S field is used, the RRC message or data may be divided by the transmitting end, and the divided data may be successfully reassembled and received at the receiving end.

The operation of the transmitting end in the first-2 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

If data segmentation is performed, if it is not the last segmentation data (segment), the S field of the new header is set to 01, a header is attached in front of the segmentation data, and it is transmitted to a lower layer device. In the case of the last segmentation data (segment), the S field of the new header is set to 10, the header is attached before the last segmentation data, and it is transmitted to the lower layer device.

If data division is not performed, the S field of the new header is set to 00 for data received from the upper layer, the header is attached in front of the data, and the data is transmitted to the lower layer device.

The operation of the receiving end for the first-2 embodiments of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data, the new layer device of the receiving end checks the S field of the new header and stores it in a buffer, and when both the last segment and the last segment are received, reassembly is performed, and the new header of the segments You can remove them and compose a complete RRC message or data and deliver it to a higher layer device. Here, the reassembly procedure may be performed when the S field of the new header indicates the last segment. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1H to 1H-21 illustrate a first-3 embodiment of a data division method and a reassembly method of upper layer data.

In the embodiment 1-3, a 1-bit segmentation field may be defined and used by the transmitting end and the receiving end. The S field may be defined to indicate the complete data (or the last segment) that is not divided, and the segment other than the last segment (or indicating that there is another segment) for the number of two cases of 0 and 1, respectively. There are two types of one-to-one mapping of the number of 2 cases in S field 0 and 1, complete data that is not divided (or the last segment), and a segment other than the last segment (or indicating that there is another segment). You can define a mapping relationship with one of them. For example, the S field can be defined as shown in [Table 3] below.

[Table 3]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. Therefore, in a new layer device, a serial number may not be necessary, and if the 1-bit S field is used, the RRC message or data is divided by the transmitting end, and the divided data can be successfully reassembled and received at the receiving end.

The operation of the transmitting end for the first to third embodiments of the data division method and the reassembly method of upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

If data segmentation is performed, if it is not the last segmentation data (segment), the S field of the new header is set to 1, a header is attached in front of the segmentation data, and it is transmitted to a lower layer device. And for the last segmented data (segment) (or for unpartitioned complete data), set the S field of the new header to 0, attach the header before the last segmented data (or complete segmented data), and lower layer To the device.

If data division is not performed, the S field of the new header is set to 0 for data received from the upper layer, the header is attached in front of the data, and the data is transmitted to the lower layer device.

The operation of the receiving end for the 1-3 embodiments of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the information indicated by the header A check is performed to indicate that there is no last segmented data (segment) or complete data that has not been segmented or another segment, or that there is segmented data (segment) or another segment.

If the S field of the new header of the currently received data indicates 0 (that is, the last segmented data (segment) or the complete undivided data or no other segment), the header of the previously received data If among the data received after the last data in which the S field is indicated as 0, there are data in which the S field of the header is set to 1, the data set in the S field of the header are reassembled in the order in which they were received along with the currently received data. It can compose complete data, remove new headers and pass it to higher layer devices.

If the S field of the new header of the currently received data indicates 0, among the previously received data, the S field of the header is set to 1 among the data received after the last data indicated by the S field as 0. If there is no data, i.e., if the S field of the header of the previously received data was set to 0, the new received header is removed because the current received data is complete data that has not been split, and the complete data is sent to the upper layer device. Can pass.

If the S field of the new header of the currently received data indicates 1 (if there is a segmented data (segment) or another segment), check the new header of the data and remove it until reassembly is performed. Alternatively, it is stored in the buffer until the data with the S field of the header set to 0 arrives. Here, the received segments are reassembled and composed of complete data, and then transmitted to a higher layer device, and thus discarded from the buffer.

1I is a diagram illustrating a specific partitioning and reassembly method for a second embodiment of a data division method and a reassembly method of upper layer data according to an embodiment.

1i to 1i-01 show a 2-1 embodiment of a data division method and a reassembly method of upper layer data.

In the 2-1 embodiment, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field indicates the complete data, the first segment, the middle segment (or the segment other than the first and last segment), and the last segment, respectively, for the four cases of 00, 01, 11, and 10. Can be defined as There are 24 kinds of one-to-one mapping for 00, 01, 11, 10 of S field, complete data that is not divided, first segment, middle segment (or segment other than the first and last segment), and last segment. It can be, and one of them can define the mapping relationship. For example, the S field can be defined as shown in [Table 4] below.

[Table 4]

As described in FIG. 1G, since the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, when the receiving RLC layer device operates in the AM mode, it supports lossless data transmission. Then, the received PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. If this occurs, the new layer device needs the serial number, and even if the loss occurs only when the serial number is used with the 2-bit S field, the RRC message or data is split at the transmitting end, and the partitioned data is successfully received at the receiving end. It can be reassembled and received.

The operation of the transmitting end in the 2-1 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the 2-1 embodiment, when the serial number is assigned, the same serial number may be assigned to the divided data (segments) that are divided for the same upper layer data (SEG SDU). Therefore, it is possible to indicate that segments having the same serial number have been divided for the same data. However, if 4 or more segments are divided for one and the same data, and if the 2nd or 3rd segment is lost, because the 2nd or 3rd segment lost at the receiving end cannot be distinguished or the loss cannot be detected. Reassembly errors may occur. That is, reassembly may not be performed successfully. Therefore, if the segment is limited to 3 or less, it can operate normally without errors.

The new layer device of the transmitting end assigns the same serial number to the segments if data division is performed, sets the S field of the new header to 01 for the first division data (segment), and the first division data (segment). Attach a header in front of it and forward it to the lower layer device. In the case of the intermediate segmentation data (segment), the S field of the new header is set to 11, the header is attached in front of the intermediate segmentation data (segment), and transmitted to the lower layer device. In the case of the last segmentation data (segment), the S field of the new header is set to 10, and a header is attached before the last segmentation data and transmitted to the lower layer device.

If data division is not performed, the S field of the new header is set to 00 for data received from the upper layer, a serial number is assigned, and a header is attached in front of the data and transmitted to a lower layer device.

The operation of the receiving end for the 2-1 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split. In addition, it can be confirmed that segments having the same serial number are divided from one data.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data (segment), the new layer device of the receiving end checks the serial number and S field of the new header and stores it in the buffer, and reassembles when all the first segment, middle segment, and last segment are received. Perform, remove the new headers of the segments and compose a complete RRC message or data and deliver it to the higher layer device. Here, the reassembly procedure may be performed when all segments are received for a specific serial number. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1i to 1i-02 show a 2-2 embodiment of a data division method and a reassembly method of upper layer data.

In the embodiment 2-2, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field indicates complete data, first segment, middle segment (or segment other than the first and last segment), and last segment, respectively, for the four cases of 00, 01, 11, and 10. Can be defined as There are 24 kinds of one-to-one mapping for 00, 01, 11, 10 of S field, complete data that is not split, first segment, middle segment (or segment other than first and last segment), and last segment. It can be, and one of them can define the mapping relationship. For example, the S field can be defined as shown in [Table 5] below.

[Table 5]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. If this occurs, the new layer device needs the serial number, and even if the loss occurs only when the serial number is used with the 2-bit S field, the RRC message or data is split at the transmitting end, and the partitioned data is successfully received at the receiving end. It can be reassembled and received.

The operation of the transmitting end in the 2-2 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the second-2 embodiment, when serial numbers are allocated, different serial numbers may be assigned to divided data (segments) that are divided for the same upper layer data (SEG SDU). Accordingly, the serial number indicates the order of each segment, and the S field can indicate from which part of the data the segments are divided. Therefore, even if 4 or more segments are divided for one and the same data, and the 2nd or 3rd segment is lost, the 2nd or 3rd segment lost at the receiving end can be distinguished using a serial number and detects whether or not it is lost. Can.

The new layer device of the transmitting end assigns different serial numbers to segments if data division is performed, sets the S field of the new header to 01 for the first division data (segment), and the first division data (segment). ) In front of the header and forward it to the lower layer device. In the case of the intermediate segmentation data (segment), the S field of the new header is set to 11, the header is attached in front of the intermediate segmentation data (segment), and transmitted to the lower layer device. In the case of the last segmentation data (segment), the S field of the new header is set to 10, the header is attached to the front of the last segmentation data, and it is transmitted to the lower layer device.

If data division is not performed, the S field of the new header is set to 00 for data received from the upper layer, a serial number is assigned, and a header is attached in front of the data and transmitted to a lower layer device.

The operation of the receiving end for the second-2 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split. And it can be seen that the serial number indicates the order of different segments. Therefore, when a gap of the serial number occurs, it can be seen that a loss occurred.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data (segment), the new layer device of the receiving end checks the serial number and S field of the new header and stores it in the buffer, and reassembles when all the first segment, middle segment, and last segment are received. Perform, remove the new headers of the segments and compose a complete RRC message or data and deliver it to the higher layer device. Here, the reassembly procedure may be performed when all segments are received for one data (SEG SDU) by checking the serial number and the S field. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1i to 1i-11 show second to third embodiments of a data division method and a reassembly method of upper layer data.

In the second-3 embodiment, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field is the complete data that is not segmented, the segment other than the last segment (or indicating that there is another segment), and the last segment, respectively, for three of the four cases of 00, 01, 11, and 10 It can be defined to indicate. The number of 3 cases among 00, 01, 11, and 10 of the S field, complete data that has not been split, segments other than the last segment (or indicating that there is another segment), and one-to-one mapping to the last segment are of 24 types. There may be, and one of them may define a mapping relationship. And the number of remaining cases among 00, 01, 11, and 10 can be reserved for other functions later as a reservation value. For example, the S field can be defined as shown in [Table 6] below.

[Table 6]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. If this occurs, the new layer device needs the serial number, and even if the loss occurs only when the serial number is used with the 2-bit S field, the RRC message or data is split at the transmitting end, and the partitioned data is successfully received at the receiving end. It can be reassembled and received.

The operation of the transmitting end for the second to third embodiments of the data division method and the reassembly method of upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the second-3 embodiment, when the serial number is allocated, the same serial number may be allocated to the divided data (segments) that have been divided for the same upper layer data (SEG SDU). Therefore, it is possible to indicate that segments having the same serial number have been divided for the same data. However, if 4 or more segments are divided for one and the same data, and if the 2nd or 3rd segment is lost, because the 2nd or 3rd segment lost at the receiving end cannot be distinguished or the loss cannot be detected. Reassembly errors may occur. That is, reassembly may not be performed successfully. Therefore, if the number of segments is limited to 3 or less, it can operate normally without errors.

The new layer device of the transmitting end assigns the same serial number to the segments if data segmentation is performed, and if it is not the last segmentation data (segment), sets the S field of the new header to 01, and attaches the header in front of the segmentation data And forward it to the lower layer device. In the case of the last segmentation data (segment), the S field of the new header is set to 10, the header is attached before the last segmentation data, and it is transmitted to the lower layer device.

If data division is not performed, a serial number is assigned, and the S field of a new header is set to 00 for data received from a higher layer, a header is attached in front of the data, and the data is transmitted to a lower layer device.

The operation of the receiving end for the second to third embodiments of the data division method and the reassembly method of upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split. In addition, it can be confirmed that segments having the same serial number are divided from one data.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data, the new layer device of the receiving end checks the serial number and S field of the new header and stores it in the buffer, and re-assembles the segment and the last segment when both segments are received. Remove the new headers and compose a complete RRC message or data and deliver it to the upper layer device. Here, the reassembly procedure may be performed when all segments are received for a specific serial number. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1i to 1i-12 show a 2-4 embodiment of a data division method and a reassembly method of upper layer data.

In the 2-4 embodiment, a 2-bit S field (segmentation field) may be defined and used by the transmitting end and the receiving end. The S field indicates complete data that is not divided for three of the four cases of 00, 01, 11, and 10, the segment that is not the last segment (or indicates that there is another segment), and the last segment, respectively. It can be defined to indicate. The number of 3 cases among 00, 01, 11, and 10 of the S field, complete data that has not been split, segments other than the last segment (or indicating that there is another segment), and one-to-one mapping to the last segment are of 24 types. There may be, and one of them may define a mapping relationship. And the number of remaining cases among 00, 01, 11, and 10 can be reserved for other functions later as a reservation value. For example, the S field can be defined as shown in [Table 7] below.

[Table 7]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. When this occurs, the new layer device needs the serial number, and the serial number must be used together with the 2-bit S field to split the RRC message or data at the transmitting end even when the loss occurs, and to successfully split the data at the receiving end. It can be reassembled and received.

The operation of the transmitting end in the 2-4 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the 2-4th embodiment, when serial numbers are assigned, different serial numbers may be assigned to divided data (segments) that have been divided for the same upper layer data (SEG SDU). Accordingly, the serial number indicates the order of each segment, and the S field can indicate from which part of the data the segments are divided. Therefore, even if 4 or more segments are divided for one and the same data, and the 2nd or 3rd segment is lost, the 2nd or 3rd segment lost at the receiving end can be distinguished using a serial number, and detection of loss is detected. Can.

The new layer device of the transmitting end assigns different serial numbers to segments if data division is performed, sets the S field of the new header to 01 if it is not the last division data (segment), and sets the header before the division data. Attach and forward to lower layer devices. In the case of the last segmentation data (segment), the S field of the new header is set to 10, the header is attached before the last segmentation data, and it is transmitted to the lower layer device.

If data division is not performed, a serial number is assigned, and the S field of a new header is set to 00 for data received from a higher layer, a header is attached in front of the data, and the data is transmitted to a lower layer device.

The operation of the receiving end for the 2-4 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the received data is divided. Check whether it is RRC message or data or RRC message or data that is not split. And it can be seen that the serial number indicates the order of different segments. Therefore, when a gap of the serial number occurs, it can be seen that a loss occurred.

The new layer device of the receiving end checks the new header of the currently received data, and if the RRC message or data is not split, removes the new header and delivers the RRC message or data to the upper layer device. If it is a segmented RRC message or data, the new layer device of the receiving end checks the serial number and S field of the new header and stores it in the buffer, and re-assembles the segment and the last segment when both segments are received. Remove the new headers and compose a complete RRC message or data and deliver it to the upper layer device. Here, the reassembly procedure may be performed when all segments are received for one data (SEG SDU) by checking the serial number and the S field. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1i to 1i-21 show a 2-5 embodiment of a data division method and a reassembly method of upper layer data.

In the 2-5th embodiment, a 1-bit Segmentation field may be defined and used by the transmitting end and the receiving end. The S field may be defined to indicate the complete data (or the last segment) that is not divided, and the segment other than the last segment (or indicating that there is another segment) for the number of two cases of 0 and 1, respectively. There are two types of one-to-one mapping of the number of 2 cases in S field 0 and 1, complete data that is not divided (or the last segment), and a segment other than the last segment (or indicating that there is another segment). Can be defined as one of them. For example, the S field can be defined as shown in [Table 8] below.

[Table 8]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. If this occurs, the new layer device needs the serial number, and even if the loss occurs only when the serial number is used with the 2-bit S field, the RRC message or data is split at the transmitting end, and the partitioned data is successfully received at the receiving end. It can be reassembled and received.

The operation of the transmitting end in the second to fifth embodiments of the data division method and the reassembly method of upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the 2-5 embodiment, when the serial number is allocated, the same serial number may be allocated to the divided data (segments) that are divided for the same upper layer data (SEG SDU). Therefore, it is possible to indicate that segments having the same serial number have been divided for the same data. However, if 3 or more segments are divided for one and the same data, and if the 1st or 2nd segment is lost, it is impossible to distinguish the 1st or 2nd segment lost at the receiving end, or because it is impossible to detect the loss. Reassembly errors may occur. That is, reassembly may not be performed successfully. Therefore, if the segment is limited to 2 or less, it can operate normally without errors. However, since the S field has only one bit indicator, if the last segment is lost, it may have a problem that re-assembly cannot be performed on the data after which the last segment is lost and the next data. Therefore, the 1-bit indicator is a useful method when there is no loss that the RLC layer device operates in the RLC AM mode.

The new layer device of the transmitting end assigns the same serial number to segments if data division is performed, sets the S field of the new header to 1 if it is not the last division data (segment), and attaches a header in front of the division data And forward it to the lower layer device. Then, in the case of the last segmented data (segment) (or in the case of complete data that has not been segmented), the S field of the new header is set to 0, the header is attached before the last segmented data (or complete data that has not been segmented), and the sub Layer device.

If data division is not performed, a serial number is assigned, and the S field of the new header is set to 0 for data received from the upper layer, a header is attached in front of the data, and the data is transmitted to a lower layer device.

The operation of the receiving end for the 2-5 embodiment of the data division method and the reassembly method of the upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the information indicated by the header Check to see if there is no last segmented data (segment) or complete segmented data or another segment, or if there is segmented data (segment) or another segment. And it can be confirmed that the segments with the same serial number are divided in one data.

The new layer device of the receiving end indicates that the S field of the new header of the currently received data indicates 0 (that is, the last segmented data (segment) or complete data not segmented or no other segment) and the currently received series. If the data with the same serial number as the number and the S field of the header is indicated as 1 is received, the data are reassembled in the order received with the currently received data to construct complete data, remove new headers, and upper layer device Can be delivered to.

The new layer device of the receiving end indicates that the S field of the new header of the currently received data indicates 0, has the same serial number as the currently received serial number among the previously received data, and the S field of the header indicates 1 If there is no data, that is, if the S field of the header of the previously received data was set to 0, it indicates that the currently received data is complete data that has not been split, so the new header is removed and the complete data is sent to the upper layer device. Can pass.

The new layer device of the receiving end checks and removes and reassembles the new header of the data if the S field of the new header of the currently received data indicates 1 (if there is a segmented data (segment) or another segment). It is stored in the buffer until data arrives until it is executed or has the same serial number as the segment and the S field of the header is set to zero. The received segments are reassembled and composed of complete data, which can be discarded from the buffer when delivered to the upper layer device.

1i to 1i-22 show a second to sixth embodiment of a data division method and a reassembly method of upper layer data.

In the second to sixth embodiments, a 1-bit segmentation field may be defined and used by the transmitting end and the receiving end. The S field may be defined to indicate the complete data (or the last segment) that is not divided, and the segment other than the last segment (or indicating that there is another segment) for the number of two cases of 0 and 1, respectively. There are two types of one-to-one mapping of the number of 2 cases in the S field of 0 and 1, complete data that is not split (or the last segment), and a segment other than the last segment (or indicating that there is another segment). Can be defined as one of them. For example, the S field can be defined as shown in [Table 9] below.

[Table 9]

As illustrated in FIG. 1G, the newly defined new layer device (SEG layer, SEG layer device) is defined and used above the PDCP layer device, and thus, when the receiving RLC layer device operates in the AM mode, it supports data transmission without loss and , The receiving PDCP layer device sorts the data in order based on the PDCP serial number and delivers it to the receiving SEG layer device. However, when the receiving RLC layer device is operated in UM mode to allow loss, or data transmission between the RLC layer device and the PDCP layer device is wireless or wired due to the implementation of the CU-DU split structure of the base station, data is lost. If this occurs, the new layer device needs the serial number, and even if the loss occurs only when the serial number is used with the 2-bit S field, the RRC message or data is split at the transmitting end, and the partitioned data is successfully received at the receiving end. It can be reassembled and received.

The operation of the transmitting end in the second to sixth embodiments of the data division method and the reassembly method of the upper layer data is as follows.

The new layer device does not perform data segmentation if the size of the RRC message or data received from the higher layer device is greater than the maximum size or a specific threshold supported by the PDCP layer device, and if not, the data segmentation is not performed.

In the 2-5th embodiment, when serial numbers are allocated, different serial numbers may be assigned to divided data (segments) that have been divided for the same upper layer data (SEG SDU). Accordingly, the serial number indicates the order of each segment, and the S field can indicate from which part of the data the segments are divided. Therefore, even if 3 or more segments are divided for one and the same data, and the 1st or 2nd segment is lost, the 2nd or 3rd segment lost at the receiving end can be distinguished using a serial number, and the presence or absence of detection can be detected. Can. However, since the S field has only one bit indicator, if the last segment is lost, it may have a problem that re-assembly cannot be performed on the data after which the last segment is lost and the next data. Therefore, the 1-bit indicator is a useful method when there is no loss that the RLC layer device operates in the RLC AM mode.

The new layer device of the transmitting end assigns different serial numbers to segments if data division is performed, sets the S field of the new header to 1 if it is not the last division data (segment), and sets the header before the division data. Attach and forward to lower layer devices. And in the case of the last segmented data (segment) (or in the case of complete unpartitioned data), set the S field of the new header to 0, attach the header before the last segmented data (or complete segmented data) and lower layer To the device.

If data division is not performed, the serial number is assigned, and the S field of the new header is set to 0 for data received from the upper layer, the header is attached in front of the data, and it is transmitted to the lower layer device.

The operation of the receiving end for the second to sixth embodiments of the data division method and the reassembly method of upper layer data is as follows.

When a new layer device is set for a specific bearer (SRB or DRB) or when a data division method and a reassembly method described in the present disclosure are set, the new layer device at the receiving end reads a new header, and the information indicated by the header Check to see if there is no last segmented data (segment) or complete segmented data or another segment, or if there is segmented data (segment) or another segment. And it can be seen that the serial number indicates the order of different segments. Therefore, when the gap of the serial number occurs, it can be seen that the loss occurred.

The new hierarchical device of the receiving end indicates that the S field of the new header of the currently received data indicates 0 (i.e., the last segmented data (segment) or complete undivided data or no other segment) and the currently received series. If the S field of the number and header is set to 0 and is smaller than the currently received serial number and there is no serial number gap between the largest serial number among the data received so far, and the serial number currently received since the largest serial number If there are data (segments) in which the S field of the header is set to 1, the data can be reassembled in the order in which they were received together with the currently received data to construct complete data, remove new headers, and deliver it to the upper layer device.

The new hierarchical device of the receiving end indicates that the S field of the new header of the currently received data indicates 0, and the currently received serial number and the S field of the header are set to 0, and is smaller than the currently received serial number and received so far. If there is no serial number gap between the largest serial numbers among the data, and there is no data (segment) in which the S field of the header is set to 1 between the serial numbers currently received since the largest serial number, the new header of the currently received data is displayed. It can be removed and delivered to higher layer devices.

The new layer device of the receiving end checks and removes and reassembles the new header of the data if the S field of the new header of the currently received data indicates 1 (if there is a segmented data (segment) or another segment). Until this is performed or by checking the serial number and S field, it is stored in a buffer until all segments are received for one data (SEG SDU). Here, the reassembly procedure may be performed when all segments are received for one data (SEG SDU) by checking the serial number and the S field. Here, the received segments are reassembled and composed of complete data, and then transmitted to a higher layer device, and thus discarded from the buffer.

When the terminal or the base station performs the data division method and the re-assembly method of the upper layer data according to an embodiment, the data division may be performed in units of bytes to facilitate re-assembly of the receiving end. Further, when the size of data received from the upper layer device exceeds a specific threshold value and performs a segmentation procedure, the transmission end may be divided into segments having a fixed size or the same size, thereby facilitating processing of the receiving end. have. As another method, header overhead can be reduced by allowing the transmitting end to divide into segments having a variable size when the size of the data received from the upper layer device exceeds a specific threshold and performs a partitioning procedure. As another method, when the size of data received from the upper layer device exceeds a specific threshold and performs a partitioning procedure, it is left to the terminal implementation or the network implementation to divide into segments having a size. Here, the specific threshold may be set by the base station as an RRC message.

When a terminal or a base station performs a data division method and a reassembly method of upper layer data according to an embodiment, an indicator may be defined in a header to instruct that all segments that have not been reassembled among previously received segments be discarded. .

When applying the data division method and re-assembly method of the upper layer data according to an embodiment in a new layer device, a new header may be generated and transmitted to the lower PDCP layer device together with data received from the upper layer.

At this time, the lower PDCP layer device may apply one of the following methods when performing an encryption procedure or an integrity protection procedure on upper layer data.

Method 1: For convenience of terminal implementation, new headers of new layer devices for data division and reassembly of upper layer data are always encrypted for SRB and DRB. In addition, integrity protection procedure is always performed on the new header.

Method 2: The new header of the new layer device for data division and reassembly of higher layer data is not encrypted for the SRB and the DRB so that the receiving end can read the information of the new header early before decryption. And the integrity protection procedure is always performed on the new header.

Method 3: For convenience of terminal implementation, for the SRB, a new header of a new layer device for data division and reassembly of upper layer data is always encrypted. However, when the SDAP header is set for the DRB, since the SDAP header needs to be unencrypted, the new header is located in the PDCP header and the SDAP header, and encryption may be performed twice unnecessarily, and the encryption procedure may be complicated. . Therefore, for the DRB, a new header of a new layer device for data division and reassembly of higher layer data may not be encrypted. And, the integrity protection procedure is always performed on the new header.

Method 4: For convenience of terminal implementation, the DRB always encrypts a new header of a new layer device for data division and reassembly of higher layer data. However, for the SRB, the new header of the new layer device for data division and reassembly of the upper layer data is not encrypted so that the receiving end can read the information of the new header early before decoding. And, the integrity protection procedure is always performed on the new header.

1-1 embodiment, 1-2 embodiment, 1-3 embodiment, 2-1 embodiment, 2-2 embodiment, 2nd embodiment of the data division method and re-assembly method of upper layer data -3 embodiments, 2-4 embodiments, 2-5 embodiments, 2-6 embodiments are applied to other layer devices, for example, RRC layer device or SDAP layer device or PDCP layer device or RLC It may be introduced and used in a layer device. When the embodiments are applied to other layer devices, the new layer device in the above description may be interpreted as another layer device. That is, the 2-bit indicator or the 1-bit indicator can be defined in the header of another layer device and the above-described embodiments can be applied. If the serial number already exists, the above-described embodiments can be applied using the existing serial number. have. If there is no serial number, embodiments may be applied by defining a new serial number in a header in another layer device and defining a 2-bit indicator or a 1-bit indicator. In addition, when an indication of the length is required, an L field indicating the length can also be defined and used. In addition, when the embodiments are applied to other layer devices, the newly defined header fields (serial number or 2-bit indicator or 1-bit indicator) are used only when a data division method and a re-assembly method of upper layer data are used. The overhead can be reduced by defining and using a new indicator in the header indicating whether the newly defined header fields are present or not.

1J is a diagram illustrating a procedure for processing data when an upper layer header compression procedure or integrity protection is set according to an embodiment.

In FIG. 1J, each bearer of a terminal or a base station may set a PDCP layer device and perform data processing. If the integrity protection and verification procedure is set in the bearer or logical channel or PDCP layer device as the RRC message or the header compression procedure is set or the SDAP layer device is set as described in FIG. 1E, the data processing procedure is shown in FIG. 1J. It can be performed as follows.

In FIG. 1J, when the SDAP layer device receives data from the upper layer device, it can check the QoS flow, generate and concatenate the SDAP header, and transfer the data to the bearer or PDCP layer device mapped thereto. When a header compression procedure (ROHC, Robust Header Compression) is set, the PDCP layer device receiving the data performs a header compression procedure for headers of a higher layer device than the SDAP layer device, except for the SDAP header from the data received from the upper layer. Perform and generate the PDCP header to configure the data (PDCP PDU) (1j-10). Then, if the integrity protection and verification procedure is set, the integrity protection procedure is performed on the PDCP header, the SDAP header, the compressed header and the data (1j-15), and the MAC-I having a predetermined length is calculated, followed by the data. By joining and performing an encryption procedure (1j-20), data processing of the PDCP layer device can be completed and data can be transferred to the lower layer device.

In the present disclosure, a procedure considering a header compression procedure (ROHC) may be extended and applied to a user data compression procedure (UDC, Uplink data compression) or a new header or data compression procedure of a PDCP layer device.

Below, in one embodiment, a data division method and a reassembly method of upper hierarchical data (eg, 1-1 embodiment, 1-2 embodiment, 1-3 embodiment, 2-1 embodiment, Efficiently process data according to where the 2-2 embodiment, 2-3 embodiment, 2-4 embodiment, 2-5 embodiment, and 2-6 embodiment) are performed in the protocol layer device Describe the methods you can handle.

1K is a diagram illustrating a third embodiment of efficiently processing data in a PDCP layer device according to an embodiment when the first embodiment or the second embodiment is applied to a new layer device located above the PDCP layer device. .

In the third embodiment, the data division method and the re-assembly method of the upper layer data described above (for example, the 1-1 embodiment, the 1-2 embodiment, the 1-3 embodiment, and the 2-1 embodiment) , 2-2 embodiment, 2-3 embodiment, 2-4 embodiment, 2-5 embodiment, 2-6 embodiment) in the new layer device (1k-05) on the PDCP layer device When applied, the header compression and decompression procedure or the integrity protection and verification procedure or the encryption and decryption procedure will be described as follows.

-Transmitting PDCP layer device: When the transmitting PDCP layer device receives data from a higher layer device that performs a segmentation operation, it checks the header of the upper layer device to determine whether the data is undivided data or the first data that is divided. By distinguishing whether it is the divided intermediate or last data, data processing can be performed differently as follows.

● If the data is unpartitioned or the first part of the partitioned data (or the first partitioned fragment) (1k-10, 1k-20):

If the SDAP layer device has been set and the header compression procedure has been set, the PDCP layer device has headers of upper layer devices (eg, TCP/IP layer device headers or UDP headers) excluding SDAP headers for convenience of terminal implementation in the corresponding data. Alternatively, a header compression procedure may be applied and performed on other upper layer device headers). As another method, the header of the upper layer device (for example, the TCP/IP layer device header) except for the header of the SEG layer device including the SDAP header and the segmentation information of the upper layer device so that the receiving end can read the segmentation information before decoding. Alternatively, a header compression procedure may be applied and performed on a UDP header or other upper layer device header. And, if integrity protection is set, integrity protection can be applied to headers and data. Here, after the header compression procedure is applied, for the convenience of the terminal implementation for the headers and data, an encryption procedure may be performed on the remaining headers and data except the SDAP header. As another method, an encryption procedure may be performed only on the compressed header and data other than the header of the SEG layer device including the SDAP header and the segmentation information of the upper layer device so that the receiving end can read the segmentation information before decoding.

● When the data is divided into intermediate or last data (1k-15, 1k-25):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device does not apply the header compression procedure because the data does not include the SDAP header or headers of higher layer devices such as TCP/IP or UDP layer devices. Does not. And, if integrity protection is set, integrity protection can be applied to headers and data. And, for the convenience of terminal implementation, it is possible to perform an encryption procedure on both the header and the data. As another method, an encryption procedure may be performed only on the remaining data except the header of the SEG layer device including the segmentation information of the upper layer device so that the receiving end can read the segmentation information before decoding.

-Receiving PDCP layer device: When receiving data from a lower layer device, the receiving PDCP layer device checks the header of the upper layer device to determine whether the corresponding data is undivided data, or is the first data that is divided, or the divided intermediate or last data. By distinguishing perception, data processing can be performed differently as follows. If the header including the segmentation information is encrypted, the header decompression process may be performed by classifying the undivided data, the first segmented data, or the segmented intermediate or last data as follows.

● If the data is unpartitioned or the first part of the partitioned data (or the first partitioned fragment) (1k-10, 1k-20):

A decoding procedure may be performed on the remaining headers and data excluding the SDAP header from the corresponding data. Alternatively, the decoding procedure may be performed only on the compressed header and data other than the header of the SEG layer device including the SDAP header and the segmentation information of the upper layer device. And, if integrity protection is set, integrity verification can be applied to headers and data. Here, after the decoding procedure is performed, if the SDAP layer device is set and the header compression procedure is set, the PDCP layer device header of the upper layer device (eg, TCP/IP layer device header or UDP) excluding the SDAP header from the data. Header or other higher layer device header). Alternatively, headers of higher layer devices (e.g., TCP/IP layer device headers or UDP headers or other higher layer device headers), except SDAP headers and headers of SEG layer devices containing segmentation information of higher layer devices. Decompression procedures can be applied and performed.

If the data is split middle or last data (1k-15, 1k-25):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device decrypts both the header and the data because the corresponding data does not include the SDAP header or headers of higher layer devices such as TCP/IP or UDP layer devices. Procedures can be performed, and if integrity protection is set, integrity verification can be applied to headers and data. As another method, the receiving end may perform the decoding procedure only on the rest of the data except for the header of the SEG layer device including the segmentation information of the higher layer device.

In the above-described third embodiment, it is characterized in that different data processing procedures are performed by dividing the unsegmented data or the first data or the intermediate or last data. That is, the header compression and decompression procedure is applied to the unsegmented data or the first segmented data, and the encryption and decryption procedures are performed in consideration of the SDAP header or the header of the new layer device, and the divided intermediate or last data is applied. For this, the header compression and decompression procedures are not applied, and the encryption and decryption procedures can be performed without considering the SDAP header or the header of the new layer device.

FIG. 1L shows that when the first embodiment or the second embodiment is applied to the PDCP layer device, and the partitioning method according to an embodiment is performed before the header compression procedure or the integrity protection or encryption procedure, the PDCP layer device efficiently processes data. It is a figure showing the fourth embodiment to be processed.

In the fourth embodiment, the data division method and the re-assembly method of the upper hierarchical data described above (for example, the 1-1 embodiment, the 1-2 embodiment, the 1-3 embodiment, and the 2-1 embodiment) When applying the 2nd embodiment, the 2-3 embodiment, the 2-4 embodiment, the 2-5 embodiment, and the 2-6 embodiment) in the PDCP layer device, the partitioning method is header compression. When it is performed before the procedure or integrity protection or encryption procedure, the header compression and decompression procedure or the integrity protection and verification procedure or the encryption and decryption procedure is proposed as follows.

-Transmitting PDCP layer device: When receiving data from the upper layer device, the transmitting PDCP layer device performs a partitioning procedure for data larger than the size supported by the PDCP layer device, and for data smaller than the size supported by the PDCP layer device. The partitioning procedure may not be performed. Then, after performing the segmentation procedure, the PDCP header instructs the segmentation information to each data, and distinguishes whether the corresponding data is unsegmented data, or the first data or the intermediate or last data, and then processes the data. You can do it differently like

● If the data is unsegmented data or the first segmented data (or the first segmented fragment) (1l-10):

If the SDAP layer device has been set and the header compression procedure has been set, the PDCP layer device has headers of upper layer devices (eg, TCP/IP layer device headers or UDP headers) excluding SDAP headers for convenience of terminal implementation in the corresponding data. Alternatively, a header compression procedure may be applied and performed on other upper layer device headers). And, if integrity protection is set, integrity protection can be applied to headers and data. After the header compression procedure is applied, for the convenience of the terminal implementation for the headers and data (because it is the same as the existing implementation method), the encryption procedure for the remaining headers (headers of higher layer devices) and data except the SDAP header You can do

● If the data is divided into intermediate or last data (1l-15):

If the SDAP layer device is configured and the header compression procedure is set, the PDCP layer device does not apply the header compression procedure because the corresponding data does not include SDAP headers or headers of higher layer devices such as TCP/IP or UDP layer devices. . And, if integrity protection is set, integrity protection can be applied to headers and data. And, for the convenience of terminal implementation, it is possible to perform an encryption procedure on both the header and the data.

-Receiving PDCP layer device: When receiving data from a lower layer device, the receiving PDCP layer device checks the header of the PDCP layer device to determine whether the corresponding data is undivided data, or is the first data that is divided, or the divided intermediate or last data. By distinguishing perception, data processing can be performed differently as follows.

● If the data is unsegmented data or the first segmented data (or the first segmented fragment) (1l-10):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device may apply and perform a decoding procedure on data excluding the SDAP header from the data. In addition, if integrity protection is set, integrity verification is performed after the decryption procedure is applied, and when integrity verification is successfully performed, headers of a higher layer device (eg, a TCP/IP layer device header or a SDAP header) for headers A header decompression procedure may be performed on a UDP header or other upper layer device header). Here, if the integrity verification fails, the data can be discarded. Or, you can discard the data and request a retransmission.

● If the data is divided into intermediate or last data (1l-15):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device decrypts both the header and the data because the corresponding data does not include the SDAP header or headers of higher layer devices such as TCP/IP or UDP layer devices. Procedures can be performed, and if integrity protection is set, integrity verification can be applied to headers and data. And the header decompression procedure is not applied.

-In another method, the receiving PDCP layer device performs decoding procedures differently by distinguishing whether the received data is undivided data, the first divided data, or the divided intermediate or last data, In the header decompression procedure, the header decompression procedure may be performed only after complete data is generated by performing a reassembly procedure on the divided data. That is, if fragmented pieces of data are not completely received, data may be discarded, thereby preventing unnecessary decompression of the header. On the other hand, if the header decompression procedure is performed on each segmented data before reassembly, the data processing processing time can be shortened.

In the above-described fourth embodiment, it is characterized in that different data processing procedures are performed by dividing unsegmented data or divided first data or divided intermediate or last data. That is, the header compression and decompression procedure is applied to the unpartitioned data or the first segmented data, and the encryption and decryption procedures are performed in consideration of the SDAP header, and the header compression and decompression is performed on the segmented intermediate or final data. Without applying the procedure, the encryption and decryption procedure can be performed without considering the SDAP header.

FIG. 1M is a PDCP layer device when the first embodiment or the second embodiment is applied to a PDCP layer device, a partitioning method according to an embodiment is performed after a header compression procedure, and is performed before a integrity protection or encryption procedure. It is a figure showing a fifth embodiment for efficiently processing data.

In the fifth embodiment, the data division method and the re-assembly method of the upper layer data described above (for example, the 1-1 embodiment, the 1-2 embodiment, the 1-3 embodiment, and the 2-1 embodiment) When applying the 2nd embodiment, the 2-3 embodiment, the 2-4 embodiment, the 2-5 embodiment, and the 2-6 embodiment) in the PDCP layer device, the partitioning method is header compression. When it is performed after the procedure and before the integrity protection or encryption procedure, the header compression and decompression procedure or the integrity protection and verification procedure or the encryption and decryption procedure will be described as follows.

-Transmitting PDCP layer device: If the receiving PDCP layer device receives data from the upper layer device, if the SDAP layer device or header compression procedure is set, the compressed data after performing the header compression procedure on the upper layer device header except the SDAP header A partitioning procedure may be performed on data whose size is larger than the size supported by the PDCP layer device, and a partitioning procedure may not be performed on data smaller than the size supported by the PDCP layer device. Then, after performing the segmentation procedure, the PDCP header instructs the segmentation information to each data, and distinguishes whether the corresponding data is unsegmented data, or the first data or the intermediate or last data, and then processes the data. You can do it differently like

● If the data is unpartitioned or the first part of the data (or the first segment of the fragment) (1m-10):

If the SDAP layer device is configured, and the header compression procedure is set and integrity protection is set, integrity protection can be applied to the header and data. Here, after the header compression procedure or the integrity protection procedure is applied, for the convenience of the terminal implementation for the headers and data (because it is the same as the existing implementation method), the remaining headers (the headers or compression of higher layer devices) except the SDAP header Headers) and data.

● When the data is divided into intermediate or last data (1m-15):

If the SDAP layer device is configured, and the header compression procedure is set and integrity protection is set, integrity protection can be applied to the header and data. Since the PDCP layer device does not include SDAP headers or headers of higher layer devices such as TCP/IP or UDP layer devices, encryption procedures for both headers and data are performed for convenience of terminal implementation without considering SDAP headers. It can be done.

-Receiving PDCP layer device: When receiving data from a lower layer device, the receiving PDCP layer device checks the header of the PDCP layer device to determine whether the corresponding data is undivided data, or is the first data that is divided, or the divided intermediate or last data. By distinguishing perception, data processing can be performed differently as follows.

● If the data is unpartitioned or the first part of the data (or the first segment of the fragment) (1m-10):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device may apply and perform a decoding procedure on data excluding the SDAP header from the data. In addition, if integrity protection is set, integrity verification is performed after the decryption procedure is applied, and when integrity verification is successfully performed, headers of a higher layer device (eg, a TCP/IP layer device header or a SDAP header) for headers A header decompression procedure may be performed on a UDP header or other upper layer device header). Here, if the integrity verification fails, the data can be discarded. Or, you can discard the data and request a retransmission.

● When the data is divided into intermediate or last data (1m-15):

If the SDAP layer device is set and the header compression procedure is set, the PDCP layer device decrypts both the header and the data because the corresponding data does not include the SDAP header or headers of higher layer devices such as TCP/IP or UDP layer devices. Procedures can be performed, and if integrity protection is set, integrity verification can be applied to headers and data. And the header decompression procedure is not applied.

-In another method, the receiving PDCP layer device performs decoding procedures differently by distinguishing whether the received data is undivided data, the first divided data, or the divided intermediate or last data, In the header decompression procedure, the header decompression procedure may be performed only after complete data is generated by performing a reassembly procedure on the divided data. That is, if fragmented pieces of data are not completely received, data may be discarded, thereby preventing unnecessary decompression of the header. On the other hand, if the header decompression procedure is performed on each segmented data before reassembly, the data processing processing time can be shortened.

In the above-described fifth embodiment, it is characterized in that different data processing procedures are performed by dividing the unsegmented data or the divided first data or the divided intermediate or last data. That is, the header compression and decompression procedure is applied to the unpartitioned data or the first segmented data, and the encryption and decryption procedures are performed in consideration of the SDAP header, and the header compression and decompression is performed on the segmented intermediate or final data. Without applying the procedure, the encryption and decryption procedure can be performed without considering the SDAP header.

FIG. 1N shows that when the first embodiment or the second embodiments are applied in a PDCP layer device, and the partitioning method according to an embodiment is performed after a header compression procedure or an integrity protection or encryption procedure, data from the PDCP layer device is efficiently performed. It is a figure showing the sixth embodiment to be processed.

In the fifth embodiment, the data division method and the re-assembly method of the upper layer data described above (for example, the 1-1 embodiment, the 1-2 embodiment, the 1-3 embodiment, and the 2-1 embodiment) When applying the 2nd embodiment, the 2-3 embodiment, the 2-4 embodiment, the 2-5 embodiment, and the 2-6 embodiment) in the PDCP layer device, the partitioning method is header compression. When performed after the procedure or integrity protection or encryption procedure, the header compression and decompression procedure or the integrity protection and verification procedure or the encryption and decryption procedure will be described as follows.

-Transmitting PDCP layer device: If the transmitting PDCP layer device receives data from the upper layer device, if the SDAP layer device or header compression procedure is set, if the header compression procedure is performed on the upper layer device header except the SDAP header and integrity protection is set. Applied, except for the SDAP header, the size of the encrypted data is greater than the size supported by the PDCP layer device, and the data is smaller than the size supported by the PDCP layer device. It may not. Then, after performing the partitioning procedure, the PDCP header instructs the partitioning information to each data, distinguishes whether the data is unpartitioned data, or is the first partitioned data or the partitioned intermediate or last data, and identifies each PDCP header. Create and deliver to the lower layer and perform the transmission.

-Receiving PDCP layer device: When receiving data from a lower layer device, the receiving PDCP layer device checks the header of the PDCP layer device to determine whether the corresponding data is undivided data, or is the first data that is divided, or the divided intermediate or last data. By distinguishing the recognition, it is possible to reassemble the segmented data into complete data based on the PDCP serial number of the PDCP header and the segmentation information indicator. Here, for the reassembled data, a decoding procedure may be performed except for the SDAP header and a header decompression procedure may be performed except for the SDAP header. Alternatively, in order to accelerate data processing, decoding may be performed at a segmented data level before reassembly (Segment-level deciphering), and the data is not divided or the first segmented data (or In the case of the first segment) (1n-10) If the SDAP layer device has been set and the header compression procedure has been set, the header of the upper layer device excluding the SDAP header for the headers (eg, TCP/IP layer device) Header or UDP header or other upper layer device header). If the corresponding data is divided into intermediate or last data (1n-15), if the SDAP layer device is set and the header compression procedure is set, the PDCP layer device has a higher level, such as an SDAP header or TCP/IP or UDP layer device. Since the header of the layer devices is not included, the header decompression procedure is not applied.

That is, the receiving PDCP layer device performs different decoding procedures by distinguishing whether the corresponding data is undivided data, the first divided data, or the divided intermediate or last data, and receives headers. The decompression procedure may perform the header decompression procedure only after the complete data is created by performing the reassembly procedure on the divided data. That is, if fragmented pieces of data are not completely received, data may be discarded, thereby preventing unnecessary decompression of the header. On the other hand, if the header decompression procedure is performed on each segmented data before reassembly, the data processing processing time can be shortened.

In the above-described sixth embodiment, the same data processing procedure is performed after the re-assembly in the receiving PDCP layer device before the segmentation in the transmitting PDCP layer device without distinguishing the unsegmented data or the first data segmentation or the segmented intermediate or last data. It is characterized by. When another method is applied, in the sixth embodiment, different data processing procedures may be performed by dividing unsegmented data, divided first data, or divided intermediate or last data.

In the above-described embodiments, the procedure considering the header compression procedure (ROHC) may be extended and applied to a new header or data compression procedure of a user data compression procedure (UDC, Uplink data compression) or a PDCP layer device. However, if the compression procedure is applicable to data as well as the header, the compression procedure of the PDCP layer device can always be applied to all of the corresponding data, without distinguishing the first or middle or last segment or unsegmented data, and encryption And the decryption procedure can be applied by classifying data as in the third or fourth or fifth or sixth embodiment. In addition, in the above-described embodiments, the new layer device or the PDCP layer device may discard the segmented data if it is not reassembled until the timer defined in the new layer device or the reordering timer of the PDCP layer device expires. .

1O is a diagram illustrating an operation of a transmitting end of a terminal for a data division method and a reassembly example of upper layer data according to an embodiment.

The size of the RRC message or data (1o-05) received from the upper layer device is greater than or less than the maximum size or a specific threshold (configurable as an RRC message) supported by the PDCP layer device. It is possible to determine whether it is necessary to divide based on the criteria (1o-10). If the size of the RRC message or data received from the upper layer device is larger than a specific threshold, data division is performed, and if not, data division is not performed. The transmission layer device may assign a serial number to segments if data segmentation has been performed, and set a segmentation information indicator for each segment. Also, if data division is not performed, a serial number can be assigned to the complete data and the division information indicator can be set accordingly. In addition, data may be classified and processed as in the above-described third or fourth or fifth or sixth embodiment. That is, the third embodiment or the second data processing procedure is described by classifying the data processing (1o-20) and the divided intermediate or last data (1o-25) for the unsegmented data or the first data that is divided. It can be performed as in the fourth embodiment or the fifth embodiment or the sixth embodiment.

1P is a diagram illustrating an operation of a receiving end of a terminal for a data division method and a reassembly example of upper layer data according to an embodiment.

The reception layer device 1p-01 may check whether the data is divided by checking the header of the RRC message or data 1p-05 received from the lower layer device. In addition, it is possible to distinguish whether the received data is undivided data, first divided data, or divided intermediate or last data through a procedure for checking whether the data is divided. In addition, data may be classified and processed as in the above-described third or fourth or fifth or sixth embodiment. That is, the third embodiment or the second data processing procedure is described by distinguishing data processing (1p-20) and divided intermediate or last data (1p-25) for undivided data or first divided data. It can be performed as in the fourth embodiment or the fifth embodiment or the sixth embodiment.

1Q is a block diagram showing the configuration of a terminal or a wireless node according to an embodiment.

Referring to Figure 1q, the above-described terminal includes a radio frequency (RF) processor 1q-10, a baseband processor 1q-20, a storage unit 1q-30, and a controller 1q-40 do.

The RF processing unit 1q-10 may perform a function for transmitting and receiving a signal through a wireless channel such as band conversion and amplification of the signal. That is, the above-described RF processing unit 1q-10 converts the baseband signal provided from the above-described baseband processing unit 1q-20 to an RF band signal, transmits it through an antenna, and receives it through the above-described antenna. The RF band signal can be down-converted to a baseband signal. For example, the above-described RF processing unit 1q-10 includes a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), and an analog to digital converter (ADC). can do. In the above-described drawings, only one antenna is shown, but the above-described terminal may include a plurality of antennas. Also, the RF processing unit 1q-10 described above may include a plurality of RF chains. Furthermore, the above-described RF processing unit 1q-10 may perform beamforming. For the above-described beamforming, the above-described RF processing unit 1q-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. In addition, the above-described RF processor may perform multi input multi output (MIMO), and may receive multiple layers when performing MIMO operation. The RF processing unit 1q-10 described above performs reception beam sweeping by appropriately setting a plurality of antennas or antenna elements under the control of the control unit, or adjusts the direction and beam width of the reception beam so that the reception beam is coordinated with the transmission beam. Can.

The baseband processing unit 1q-20 may perform a conversion function between a baseband signal and a bit stream according to a physical layer standard of the system. For example, when transmitting data, the baseband processor 1q-20 may generate complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit 1q-20 may restore the received bit stream through demodulation and decoding of the baseband signal provided from the RF processing unit 1q-10. For example, in the case of conforming to the orthogonal frequency division multiplexing (OFDM) method, when transmitting data, the baseband processor 1q-20 generates complex symbols by encoding and modulating a transmission bit string and mapping the complex symbols to subcarriers. After that, OFDM symbols may be configured through an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the above-described baseband processing unit 1q-20 divides the baseband signal provided from the RF processing unit 1q-10 in units of OFDM symbols, and transmits to the subcarriers through fast Fourier transform (FFT) operation. After restoring the mapped signals, the received bit stream may be reconstructed through demodulation and decoding.

The baseband processing unit 1q-20 and the RF processing unit 1q-10 transmit and receive signals as described above. Accordingly, the baseband processing unit 1q-20 and the RF processing unit 1q-10 may be referred to as a transmission unit, a reception unit, a transmission/reception unit, or a communication unit. Furthermore, at least one of the baseband processing unit 1q-20 and the RF processing unit 1q-10 may include a plurality of communication modules to support a plurality of different radio access technologies. In addition, at least one of the baseband processing unit 1q-20 and the RF processing unit 1q-10 may include different communication modules to process signals of different frequency bands. For example, the different radio access technologies described above may include LTE networks, NR networks, and the like. In addition, the different frequency bands described above may include a super high frequency (SHF) band (eg, 2.2 gHz, 2ghz), and a millimeter wave (mm band) (eg, 60 GHz) band. The terminal may transmit and receive signals to and from the base station using the baseband processor 1q-20 and the RF processor 1q-10. Here, the signal may include control information and data.

The storage unit 1q-30 may store data such as a basic program, application program, and setting information for the operation of the above-described terminal. The storage unit 1q-30 may provide stored data according to the request of the control unit 1q-40 described above. The storage unit 1q-30 may be composed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM and a DVD, or a combination of storage media. Also, the storage unit 1q-30 may be configured with a plurality of memories. In one embodiment, the storage unit 1q-30 may store a program for supporting beam-based cooperative communication.

The control unit 1q-40 controls overall operations of the above-described terminal. For example, the control unit 1q-40 may transmit and receive signals through the baseband processing unit 1q-20 and the RF processing unit 1q-10. In addition, the control unit 1q-40 can record and read data in the storage unit 1q-40. To this end, the control unit 1q-40 may include at least one processor. For example, the control unit 1q-40 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls an upper layer such as an application program. According to an embodiment, the control unit 1q-40 may include a multiple connection processing unit 1q-42 configured to process a process operating in a multiple connection mode.

1R is a block diagram showing the configuration of a TRP device or a wireless node in a wireless communication system according to an embodiment.

Referring to FIG. 1R, the base station includes an RF processing unit 1r-10, a baseband processing unit 1r-20, a backhaul communication unit 1r-30, a storage unit 1r-40, and a control unit 1r-50. .

The RF processor 1r-10 may perform a function for transmitting and receiving a signal through a wireless channel such as band conversion and amplification of the signal. That is, the RF processor 1r-10 converts the baseband signal provided from the baseband processor 1r-20 to an RF band signal, transmits it through an antenna, and transmits the RF band signal received through the antenna described above. It can be down-converted to a baseband signal. For example, the RF processing unit 1r-10 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, and A DC. In the above-described drawings, only one antenna is shown, but the first access node may include a plurality of antennas. Also, the RF processing unit 1r-10 may include a plurality of RF chains. Furthermore, the RF processing unit 1r-10 may perform beamforming. For beamforming, the RF processing unit 1r-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. The above-described RF processor may perform a downlink MIMO operation by transmitting one or more layers.

The baseband processing unit 1r-20 may perform a conversion function between the baseband signal and the bit stream according to the physical layer standard of the first radio access technology. For example, when transmitting data, the baseband processor 1r-20 may generate complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit 1r-20 can restore the received bit stream through demodulation and decoding of the baseband signal provided from the RF processing unit 1r-10. For example, according to the OFDM method, when transmitting data, the baseband processor 1r-20 generates complex symbols by encoding and modulating the transmission bit string, mapping the complex symbols to subcarriers, and then performing IFFT operation and OFDM symbols can be configured through CP insertion. In addition, when receiving data, the baseband processing unit 1r-20 divides the baseband signal provided from the RF processing unit 1r-10 into OFDM symbol units and restores signals mapped to subcarriers through FFT calculation. , It is possible to restore the received bit stream through demodulation and decoding. The baseband processor 1r-20 and the RF processor 1r-10 may transmit and receive signals as described above. Accordingly, the baseband processor 1r-20 and the RF processor 1r-10 may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit.

The communication unit 1r-30 may provide an interface for performing communication with other nodes in the network. The base station may transmit and receive signals to and from the terminal using the baseband processor 1r-20 and the RF processor 1r-10. Here, the signal may include control information and data.

The storage unit 1r-40 may store data such as a basic program, an application program, and setting information for the operation of the main station described above. In particular, the storage unit 1r-40 may store information on bearers allocated to the connected terminal, measurement results reported from the connected terminal, and the like. In addition, the storage unit 1r-40 may store information that is a criterion for determining whether to provide or stop multiple connections to the terminal. Then, the storage unit 1r-40 may provide the stored data according to the request of the control unit 1r-50. The storage unit 1r-40 may be formed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM and a DVD, or a combination of storage media. Also, the storage unit 1r-40 may be configured with a plurality of memories. In one embodiment, the storage unit 1r-40 may store a program for supporting beam-based cooperative communication.

The control unit 1r-50 can control the overall operations of the main station. For example, the control unit 1r-50 may transmit and receive signals through the baseband processing unit 1r-20 and the RF processing unit 1r-10 or through the backhaul communication unit 1r-30. In addition, the control unit 1r-50 can record and read data in the storage unit 1r-40. To this end, the control unit 1r-50 may include at least one processor. According to an embodiment, the control unit 1r-50 may include a multiple connection processing unit 1r-52 configured to process a process operating in a multiple connection mode.

In the next-generation mobile communication system, base stations having various structures are possible, and various wireless access technologies can be mixed. In this situation, when transmitting data from each wireless node (IAB node or IAB donor or terminal) in a network structure that supports a wireless backhaul or Integrated Access Backhaul (IAB), check the errors that may occur in the wireless section and check the integrity. There is a need for methods to verify or enhance security.

In one embodiment of the present disclosure, a method for bearer operation and data processing of wireless nodes in a next-generation mobile communication system supporting wireless backhaul is described. In addition, it describes how to prevent data errors or unexpected attacks that may occur in a wireless link, and to strengthen integrity verification or security. More specifically, in order to enhance security in a wireless section from the top wireless node (for example, IAB donor) of the wireless backhaul network to the wireless node connected to the terminal, the security at the top wireless node and the wireless node connected to the terminal A procedure for setting a PDCP layer device for strengthening and setting an encryption and decryption procedure or an integrity protection or verification procedure will be described.

According to the disclosed embodiment, an error may be confirmed when data is transmitted in a wireless backhaul network (Integrated Access Backhaul), and security may be enhanced.

2A is a diagram showing the structure of an LTE system to which an embodiment is applied.

Referring to Figure 2a, the radio access network of the LTE system is a next-generation base station (Evolved Node B, hereinafter referred to as ENB, Node B or base station) (2a-05, 2a-10, 2a-15, 2a-20), MME (2a- 25, Mobility Management Entity) and S-GW (2a-30, Serving-Gateway). User equipment (hereinafter referred to as UE or UE) 2a-35 may access an external network through ENBs 2a-05 to 2a-20 and S-GW 2a-30.

In FIG. 2A, ENBs 2a-05 to 2a-20 may correspond to Node B of a Universal Mobile Telecommunication System (UMTS) system. ENB is connected to the UE (2a-35) by a radio channel and performs a more complicated role than Node B. In the LTE system, all user traffic, including real-time services such as Voice over IP (VoIP) through the Internet protocol, are serviced through a shared channel, so status information such as buffer status of UEs, available transmission power status, channel status, etc. It is necessary to have a device for scheduling by collecting, and the ENB (2a-05 ~ 2a-20) may be in charge. One ENB can usually control multiple cells. For example, in order to implement a transmission speed of 100 Mbps, the LTE system may use orthogonal frequency division multiplexing (OFDM) in a 20 MHz bandwidth, for example, as a radio access technology. In addition, an adaptive modulation & coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to a channel state of a terminal may be applied. S-GW (2a-30) is a device that provides a data bearer, and can create or remove a data bearer under the control of the MME (2a-25). The MME 2a-25 is a device in charge of various control functions as well as a mobility management function for a terminal, and may be connected to multiple base stations.

2B is a diagram illustrating a radio protocol structure in an LTE system to which an embodiment is applied.

Referring to Figure 2b, the radio protocol of the LTE system is the PDCP (Packet Data Convergence Protocol) (2b-05, 2b-40), RLC (Radio Link Control) (2b-10, 2b-35) in the terminal and the ENB, respectively. MAC (Medium Access Control) (2b-15, 2b-30). Packet Data Convergence Protocol (PDCP) (2b-05, 2b-40) is responsible for IP header compression/restore. The main functions of PDCP can be summarized as follows.

-Header compression and decompression (ROHC (RObust Header Compression) only)

-Transfer of user data

-In-sequence delivery of upper layer PDUs at PDCP re-establishment procedure for RLC AM (Acknowledged Mode)

-For split bearers in DC (only support for RLC AM): PDCP PDU routing for transmission and PDCP PDU reordering for reception)

-Duplicate detection of lower layer SDUs at PDCP re-establishment procedure for RLC AM

-Retransmission of PDCP SDUs at handover and, for split bearers in DC, of PDCP PDUs at PDCP data-recovery procedure, for RLC AM

-Encryption and decryption function (Ciphering and deciphering)

-Timer-based SDU discard function (Timer-based SDU discard in uplink.)

The radio link control (hereinafter referred to as RLC) (2b-10, 2b-35) may reconstruct an PDCP packet data unit (PDU) to an appropriate size to perform an automatic repeat request (ARQ) operation. The main functions of RLC can be summarized as follows.

-Data transfer function (Transfer of upper layer PDUs)

-ARQ function (Error Correction through ARQ (only for AM data transfer))

-Concatenation, segmentation and reassembly of RLC SDUs (only for UM and AM data transfer)

-Re-segmentation of RLC data PDUs (only for AM data transfer)

-Reordering of RLC data PDUs (only for UM and AM data transfer)

-Duplicate detection (Duplicate detection (only for UM and AM data transfer))

-Error detection function (Protocol error detection (only for AM data transfer))

-RLC SDU deletion function (RLC SDU discard (only for UM and AM data transfer))

-RLC re-establishment

The MACs 2b-15 and 2b-30 are connected to various RLC layer devices configured in one terminal, multiplex the RLC PDUs to the MAC PDU, and demultiplex the RLC PDUs from the MAC PDU. The main functions of MAC can be summarized as follows.

-Mapping function (Mapping between logical channels and transport channels)

-Multiplexing and demultiplexing function (Multiplexing/demultiplexing of MAC SDUs belonging to one or different logical channels into/from transport blocks (TB) delivered to/from the physical layer on transport channels)

-Scheduling information reporting function

-HARQ function (Error correction through HARQ)

-Priority handling between logical channels (Priority handling between logical channels of one UE)

-Priority handling between UEs (Priority handling between UEs by means of dynamic scheduling)

-MBMS service identification function

-Transport format selection function

-Padding function

The physical (PHY) layer (2b-20, 2b-25) channel-codes and modulates the upper layer data, makes it an OFDM symbol and transmits it to a radio channel, or demodulates and decodes an OFDM symbol received through the radio channel and performs channel decoding. It is possible to perform an operation for transferring to a layer.

2C is a diagram illustrating the structure of a next-generation mobile communication system to which an embodiment is applied.

Referring to Figure 2c, the next generation mobile communication system (hereinafter referred to as NR or 5G) radio access network is a next-generation base station (New Radio Node B, NR gNB or NR base station) (2c-10) and NR CN (2c-05, New) Radio Core Network). The user terminal (New Radio User Equipment, NR UE or terminal) 2c-15 may access an external network through the NR gNB 2c-10 and the NR CN 2c-05.

In FIG. 2C, NR gNB 2c-10 corresponds to an evolved node B (eNB) of an existing LTE system. The NR gNB (2c-10) is connected to the NR UE (2c-15) through a wireless channel and can provide a service superior to that of the Node B. In the next-generation mobile communication system, since all user traffic is serviced through a shared channel, a device is required to collect and schedule status information such as buffer status of UEs, available transmission power status, and channel status, and this is NR NB (2c-10) is in charge. One NR gNB 2c-10 usually controls multiple cells. In order to implement ultra-high-speed data transmission compared to the current LTE, it may have more than the existing maximum bandwidth, and orthogonal frequency division multiplexing (hereinafter referred to as OFDM) as a wireless access technology may additionally incorporate beamforming technology. . In addition, an adaptive modulation & coding (hereinafter referred to as AMC) scheme for determining a modulation scheme and a channel coding rate according to a channel state of a terminal may be applied. The NR CN 2c-05 may perform functions such as mobility support, bearer setup, and QoS (Quality of Service) setup. NR CN (2c-05) is a device that is responsible for various control functions as well as mobility management functions for a terminal, and can be connected to multiple base stations. In addition, the next generation mobile communication system can be interlocked with the existing LTE system, and the NR CN (2c-05) can be connected to the MME (2c-25) through a network interface. The MME 2c-25 may be connected to the existing base station eNB 2c-30.

2D is a diagram illustrating a radio protocol structure of a next-generation mobile communication system to which an embodiment is applied. .

Referring to Figure 2d, the radio protocol of the next-generation mobile communication system is NR Service Data Adaptation Protocol (SDAP) (2d-01, 2d-45), NR Packet Data Convergence Protocol (PDCP) (2d-05) at the terminal and the NR base station, respectively. , 2d-40), NR RLC (2d-10, 2d-35) and NR MAC (2d-15, 2d-30). The main functions of NR SDAP (2d-01, 2d-45) may include some of the following functions.

-Transfer of user plane data

-Mapping function between QoS flow and data bearer for uplink and downlink (mapping between a QoS flow and a DRB for both DL and UL)

-Marking QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

-Reflective QoS flow to DRB mapping for the UL SDAP PDUs for uplink SDAP PDUs.

For the above-described SDAP layer device, the UE can set whether to use the header of the SDAP layer device or the function of the SDAP layer device, for each PDCP layer device, for each bearer, or for each logical channel, as an RRC message. When the header is set, the terminal is uplinked and downlinked by NAS non-access stratum quality of service (NAS QoS) setting 1-bit indicator (NAS reflective QoS) and AS QoS reflection setting 1-bit indicator (AS reflective QoS) in the SDAP header. It can instruct to update or reset the QoS flow and mapping information for the data bearer. The SDAP header described above may include QoS flow ID information indicating QoS. The above-described QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

The main functions of the NR PDCP (2d-05, 2d-40) may include some of the following functions.

-Header compression and decompression (ROHC only)

-Transfer of user data

-In-sequence delivery of upper layer PDUs

-Out-of-sequence delivery of upper layer PDUs

-Reordering function (PDCP PDU reordering for reception)

-Duplicate detection of lower layer SDUs

-Retransmission of PDCP SDUs

-Encryption and decryption function (Ciphering and deciphering)

-Timer-based SDU discard function (Timer-based SDU discard in uplink.)

Here, the order reordering function of the NR PDCP device includes a function of reordering PDCP PDUs received from a lower layer in order based on a PDCP sequence number (SN) and a function of delivering data to a higher layer in reordered order. can do. Or, the reordering function of the NR PDCP device (reordering) does not take the order into account, the function of immediately transmitting, reordering the function to record the lost PDCP PDUs, and reporting the status of the lost PDCP PDUs to the transmitting side And at least one of a function for requesting retransmission for lost PDCP PDUs.

The main functions of the NR RLC (2d-10, 2d-35) may include some of the following functions.

-Data transfer function (Transfer of upper layer PDUs)

-In-sequence delivery of upper layer PDUs

-Out-of-sequence delivery of upper layer PDUs

-ARQ function (Error Correction through ARQ)

-Concatenation, segmentation and reassembly of RLC SDUs

-Re-segmentation of RLC data PDUs

-Reordering of RLC data PDUs

-Duplicate detection function

-Protocol error detection

-RLC SDU deletion function (RLC SDU discard)

-RLC re-establishment

Here, the in-sequence delivery of the NR RLC device refers to a function of sequentially transmitting RLC SDUs received from a lower layer to an upper layer. In-sequence delivery of the NR RLC device is a function of reassembling and transmitting when one RLC SDU is originally divided into several RLC SDUs and receiving RLC PDUs through RLC sequence number ) Or PDCP reordering based on SN (sequence number), the ability to rearrange the order to record the lost RLC PDUs, the ability to report the status of the lost RLC PDUs to the sender, the lost RLC PDUs A function to request retransmission for a function, a function to deliver only RLC SDUs up to the previous layer in order, if there is a lost RLC SDU, or a timer if the specified timer expires even if there is a lost RLC SDU Includes the ability to deliver all RLC SDUs received before start to the upper layer in order, or to deliver all RLC SDUs received to the upper layer in order if the timer expires even if there is a missing RLC SDU. can do.

In addition, the out-of-sequence delivery function of the NR RLC device processes the RLC PDUs in the order in which they are received (regardless of the sequence number and sequence number order, in the order of arrival), and the sequence is sent to the PDCP device. It can be delivered regardless of (out-of-sequence delivery). In the case of segments, segments stored in a buffer or to be received at a later time can be received and reconstructed into a complete RLC PDU, processed, and then delivered to a PDCP device. The above-described NR RLC layer may not include a concatenation function, and may perform the above-described function in the NR MAC layer or replace it with a multiplexing function of the NR MAC layer.

The out-of-sequence delivery function of the NR RLC device may include a function of delivering RLC SDUs received from a lower layer directly to an upper layer regardless of order. The out-of-sequence delivery function of the RLC device is a function of reassembling and delivering when one RLC SDU is originally divided into several RLC SDUs, RLC SN of received RLC PDUs, or It may include at least one of a function of storing PDCP SNs and arranging the order to record lost RLC PDUs.

The NR MACs 2d-15 and 2d-30 may be connected to several NR RLC layer devices configured in one terminal, and the main function of the NR MAC may include some of the following functions.

-Mapping function (Mapping between logical channels and transport channels)

-Multiplexing/demultiplexing of MAC SDUs

-Scheduling information reporting function

-HARQ function (Error correction through HARQ)

-Priority handling between logical channels (Priority handling between logical channels of one UE)

-Priority handling between UEs (Priority handling between UEs by means of dynamic scheduling)

-MBMS service identification function

-Transport format selection function

-Padding function

The NR PHY layer (2d-20, 2d-25) channel-codes and modulates the upper layer data, makes it an OFDM symbol and transmits it to a radio channel, or demodulates and decodes an OFDM symbol received through the radio channel to the upper layer Transfer operation can be performed.

2E is a diagram illustrating a network structure supporting wireless backhaul considered in a next generation mobile communication system according to an embodiment.

Referring to FIG. 2E, an integrated access backhaul network (IAB) may be composed of a plurality of wireless nodes (eg, IAB node or IAB donor). In a wireless backhaul network, a terminal may connect to any wireless node to establish an RRC connection and transmit and receive data. In addition, each wireless node may consider another wireless node as a parent IAB node as a child IAB node, and establish and RRC connection with the parent wireless node to transmit and receive data. In one embodiment, the child radio node (child IAB node) may mean a terminal or an IAB node, and establish a radio connection connection from a parent radio node (parent IAB node or IAB donor), RRC configuration information, bearer configuration information, each It may refer to a wireless node that receives and applies configuration information of a PDCP or RLC or MAC or PHY layer device.

In one embodiment, the parent wireless node may mean an IAB node or an IAB donor. The parent radio node may refer to a radio node that sets radio connection connection settings, RRC configuration information, bearer configuration information, and configuration information of each PDCP or RLC or MAC or PHY layer device to a child radio node.

Referring to FIG. 2E, the IAB donor may refer to a wireless node connected to a core network, such as wireless node 1 (Node 1) 2e-01, to transmit data to an upper layer device. In addition, the IAB node is a wireless node 2 to wireless node 5 (Node 2 to Node 5) ((2e-02) to (2e) that serves to transmit data in the middle to help data transmission and reception between the terminal and the IAB donor end. -05)).

The terminals 2e-06, 2e-07, 2e-08, and 2e-09 may connect to wireless nodes (for example, an IAB node or IAB donor) to establish an RRC connection and transmit and receive data. For example, the terminal 2 (2e-07) may connect to the wireless node 3 (2e-03) to establish an RRC connection and transmit and receive data. Wireless node 3 (2e-03) receives data from terminal 2 (2e-07) or data to be transmitted to terminal 2 (2e-07) from wireless node 2 (2e-02), which is a parent wireless node, or wirelessly. Node 2 (2e-02). Further, the wireless node 2 (2e-02) transmits data received from the wireless node 3 (2e-03) or data to be transmitted to the wireless node 3 (2e-03), the wireless node 1 (IAB donor), which is the parent wireless node ( 2e-01) or wireless node 1 (2e-01).

Terminal 1 (2e-06) may connect to wireless node 2 (2e-02) to establish an RRC connection and transmit and receive data. The above-described wireless node 2 (2e-02) transmits data received from the above-described terminal 1 (2e-06) or data to be transmitted to the terminal 1 (2e-06), the wireless node 1 (2e-01) which is a parent wireless node. It can be received from or forwarded to the wireless node 1 (2e-01).

As described above, according to an embodiment, the terminal may connect to a wireless node having the best signal strength to establish an RRC connection, and transmit and receive data. In addition, according to one embodiment, the wireless backhaul network, the multi-hop through the intermediate wireless nodes, in order to enable the terminal to transmit data to the wireless node connected to the core network and receive data from the wireless node connected to the core network It can support (multi-hop) data transfer.

Figure 2f is a terminal in the wireless backhaul network (IAB) of the next-generation mobile communication system according to an embodiment when establishing a connection with a wireless node (IAB node or IAB donor) or a child wireless node is a parent wireless node (IAB node or IAB donor) ) And shows the procedure for performing RRC connection establishment when establishing a connection.

Referring to FIG. 2F, when a terminal or a child wireless node that transmits and receives data in an RRC connection mode does not transmit or receive data for a predetermined time or for a predetermined time, the parent wireless node sends a newly defined RRC message or RRCConnectionRelease message to the terminal or child. It may be transmitted to the wireless node to switch the terminal or child wireless node to the RRC idle mode or the RRC inactive mode (2f-01). In one embodiment, a terminal or a child wireless node (hereinafter referred to as an idle mode UE) in which a current connection is not established in the future is to perform an RRC connection establishment process with a parent wireless node when RRC idle mode occurs when data to be transmitted is generated. In the RRC deactivation mode, an RRC connection resume procedure with a parent radio node may be performed.

The terminal or the child radio node may establish a reverse transmission synchronization with the parent radio node through a random access process, and transmit a newly defined RRC message or RRC Connection Request message (or RRC Resume Request message) to the parent radio node (2f-05 ). The newly defined RRC message or RRC Connection Request message (or RRC Resume Request message) may include an identifier of a terminal or a child wireless node and a reason for establishing a connection (establishmentCause).

The parent wireless node may transmit a newly defined RRC message or RRCConnectionSetup message (or RRCResume message) so that the terminal or child wireless node establishes an RRC connection (2f-05). The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) includes at least one of configuration information for each logical channel, configuration information for each bearer, configuration information for PDCP layer devices, configuration information for RLC layer devices, and configuration information for MAC layer devices. Can be included.

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) indicates whether to perform retransmission to a target parent radio node or cell for pre-configured RRC messages when a terminal or a child radio node performs handover. You can set an indicator that indicates. For example, the parent radio node may instruct to perform retransmission on the RRC messages transmitted within a few seconds before receiving the handover indication message, before performing the handover, or before receiving the RRC message. have. In addition, the parent radio node may indicate an indicator for each of the RRC messages specified in advance. That is, multiple indicators may indicate whether to retransmit each RRC message. Alternatively, the parent radio node may indicate whether to retransmit in the form of a bitmap indicating each RRC message.

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may include an indicator to perform PDCP data recovery procedure in PDCP configuration information. In addition, the newly defined RRC message or RRCConnectionSetup message may include an indicator indicating whether to perform a PDCP data recovery procedure for a signaling radio bearer (SRB) or a data radio bearer (DRB) in bearer configuration information. In addition, the newly defined RRC message or RRCConnectionSetup message may include an indicator indicating whether to discard data remaining in the PDCP layer device for a signaling radio bearer (SRB) or a data radio bearer (DRB) in bearer configuration information. .

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may include an indicator indicating whether to perform cumulative retransmission or selective retransmission for AM DRB when performing PDCP re-establishment procedure, in bearer configuration information. .

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may include an indicator indicating which ARQ function to use in the child wireless node. The parent radio node may indicate whether to use a hop-by-hop ARQ function or an end-to-end ARQ function using the indicator. In addition, when setting the end-to-end ARQ function, whether the parent wireless node performs only a function of dividing or transmitting received RLC layer device data or performing an ARQ function as an end in a child node. You can also instruct. In addition, the parent wireless node may indicate which ARQ function to use as the default function. If the ARQ function is not set in the above-described message, hop-by-hop ARQ function or end-to-end ARQ function is used as the default function. You can also pre-set to use one of the features. In addition, the parent radio node may indicate whether the child radio node uses the data partitioning function using the newly defined RRC message or RRCConnectionSetup message, and whether each function of the RLC layer devices described with reference to FIG. 2B or 2D is activated. (Or use).

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may include an indicator indicating whether to use the data concatenation function in the Adaptation layer device. In addition, the newly defined RRC message or RRCConnectionSetup message may include an indicator indicating whether to set the header of the Adaptation layer device, and may specify the type of the header described above. For example, the parent wireless node can set which information to include in the header, such as a terminal identifier, a terminal bearer identifier, a QoS identifier, a wireless node identifier, a wireless node address, or QoS information using a newly defined RRC message or RRCConnectionSetup message. have. In one embodiment, the parent wireless node may be configured to omit the header to reduce overhead.

The parent radio node may be used between a transmitting Adaptation layer device and a receiving Adaptation layer device (ADAP) using a newly defined RRC message or RRCConnectionSetup message (or RRCResume message), or between a child wireless node and a parent wireless node, or a terminal. And an RLC channel to be used in the wireless node. Specifically, the RRCConnectionSetup message may include available number of RLC channels, available RLC channel identifier or mapping information of data mapped to the RLC channel (for example, terminal identifier, terminal bearer identifier, QoS information or QoS identifier mapping information). have. The RLC channel may be defined as a channel that bundles data of various terminals based on QoS information and delivers data according to QoS, and the RLC channel may also be defined as a channel that bundles data for each terminal and delivers data. .

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may include an indicator indicating whether to perform retransmission based on PDCP status reporting in the configuration information (pdcp-config) of the PDCP layer device. The parent wireless node may instruct to perform retransmission based on the PDCP status report using such an indicator. For example, when the above-described indicator value is set to 0, even if a PDCP status report is received, data corresponding to the NACK information of the PDCP status report may be checked and only data corresponding to the ACK information may be discarded. However, when the above-described indicator value is set to 1, upon receiving the PDCP status report, data corresponding to the ACK information of the PDCP status report may be discarded and data corresponding to the NACK information may be retransmitted. Alternatively, the ADAP status report may be defined as described above in the Adaptation layer device, and it may indicate whether to perform retransmission based on the ADAP status report. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may set a PDCP data recovery indicator (recoverPDCP) in the configuration information (pdcp-config) of the PDCP layer device to instruct to perform retransmission based on PDCP status reporting. The parent radio node may be configured to trigger the PDCP data recovery processing procedure and transmit the PDCP status report by the terminal or the child radio node using the above-described indicator. In addition, when performing retransmission in PDCP data recovery processing, the parent wireless node can perform selective retransmission based on PDCP status report, not successful delivery of lower layer devices (for example, RLC layer devices). have. That is, retransmission can be performed only on data indicated as data for which successful delivery is not confirmed (NACK) in the PDCP status report. Alternatively, the ADAP layer device may define ADAP status reporting and ADAP data recovery processing procedures as described above, and indicate whether to perform retransmission based on ADAP status reporting. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) sets the indicator and period or timer value to periodically send the PDCP status report so that the PDCP status report can be periodically transmitted from the PDCP layer device configuration information (pdcp-config). Can be. When receiving the above-described indicator and settings, the terminal or the child wireless node may trigger the PDCP status report according to the period or whenever the timer value expires and transmit the PDCP status report. Alternatively, the ADAP layer device may define an ADAP status report as described above, and instruct the ADAP status report to be periodically performed. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionSetup message (or RRCResume message) may set an indicator and a timer value to transmit a PDCP status report so that a PDCP status report can be transmitted from the PDCP layer device configuration information (pdcp-config). When receiving the above-described indicators and settings, the PDCP layer device of the terminal or the child wireless node triggers a timer having a timer value whenever a gap occurs in the PDCP serial number, and the PDCP serial number until the timer expires. If the gap does not fill or if data corresponding to the PDCP serial number that is assumed to be lost does not arrive, the PDCP status report is triggered when the timer expires, and the PDCP status report can be configured and transmitted. If the PDCP serial number gap is filled before the timer expires, or if data corresponding to the PDCP serial number assumed to be lost arrives, the timer can be stopped and initialized. Here, the timer may use a PDCP reordering timer, and may define a new timer having a smaller or larger value than the PDCP reordering timer. In addition, the above-described timer may also be defined and set in the ADAP layer device.

Using the newly defined RRC message or RRCConnectionSetup message (or RRCResume message), a PDCP status report prohibit timer is used to prevent triggering of frequent PDCP status reporting in the PDCP layer device configuration information (pdcp-config). Can be set. When the PDCP status reporting prohibition timer is set, the terminal or a child wireless node may trigger PDCP status reporting, configure and transmit PDCP status reporting, and trigger a PDCP status reporting prohibition timer. In addition, while the PDCP status reporting inhibit timer is running, an additional PDCP status report may be prevented from being transmitted, and the PDCP status report may be transmitted after the PDCP status reporting inhibit timer expires. In addition, the above-described timer may also be defined and set in the ADAP layer device.

Congestion level, queuing delay, hop delay between wireless nodes using a newly defined RRC message or RRCConnectionSetup message (or a separate newly defined RRC message or RRCResume message) One-hop air latency) can transmit information about a parent radio node or a child radio node, and information about each hop. In addition, the number of radio hops from the radio node receiving the newly defined RRC message or RRCConnectionSetup message to the highest radio node (IAB donor) may be indicated. In addition, the radio node receiving the number of radio hops as an RRC message may increase the number of indicated hops by 1 to inform the next child node of the number of hops.

In the newly defined RRC message or RRCConnectionSetup message (or separate newly defined RRC message or RRCResume message), the out-of-order delivery function of the NR RLC layer device is requested to be performed as an in-sequence delivery function. It may include an indicator. That is, the NR RLC layer device performs a non-order delivery function by default, but can perform a sequence delivery function as an indicator of a newly defined RRC message or RRCConnectionSetup message. Here, the order transfer function means that the RLC serial number of the RLC PDU or RLC SDU received by the RLC layer device is arranged in order to transmit data to the PDCP layer device in ascending order of the RLC serial number. According to the order transfer function, if there is an RLC serial number that is lost due to an RLC serial number gap, an RLC status report is configured and transmitted for the lost RLC serial number, requesting retransmission, and greater than the lost RLC serial number. An RLC SDU or RLC PDU having an RLC serial number is not delivered to the PDCP layer device even when received, but is stored in a buffer, and when a lost RLC serial number is received, it can be delivered to the PDCP layer device in ascending order of the RLC serial number.

The newly defined RRC message or RRCConnectionSetup message (or a separate newly defined RRC message or RRCResume message) provides security in the wireless link between the wireless node (or wireless node or terminal to which the terminal is connected) and the top-level wireless node (or wireless node). In order to strengthen, a separate PDCP layer device for a radio link for each bearer or RLC channel is set in a radio node (or radio node or terminal accessed by the terminal) and a top-level radio node (or radio node), and encryption and decryption are respectively performed. Procedures can be established and used and/or integrity protection and verification procedures can be established and enabled. Here, the default setting may be that a separate PDCP layer device for a radio link between a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level wireless node (or wireless node) is not configured for each bearer or RLC channel. have. That is, it can be used for security enhancement only when configured for each bearer or RLC channel. Alternatively, since data encryption is already performed on the PDCP layer device, it is possible to set only integrity protection and verification on a separate PDCP layer device, and remove the data rate limit for integrity protection and verification on the interface between wireless backhaul nodes, It can be set if necessary.

A terminal or a child radio node that has established an RRC connection may transmit an RRCConnetionSetupComplete message (or RRCResumeComplete message) to the parent radio node (2f-15).

The RRCConnetionSetupComplete message may include SERVICE REQUEST, which is a control message that a terminal or a child radio node requests an access and mobility management function (AMF) or an MME for bearer setup for a given service. The parent wireless node may transmit a SERVICE REQUEST message included in the RRCConnetionSetupComplete message to AMF or MME. The AMF or MME can determine whether to provide the service requested by the terminal or the child radio node.

As a result of the determination, if the terminal or the child wireless node decides to provide the requested service, the AMF or MME can send the message INITIAL CONTEXT SETUP REQUEST to the parent wireless node. The INITIAL CONTEXT SETUP REQUEST message may include QoS (Quality of Service) information to be applied when setting a Data Radio Bearer (DRB), and security-related information (eg, Security Key, Security Algorithm) to be applied to the DRB. .

The parent wireless node may exchange the SecurityModeCommand message (2f-20) and the SecurityModeComplete message (2f-25) to establish security with the terminal or child wireless node. When the security setting is completed, the parent wireless node may transmit an RRCConnectionReconfiguration message to the terminal or child wireless node (2f-20).

The parent radio node indicates whether to perform retransmission to a target parent radio node or cell for pre-configured RRC messages when the terminal or child radio node performs handover using the RRCConnectionReconfiguration message. You can set an indicator. For example, the parent radio node may instruct to perform retransmission on RRC messages transmitted within a few seconds before receiving the handover indication message, before performing the handover, or before receiving the RRC message. . In addition, the above-described indicator may be indicated for each of the RRC messages specified in advance. That is, multiple indicators may indicate whether each RRC message is retransmitted. Alternatively, the above-mentioned indication of whether to retransmit may be indicated in the form of a bitmap indicating each RRC message.

The newly defined RRC message or RRCConnectionReconfiguration message may include an indicator to perform a PDCP data recovery procedure in PDCP configuration information. In addition, the RRCConnectionReconfiguration message may include an indicator indicating whether to perform a PDCP data recovery procedure for a signaling radio bearer (SRB) or a data radio bearer (DRB) in bearer configuration information. In addition, the RRCConnectionReconfiguration message may include an indicator indicating whether to discard data remaining in the PDCP layer device for a signaling radio bearer (SRB) or a data radio bearer (DRB) in bearer configuration information.

The newly defined RRC message or RRCConnectionReconfiguration message may include an indicator indicating whether to perform cumulative retransmission or selective retransmission for the AM DRB in the bearer configuration information when performing the PDCP re-establishment procedure.

The newly defined RRC message or RRCConnectionReconfiguration message may include an indicator indicating which ARQ function to use in the child wireless node, and whether to use the hop-by-hop ARQ function using the above-described indicator or end-to-end It may be indicated whether to use the ARQ function. In addition, when setting the end-to-end ARQ function, the parent wireless node performs only the function of dividing or forwarding the received RLC layer device data or performing the ARQ function as an end in the child node. It may also indicate whether or not. In addition, the parent wireless node may indicate which ARQ function to use as the default function, and if the ARQ function is not set in the newly defined RRC message or RCConnectionReconfiguration message, hop-by-hop ARQ function or end-to as the default function -end You can decide in advance to use one of the ARQ functions. In addition, the parent radio node may indicate whether the child radio node will use the data partitioning function using the newly defined RRC message or RCConnectionReconfiguration message, and activate each function of the RLC layer devices described with reference to FIGS. 2B or 4D. Whether (or whether to use) can be indicated.

The newly defined RRC message or RRCConnectionReconfiguration message may include an indicator indicating whether to use the data concatenation function in the Adaptation layer device. In addition, the newly defined RRC message or RRCConnectionReconfiguration message may include an indicator indicating whether to set the header of the Adaptation layer device, and the parent wireless node may designate the type of the header described above. For example, the parent radio node may set which information to include in the header, such as a terminal identifier or a terminal bearer identifier, a QoS identifier, a wireless node identifier, a wireless node address, or QoS information. The parent wireless node may be configured to omit the header to reduce overhead.

The parent radio node uses the newly defined RRC message or RRCConnectionReconfiguration message to use an RLC channel to be used between the transmitting Adaptation layer device and the receiving Adaptation layer device, or to be used between the child wireless node and the parent wireless node, or to be used by the terminal and the wireless node. Can be set. Specifically, the newly defined RRC message or RRCConnectionReconfiguration message is available number of RLC channels, available RLC channel identifier or mapping information of data mapped to the RLC channel (for example, terminal identifier, terminal bearer identifier, QoS information or QoS identifier mapping Information). The RLC channel may be defined as a channel that bundles data of various terminals based on QoS information and delivers data according to QoS, and the RLC channel may also be defined as a channel that bundles data for each terminal and delivers data. .

The newly defined RRC message or RRCConnectionReconfiguration message may include an indicator indicating whether to perform retransmission based on PDCP status reporting in the configuration information (pdcp-config) of the PDCP layer device. The parent radio node may instruct to perform PDCP status reporting based retransmission using the above-described indicator of the newly defined RRC message or RRCConnectionReconfiguration message. For example, when the indicator value described above is set to 0, even if a PDCP status report is received, data corresponding to NACK information of the PDCP status report may be checked and data corresponding to the ACK information may be discarded. However, when the above-described indicator value is set to 1, upon receiving the PDCP status report, data corresponding to the ACK information of the PDCP status report may be discarded and data corresponding to the NACK information may be retransmitted. Eh may define an ADAP status report as described above in the Adaptation layer device and indicate whether to perform retransmission based on the ADAP status report. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionReconfiguration message may include a PDCP data recovery indicator (recoverPDCP) in the configuration information (pdcp-config) of the PDCP layer device to instruct to perform retransmission based on PDCP status reporting. The parent radio node may be configured to trigger the PDCP data recovery processing procedure and transmit the PDCP status report by the terminal or the child radio node using the above-described indicator. In addition, when performing retransmission in PDCP data recovery processing, the parent wireless node can perform selective retransmission based on PDCP status report, not successful delivery of lower layer devices (for example, RLC layer devices). have. That is, retransmission can be performed only on data indicated as data for which successful delivery is not confirmed (NACK) in the PDCP status report. Alternatively, the ADAP layer device may define ADAP status reporting and ADAP data recovery processing procedures as described above, and indicate whether to perform retransmission based on ADAP status reporting. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionReconfiguration message may set an indicator and a periodic or timer value to periodically transmit the PDCP status report so that the PDCP status report can be periodically transmitted from the configuration information (pdcp-config) of the PDCP layer device. When receiving the above-described indicator and settings, the terminal or the child wireless node may trigger the PDCP status report according to the period or whenever the timer value expires and transmit the PDCP status report. Alternatively, the ADAP layer device may define an ADAP status report as described above, and instruct the ADAP status report to be periodically performed. Here, the ADAP status report indicates the first lost COUNT value as the PDCP status report, and the subsequent COUNT value can be indicated by a bitmap. Alternatively, the ADAP status report may indicate the highest COUNT value received in order.

The newly defined RRC message or RRCConnectionReconfiguration message may set an indicator and a timer value to transmit a PDCP status report so that a PDCP status report can be transmitted from the PDCP layer device configuration information (pdcp-config). When receiving the above-described indicators and settings, the PDCP layer device of the terminal or the child wireless node triggers a timer having a timer value whenever a gap occurs in the PDCP serial number, and the PDCP serial number until the timer expires. If the gap does not fill or if data corresponding to the PDCP serial number that is assumed to be lost does not arrive, the PDCP status report is triggered when the timer expires, and the PDCP status report can be configured and transmitted. If the PDCP serial number gap is filled before the timer expires, or if data corresponding to the PDCP serial number assumed to be lost arrives, the timer can be stopped and initialized. Here, the timer may use a PDCP reordering timer, and may define a new timer having a smaller or larger value than the PDCP reordering timer. In addition, the above-described timer may also be defined and set in the ADAP layer device.

Using the newly defined RRC message or RRCConnectionReconfiguration message, a PDCP status report prohibit timer can be set to prevent triggering of frequent PDCP status reporting in the configuration information (pdcp-config) of the PDCP layer device. When the PDCP status reporting prohibition timer is set, the terminal or a child wireless node may trigger PDCP status reporting, configure and transmit PDCP status reporting, and trigger a PDCP status reporting prohibition timer. In addition, while the PDCP status reporting inhibit timer is running, an additional PDCP status report may be prevented from being transmitted, and the PDCP status report may be transmitted after the PDCP status reporting inhibit timer expires. In addition, the above-described timer may also be defined and set in the ADAP layer device.

Using the newly defined RRC message or RRCConnectionReconfiguration message (or a separate newly defined RRC message), congestion level, queuing delay, and one-hop between wireless nodes may be useful for a wireless node. air latency), information about a parent radio node or a child radio node, and information about each hop. In addition, the number of radio hops from the radio node receiving the newly defined RRC message or RRCConnectionSetup message to the highest radio node (IAB donor) may be indicated. In addition, the radio node receiving the number of radio hops as an RRC message may increase the number of indicated hops by 1 to inform the next child node of the number of hops.

In the newly defined RRC message or RRCConnectionReconfiguration message (or separate newly defined RRC message or RRCResume message), the out-of-order delivery function of the NR RLC layer device should be performed as an in-sequence delivery function. It may include an indicator. That is, the NR RLC layer device performs a non-order delivery function by default, but may perform a sequence delivery function as an indicator of a newly defined RRC message or RRCConnectionReconfiguration message. Here, the order transfer function means that the RLC serial number of the RLC PDU or RLC SDU received by the RLC layer device is arranged in order to transmit data to the PDCP layer device in ascending order of the RLC serial number. According to the order transfer function, if there is an RLC serial number that is lost due to an RLC serial number gap, an RLC status report is configured and transmitted for the lost RLC serial number, requesting retransmission, and greater than the lost RLC serial number. An RLC SDU or RLC PDU having an RLC serial number is not delivered to the PDCP layer device even when received, but is stored in a buffer, and when a lost RLC serial number is received, it can be delivered to the PDCP layer device in ascending order of the RLC serial number.

The newly defined RRC message or RRCConnectionReconfiguration message (or a separate newly defined RRC message or RRCResume message) provides security in the wireless link between the wireless node (or wireless node or terminal to which the terminal is connected) and the top-level wireless node (or wireless node). In order to strengthen, a separate PDCP layer device for a radio link for each bearer or RLC channel is set in a radio node (or radio node or terminal accessed by the terminal) and a top-level radio node (or radio node), and encryption and decryption are respectively performed. Procedures can be established and used, and/or integrity protection and verification procedures can be established and enabled. Here, the default setting may be that a separate PDCP layer device for a radio link between a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level wireless node (or wireless node) is not configured for each bearer or RLC channel. have. That is, it can be used for security enhancement only when configured for each bearer or RLC channel. Alternatively, since data encryption is already performed on the PDCP layer device, it is possible to set only integrity protection and verification on a separate PDCP layer device, and remove the data rate limit for integrity protection and verification on the interface between wireless backhaul nodes, It can be set if necessary.

The newly defined RRC message or RRCConnectionReconfiguration message may include DRB configuration information to be processed by user data. The terminal or the child radio node may set the DRB by applying the above-described configuration information, and transmit a newly defined RRC message or RRCConnectionReconfigurationComplete message to the parent radio node (2f-35). The terminal or the child radio node and the parent radio node that has completed the DRB setup may send an INITIAL CONTEXT SETUP COMPLETE message to the AMF or MME and complete the connection.

When all of the above-described processes are completed, the terminal or the child wireless node can transmit and receive data through the parent wireless node and the core network (2f-40). In one embodiment, the data transmission process may be largely composed of three steps: RRC connection setup, security setup, and DRB setup. In steps 2f-45, the parent radio node may transmit an RRC Connection Reconfiguration message to the terminal or the child radio node for a predetermined reason to add, change, or change settings (2f-45).

In the present disclosure, the bearer may include a signaling radio bearer (SRB) and a data radio bearer (DRB). The UM DRB means a DRB using an RLC layer device operating in the Unacknowledged Mode (UM) mode, and the AM DRB means a DRB using an RLC layer device operating in the Acknowledged Mode (AM) mode.

2G is a diagram illustrating a protocol layer device that each wireless node may have in a next generation mobile communication system supporting wireless backhaul according to an embodiment.

Referring to FIG. 2G, a protocol layer device structure of wireless nodes supporting wireless backhaul can be largely divided into two types. The two types described above can be divided according to the location of an ADAP (Adaptation) layer device. The protocol layer device structure may have a protocol layer device structure (2g-01) in which the ADAP layer device is driven under the RLC layer device, and a protocol layer device structure (2g-02) in which the ADAP layer device is driven under the RLC layer device.

In FIG. 2G, the terminal 2g-05 is a protocol layer device, and can drive both a PHY layer device, a MAC layer device, an RLC layer device, a PDCP layer device, and an SDAP layer device. Wireless nodes (for example, wireless nodes that perform a wireless backhaul function for receiving and transmitting data between a terminal and an IAB donor, Node 3 (2g-10) or Node 2 (2g-15)) are PHY layer devices, The MAC layer device, the RLC layer device, and the ADAP layer device can be driven. In addition, a top-level wireless node (for example, a top-level node supporting a wireless backhaul connected with a core network to transmit data, IAB donor or Node 1 (2g-20)) includes a PHY layer device, a MAC layer device, and an RLC layer device. , Both the PDCP layer device and the SDAP layer device can be driven. On the other hand, the top wireless node may be composed of a central unit (CU) and a distributed unit (DU) connected by wire. In an embodiment, the CU may drive the SDAP layer device and the PDCP layer device, and the DU may drive the RLC layer device, the MAC layer device, and the PHY layer device.

The ADAP layer device may perform a role of distinguishing a plurality of bearers of a plurality of terminals and mapping the RLC channel. In addition, when classifying a plurality of bearers of a plurality of terminals, the ADAP layer device can group data based on a terminal criterion or QoS and map it to one RLC channel and bundle and process the data, and one RLC channel. You can reduce the overhead by bundling the data tied to with the data concatenation function. At this time, the data concatenation function configures one or a small number of headers for a plurality of data, and indicates a header field indicating concatenated data so that each data can be distinguished, and unnecessary headers are not configured for each data. It can mean a function that can reduce overhead by preventing it. In addition, the ADAP layer device can read the PDCP serial number of the received data and calculate the COUNT value. Therefore, it is possible to request retransmission with the COUNT value for the lost data, and to report the highest COUNT value received in order for the data received so far. For example, an ADAP status report or an ADAP control PDU or RRC message may indicate the retransmission request or a well received COUNT value.

In the protocol layer structure such as 2g-01 of FIG. 2G, the wireless node 3 (2g-10) corresponds to each data bearer of the terminal 2g-05 in order to process data received from the terminal 2g-05. The same first RLC layer devices as the first RLC layer devices can be driven. In addition, the wireless node 3 (2g-10) may process data received from a plurality of RLC layer devices in the ADAP layer device and map them to a new RLC channel and corresponding second RLC layer devices. The ADAP layer device of the wireless node 3 (2g-10) may play a role of distinguishing a plurality of bearers of a plurality of terminals and mapping the RLC channel. In addition, when the ADAP layer device classifies a plurality of bearers of a plurality of terminals, data is grouped based on a terminal criterion or QoS and mapped to one RLC channel, and data can be bundled and processed by the second RLC layer devices. Can. The above-described RLC channel may be defined as a channel for transmitting data according to QoS by bundling data of various terminals based on QoS information, and also as a channel for transmitting data by bundling data for each terminal.

The above-described radio node 3 (2g-10) may perform a procedure for allocating uplink transmission resources received from the parent radio node. The wireless node 3 (2g-10) has QoS information, priority, and the amount of data that can be transmitted (for example, the amount of data allowed in this uplink transmission resource) of the aforementioned RLC channel (or second RLC layer device). , Token) or the above-described RLC channel (or the second RLC layer device) may perform a procedure for allocating uplink transmission resources according to the amount of data stored in the buffer. In addition, the wireless node 3 (2g-10) may perform data transmission to the parent wireless node for data of each RLC channel by using a split function or a concatenation function according to the distributed transmission resource.

The first RLC layer device means an RLC layer device that processes data corresponding to a bearer in the same way as the RLC layer device corresponding to each bearer of the terminal, and the second RLC layer device is a terminal, QoS in the ADAP layer device. Alternatively, it may mean an RLC layer device that processes data mapped based on mapping information set by the parent wireless node.

In the protocol layer structure such as 2g-01 of FIG. 2G, the wireless node 2 (2g-10) is the second RLC layer device corresponding to the second RLC layer devices of the child wireless node (nodes 3 and 2g-10). You can drive them and process the data for the RLC channel.

In the protocol layer structure such as 2g-01 of FIG. 2G, the highest radio node 1 (2g-20) is the second RLC layer corresponding to the second RLC layer devices of the child radio node (nodes 2 and 2g-15). You can drive the devices and process the data for the RLC channel. In addition, the ADAP layer device of the highest radio node 1 (2g-20) may serve to map the data processed for the above-described RLC channel to PDCP layer devices suitable for each bearer of each terminal. In addition, the PDCP layer device of the highest radio node corresponding to each bearer of each terminal can process the received data, deliver the data to the SDAP layer device, and process the data to deliver the data to the core network.

2ha is a diagram illustrating a bearer management and processing method of wireless nodes in a next generation mobile communication system supporting wireless backhaul according to an embodiment.

Referring to Figure 2ha, a wireless node (e.g., terminal, 2h-04) includes wireless node 3 (e.g., intermediate wireless node or IAB node, 2h-03) and wireless node 2 (e.g., wireless node) Alternatively, the IAB node, 2h-02) can transmit and receive data to and from a top-level wireless node (eg, IAB donor, 2h-01) connected to the core network.

In one embodiment, in such a wireless backhaul network, each wireless node may set a first SRB (2h-31, 2h-21, 2h-11) for establishing an RRC connection with a parent wireless node. The first SRB is connected to the PHY layer device, the MAC layer device and the RLC layer device in the intermediate wireless node, and can be directly connected to the PDCP layer device without being connected to the ADAP layer device. In addition, the first SRB can be used to send and receive RRC messages between two radio nodes connected to one radio link, and can perform separate encryption and decryption or integrity protection and integrity verification procedures in the connected PDCP layer device. have.

In addition, in one embodiment, the wireless node 3 (e.g., UE accessed IAB node, wireless node 3, 2h-03) accessed by the terminal is configured with a NAS message or an F1 interface or higher layer device for network configuration for the corresponding terminal. A second SRB (2h-34, 2h-22, 2h-11) may be set in order to transmit and receive data or a control message of an upper layer device through the highest radio node (for example, radio nodes 1 and 2h-01). have. The wireless node 3 accessed by the terminal checks the RRC message received through the first SRB, and must be delivered to the top-level wireless node or core network as a NAS message or F1 interface or data of a higher layer device or a control message of a higher layer device. Data that needs to be transmitted can be transmitted to the wireless node 2 (2h-02) through the second SRB or the first RLC bearer or the first RLC channel, and the wireless node 2 sends the data to the second SRB or The first RLC bearer or the first RLC channel may be transmitted to the highest radio node 1 again. The top radio node 1 that has received the data delivers the data to the core network, and upon receiving the response data from the core network, transmits the response data through the second SRB or the first RLC bearer or the first RLC channel to the wireless node 3 The wireless node 3 may transmit response data to the terminal through the first SRB or the second SRB. The second SRB or the first RLC bearer or the first RLC channel is configured with a PHY layer device, a MAC layer device, an RLC layer device, and an ADAP layer device in intermediate wireless nodes (for example, wireless node 2 or wireless node 3). Can be connected. That is, unlike the first SRB, the second SRB or the first RLC bearer or the first RLC channel may be mapped to the new RLC layer device through the ADAP layer device and delivered to the next wireless node.

In one embodiment, the wireless node 3 (eg, UE accessed IAB node, wireless node 3, 2h-03) accessed by the terminal generates and manages corresponding DRBs to process data received from the terminal, The corresponding DRBs (2h-32, 2h-33, 2h-23, 2h-24, 2h-13, 2h-14) may be connected to the PHY layer device, MAC layer device, RLC layer device, and ADAP layer device. Accordingly, the wireless node 3 accessed by the terminal may map data corresponding to the DRB to the next wireless node by mapping the new RLC layer device through the ADAP layer device. Here, the intermediate wireless node 2 may transmit and receive data by connecting to the PHY layer device, the MAC layer device, the RLC layer device, and the ADAP layer device to process data received through the RLC channel from the child wireless node 3.

In a method for managing and processing bearers of wireless nodes according to an embodiment, each wireless node performs a data concatenation function in an ADAP layer device for data corresponding to DRBs of a terminal, and an ADAP layer for first SRBs Since the device is not connected, the data concatenation function is not performed.

In addition, in a bearer management and processing method of wireless nodes according to an embodiment, a security key used when performing encryption and integrity protection procedures on data for first SRBs is a parent wireless node or a top-level wireless of each wireless link. It can be determined by the node. That is, 2h-31 and 2h-21 and 2h-11 can both share and use the same security key, but to enhance security, the parent wireless nodes are individually used (for example, the security key for 2h-31). The wireless node 3 determines, and the security key for 2h-21 is determined by the wireless node 2). In addition, for the second SRB, each intermediate wireless node does not process separate encryption and integrity protection, except for encryption and integrity protection applied to NAS messages. In addition, each intermediate wireless node performs encryption and integrity protection as described above for the first SRB, but does not process separate encryption and integrity protection for DRBs except for the first SRB.

In addition, in a bearer management and processing method of wireless nodes according to an embodiment, a third SRB may be defined and used. The third SRB or the second RLC bearer or the second RLC channel may be used as a control bearer for transmitting and receiving control messages between each radio node and the highest radio node. That is, a bearer for transmitting and receiving a message (for example, an RRC message or an interface message of a higher layer device) for directly controlling each wireless node by the top-level wireless node may be defined and used. For example, a third SRB can be set and a control message can be exchanged between the top wireless node 1 and a wireless node 2, and a third SRB can be set and a control message can be exchanged between the top wireless node 1 and the wireless node 3. The wireless node 2 may transmit data corresponding to the third SRB between the highest wireless node 1 and the wireless node 3. The third SRB may perform the same procedure as the first SRB, or may have the same protocol layer devices.

In the present disclosure, one wireless node (c) has both a mobile terminal (IAB-MT) and distributed unit (IAB-DU) devices. That is, it may be referred to as IAB-MT or IAB-DU depending on whether a single wireless node transmits, receives or processes a message. In addition, the BAP layer device of one wireless node may have a unique BAP address of the BAP layer device, and may have a path identifier that can be used to transmit or receive data to or from another wireless node. . In addition, one wireless node may be connected to a plurality of wireless links with other wireless nodes to receive data through a plurality of ingress links, or may transmit data through a plurality of egress links. . In addition, when a BAP layer device transmits data (for example, a BAP SDU or a BAP PDU) through each radio link, data can be transmitted by transmitting data to a lower layer device through one RLC channel among a plurality of RLC channels. have. Here, the routing configuration information of the plurality of reception links and the plurality of transmission links or the plurality of reception RLC channels and the plurality of transmission RLC channel mapping information may be set as a parent radio node or a top-level radio node as an RRC message. In addition, the BAP header may include a BAP address or a path identifier or a terminal bearer identifier.

In one embodiment, IAB-MT is not a terminal but a wireless node, but as a device of a wireless node, like a terminal, it establishes a connection with a base station or a parent (parent) wireless node (IAB node) and transmits or receives uplink or downlink data. It is a device that performs a role. That is, it is a device for performing communication between wireless nodes. IAB-MT works like a terminal, but there are actually two types of data that need to be processed. The first data is traffic for forwarding data received from the lower IAB node or terminal, and the second data is IAB and traffic such as RRC message that the wireless node itself sends to the parent IAB node to establish a wireless connection like the terminal. The node itself can be created or configured as TCP/IP layer device or application layer data as data traffic to set network configuration or basic configuration information as implementation for OAM (Operation and Management), or include control messages for F1 interface can do. Accordingly, the IAB-MT is a BAP-RLC-MAC bearer (or RLC channel) for the first data and an RRC-PDCP-RLC-MAC control bearer (or SRB) or a higher layer device-PDCP for the second data. -RLC-MAC data bearer or F1AP-BAP-RLC-MAC can be set and used.

In one embodiment, the IAB-DU is a wireless node, not a terminal, but as a device of a wireless node, establishes a connection to a terminal or a child (child) IAB node like a base station and receives or transmits uplink or downlink data. It is a device to perform. However, there is no function to generate an RRC message because there is an RRC layer device like a base station. In a wireless backhaul network environment, the RRC layer device is only in the CU of the IAB donor. After all, when the CU of the IAB donor receives the second data and generates an RRC message for the connection of the terminal or the IAB nodes, or a response message for the second data or the second data, and delivers it to the IAB-DU, the IAB-DU The RRC message or OAM data or second data is transmitted as a base station. Therefore, the IAB-DU receives the first traffic as a bearer (or RLC channel) of the receiving BAP-RLC-MAC when receiving, and allows the receiving BAP to transmit to the transmitting BAP, or transmits the second traffic or Even if received, it plays a role of transmitting traffic or receiving and transmitting a response message corresponding to the traffic. To the terminal or child IAB node, the IAB-DU looks like a base station, but actually plays a role of transferring data to a CU or receiving and transmitting data of the CU. Even if a plurality of IAB-MTs establish a connection to the IAB-DU, the IAB-DU receives the messages of each IAB-MT and delivers them to the CU and responds to the corresponding response messages as if the base station establishes a connection to a plurality of terminals. It can be transmitted to IAB-MT to establish a connection like a base station.

In a wireless backhaul network (IAB) environment described in the present disclosure, a terminal may include a general terminal, such as a Rel-16 terminal or a Rel-15 terminal, and whether or not the network uses a wireless backhaul network (IAB) function on the network side or is implemented. There is no need to know.

Figure 2hb is a wireless backhaul network (IAB, Integrated Access Backhaul) environment according to an embodiment of the present disclosure to process different data differently according to the type of data or to transmit or receive by processing data with different protocol layer devices Or it is a diagram showing a procedure for transferring, and is a diagram further embodying FIG. 2ha.

In FIG. 2HB, when a UE transmits first data or uplink data (data for service of an application layer device), procedures for processing the first data or uplink data in the wireless backhaul network are 2h-2-01 and same. The terminal configures the SDAP header when the SDAP header is set in the SDAP layer device for the first data, and if the SDAP header is not set, the SDAP header is not configured, and the data is transmitted to the PDCP layer device. The UE applies an integrity verification or encryption procedure to the data in the PDCP layer device, configures the PDCP header, and delivers the RLC layer device to configure the RLC header. The UE may transmit the first data from the MAC layer device to the wireless node 1 (2h-2-10) including the logical channel identifier or data length information corresponding to the RLC layer device. In the wireless node 1 (2h-2-01), the first data is received by the MAC layer device or the RLC layer device of the IAB-DU corresponding to the MAC layer device or RLC layer device of the terminal. The wireless node 1 (2h-2-01) processes data through a plurality of upper layer devices (such as GTP-U or UDP or IP or DSCP) to transmit the first data to the wireless backhaul network, and the BAP layer device Data to the user. Here, the BAP layer device of the IAB-MT sets a radio backhaul routing in which a transmission link having a destination address or a path identifier equal to a BAP address or a BAP path identifier corresponding to the first data (or BAP PDU or BAP SDU) is set to RRC. If it is in the information, it selects the transmission link and decides the transmission to the transmission link. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. In addition, when data is received from an upper layer device, if there is no radio backhaul RLC channel mapping configuration information for the BAP SDU receiving the uplink first data, a basic RLC channel set as an RRC message can be selected. If there is radio backhaul RLC channel mapping configuration information for the BAP SDU, the RLC channel may be selected according to the mapping information. In addition, if there is no uplink backhaul setting information or routing information, a default BAP address or a default BAP path identifier set as an RRC message is selected and a BAP PDU is transmitted to correspond to a basic RLC channel or a selected RLC channel or a basic RLC channel or a selected RLC channel. The first data can be transmitted to the wireless node 2 (2h-2-20) through the RLC layer device and the MAC layer device. The IAB-DU of the wireless node 2 (2h-2-20) may receive the first data through the MAC layer device or the RLC layer device (or RLC channel) or the BAP layer device. The IAB-DU may receive the first data (eg, BAP PDU) and identify the BAP address or BAP path identifier of the BAP header. If the BAP address of the BAP header is the BAP address of the wireless node 2 (2h-2-20), it is the data to be received and processed by the wireless node 2 (2h-2-20). Data can be transferred to the device. If the BAP address is not the BAP address of the wireless node 2 (2h-2-20), the first data (or BAP SDU) is transmitted to the transmitting part of the wireless node 2 (2h-2-20) or the BAP layer of the IAB-MT Can be delivered to the device. The BAP layer device of the IAB-MT is a BAP address or BAP path identifier corresponding to the first data (or BAP PDU or BAP SDU) or a destination address or path identifier or transmission link (or identifier) identical to the selected transmission link (or identifier). If the transmission link having) is in the radio backhaul routing configuration information set to RRC, the corresponding transmission link is selected and transmission to the corresponding transmission link is determined. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. If a transmission link for the first data is selected, a transmission RLC channel having the same value as the reception RLC channel of the reception link where the first data is received is a BAP address corresponding to the first data (or BAP PDU or BAP SDU). Alternatively, it can be confirmed in radio backhaul RLC channel mapping information set to RRC having the same destination address or path identifier or transmission link (or identifier) as the BAP path identifier or transmission link (or identifier). Thereafter, the identified transmission RLC channel for the corresponding transmission link may be selected and transmitted to the highest radio node (2h-2-30) through the RLC layer device or MAC layer device corresponding to the transmission RLC channel. The BAP layer device may receive data through the MAC layer device of the IAB-DU of the highest-level wireless node or the reception RLC channel or the reception RLC layer device. If the BAP address of the BAP header of the first data is the BAP address of the highest-level radio node (2h-2-30), the data is processed by the BAP SDU because the highest-level radio node (2h-2-30) is the data to be received and processed. And transfer the data to the upper layer device.

In FIG. 2HB, when a top-level wireless node transmits first data or uplink data (data for service of an application layer device), a procedure for processing first data or downlink data in a wireless backhaul network is 2h-2- Same as 01. Here, when the SDAP header is set in the SDAP layer device for the first data, the top-level wireless node configures the SDAP header and, if the SDAP header is not set, delivers the data to the PDCP layer device without configuring the SDAP header. do. The PDCP layer device applies integrity verification or encryption procedures to the data, configures the PDCP header, processes the data through multiple upper layer devices (such as GTP-U or UDP or IP or DSCP), and BAP of the IAB-DU Data is transmitted to the layer device. When the BAP layer device of the IAB-DU receives data from the upper layer device, the BAP address or BAP path identifier corresponding to the first data (or BAP PDU or BAP SDU) or a destination address identical to the transmission link (or identifier) or If a transmission link having a path identifier or a transmission link (or identifier) is in radio backhaul routing configuration information set to RRC, a corresponding transmission link is selected and transmission to the transmission link is determined. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. In addition, if there is no radio backhaul RLC channel mapping configuration information for the BAP SDU receiving the uplink first data, the default RLC channel set as the RRC message may be selected. If the BAP SDU has the same destination address or path identifier or transmission link (or identifier) as the BAP address or BAP path identifier or transmission link (or identifier) corresponding to the first data (or BAP PDU or BAP SDU). If there is wireless backhaul RLC channel mapping configuration information, an RLC channel may be selected according to the mapping information. In addition, if there is no uplink backhaul setting information or routing information, a default BAP address or a default BAP path identifier set as an RRC message is selected and a BAP PDU is transmitted to correspond to a basic RLC channel or a selected RLC channel or a basic RLC channel or a selected RLC channel. The first data can be transmitted to the wireless node 2 (2h-2-20) through the RLC layer device and the MAC layer device. The IAB-MT of the wireless node 2 (2h-2-20) may receive the first data through the MAC layer device or the RLC layer device (or RLC channel) or the BAP layer device. The IAB-DU may receive the first data (eg, BAP PDU) and identify the BAP address or BAP path identifier of the BAP header. If the BAP address of the BAP header is the BAP address of the wireless node 2 (2h-2-20), it is the data to be received and processed by the wireless node 2 (2h-2-20). Data can be transferred to the device. If the BAP address is not the BAP address of the wireless node 2 (2h-2-20), the first data (or BAP SDU) is transmitted to the transmitting part of the wireless node 2 (2h-2-20) or the BAP layer of the IAB-MT Can be delivered to the device. The BAP layer device of IAB-MT is configured to transmit backlinks having the same destination address or path identifier as the BAP address or BAP path identifier corresponding to the first data (or BAP PDU or BAP SDU) to the wireless backhaul routing configuration information set to RRC. If there is, select the corresponding transmission link and decide to transmit to the corresponding transmission link. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. If the transmission link for the first data is selected, the transmission RLC channel having the same value as the reception RLC channel of the reception link for which the first data is received is checked in the wireless backhaul RLC channel mapping information set to RRC and for the transmission link Select the transmission RLC channel identified above. Thereafter, it may be transmitted to the wireless node 1 (2h-2-10) through the RLC layer device or the MAC layer device corresponding to the transmission RLC channel. In the same manner as described above, the wireless node 1 may transmit downlink first data to the terminal.

In FIG. 2hb, when the terminal 2h-2-02 or the wireless node 1 (2h-2-03, 2h-2-03) transmits second data (for example, RRC message) or F1 interface message data , The procedure for processing the second data or F1 interface message data in the wireless backhaul network is the same as 2h-2-02 or 2h-2-03 or 2h-2-04. In one embodiment, the terminal or the wireless node configures the RRC message in the RRC layer device as the second data and transmits the data to the PDCP layer device. The PDCP layer device applies the integrity verification or encryption procedure to the data, configures the PDCP header and passes it to the RLC layer device to configure the RLC header, and the MAC layer device receives the logical channel identifier or data length information corresponding to the RLC layer device. In addition, the second data may be transmitted to the wireless node 1 (2h-2-10) or the wireless node 2 (2h-2-20).

In the wireless node 1 (2h-2-01) or the wireless node 2 (2h-2-20), the second data is transmitted to the MAC layer device or RLC layer device of the IAB-DU corresponding to the MAC layer device or RLC layer device of the terminal. A wireless node 1 (2h-2-01) or wireless node 2 (2h-2-01) receives a plurality of upper layer devices (GTP-U or UDP or IP or DSCP, etc.) to process the data and deliver the data to the BAP layer device. The BAP layer device of the IAB-MT is configured to transmit the back link having the same destination address or path identifier as the BAP address or BAP path identifier corresponding to the second data (or BAP PDU or BAP SDU) to the wireless backhaul routing configuration information set to RRC. If there is, select a transmission link and decide to transmit on the transmission link. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. In addition, if the BAP layer device of the IAB-MT receives data from the upper layer device, if there is no radio backhaul RLC channel mapping configuration information for the BAP SDU receiving the uplink second data, the default RLC channel set as the RRC message is selected. Can be. If there is radio backhaul RLC channel mapping configuration information for the BAP SDU, the RLC channel may be selected according to the mapping information. In addition, if there is no uplink backhaul setting information or routing information, a default BAP address or a default BAP path identifier set as an RRC message is selected and a BAP PDU is transmitted to a default RLC channel or a selected RLC channel or to the default RLC channel or selected RLC channel The second data may be transmitted to the wireless node 2 (2h-2-20) through the corresponding RLC layer device and MAC layer device. The IAB-DU of the wireless node 2 (2h-2-20) may receive the second data through the MAC layer device or RLC layer device (or RLC channel) or BAP layer device. The IAB-DU may receive the second data (eg, BAP PDU) and identify the BAP address or BAP path identifier of the BAP header. If the BAP address of the BAP header is the BAP address of the wireless node 2 (2h-2-20), it is the data to be received and processed by the wireless node 2 (2h-2-20). Can pass data. If the BAP address is not the BAP address of the wireless node 2 (2h-2-20), the second data (or BAP SDU) is transmitted to the transmitting part of the wireless node 2 (2h-2-20) or the BAP layer of the IAB-MT Can be delivered to the device. The BAP layer device of the IAB-MT is a BAP address or BAP path identifier corresponding to the second data (or BAP PDU or BAP SDU) or a destination address or path identifier or transmission link (or identifier) identical to the selected transmission link (or identifier). If the transmission link with) is in the radio backhaul routing configuration information set to RRC, the transmission link is selected and transmission to the transmission link is determined. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. If the transmission link for the second data is selected, the BAP address corresponding to the second data (or BAP PDU or BAP SDU) is the transmission RLC channel having the same value as the reception RLC channel of the reception link where the second data is received. Alternatively, it is confirmed by radio backhaul RLC channel mapping information set to RRC having the same destination address or path identifier or transmission link (or identifier) as the BAP path identifier or transmission link (or identifier). The transmission RLC channel identified above may be selected for the transmission link and transmitted to the highest radio node 2h-2-30 through the RLC layer device or MAC layer device corresponding to the transmission RLC channel. The BAP layer device may receive data through the MAC layer device of the IAB-DU of the highest-level wireless node or the reception RLC channel or the reception RLC layer device. If the BAP address of the BAP header of the second data is the BAP address of the highest wireless node (2h-2-30), the data is processed by the BAP SDU because the highest wireless node (2h-2-30) is the data to be received and processed. And transfer the data to the upper layer device.

In addition, when a message related to the F1 interface is generated in the wireless node, such as 2h-02-04, the BAP layer device of the IAB-MT of the wireless node has a BAP address or BAP corresponding to the second data (or BAP PDU or BAP SDU). If the transmission link having the same destination address or path identifier as the path identifier is in the radio backhaul routing configuration information set to RRC, the corresponding transmission link is selected and transmission to the corresponding transmission link is determined. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. In addition, if the BAP layer device of the IAB-MT receives data from the upper layer device, if there is no radio backhaul RLC channel mapping configuration information for the BAP SDU receiving the F1 interface-related message, it can select the default RLC channel set as the RRC message. If there is radio backhaul RLC channel mapping configuration information for the BAP SDU or F1 interface related message, the RLC channel may be selected according to the mapping information. In addition, if there is no radio backhaul setting information or routing information, a default BAP address or a default BAP path identifier set as an RRC message is selected, and a BAP PDU is transmitted to correspond to a default RLC channel or a selected RLC channel or a default RLC channel or a selected RLC channel. The RLC layer device and the MAC layer device may transmit an F1 interface related message to the wireless node 2 (2h-2-20).

The IAB-DU of the wireless node 2 (2h-2-20) may receive an F1 interface related message through a MAC layer device or an RLC layer device (or RLC channel) or a BAP layer device. The IAB-DU may receive an F1 interface-related message (eg, BAP PDU) and check the BAP address or BAP path identifier of the BAP header. If the BAP address of the BAP header is the BAP address of the wireless node 2 (2h-2-20), the data is to be received and processed by the wireless node 2 (2h-2-20). Data can be transferred to a layered device. If the BAP address is not the BAP address of the wireless node 2 (2h-2-20), the F1 interface related message (or BAP SDU) is transmitted to the wireless node 2 (2h-2-20) transmission part or IAB-MT's BAP layer Can be delivered to the device. Here, the BAP layer device of the IAB-MT is a BAP address or BAP path identifier corresponding to an F1 interface related message (or BAP PDU or BAP SDU), or a destination address or path identifier or transmission link (same as the selected transmission link (or identifier)) Or, if the transmission link having the identifier) is in the radio backhaul routing configuration information set to RRC, select the transmission link and determine transmission to the transmission link. If there is no transmission link having the same information in the wireless backhaul routing configuration information, an arbitrary transmission link may be selected. If a transmission link for an F1 interface-related message is selected, a BAP address corresponding to an F1 interface-related message (or BAP PDU or BAP SDU) for an outgoing RLC channel having the same value as the receiving RLC channel of the receiving link for which the F1 interface-related message was received. Alternatively, it can be confirmed in radio backhaul RLC channel mapping information set to RRC having the same destination address or path identifier or transmission link (or identifier) as the BAP path identifier or transmission link (or identifier). Thereafter, the identified transmission RLC channel for the transmission link may be selected and transmitted to the highest radio node 2h-2-30 through the RLC layer device or MAC layer device corresponding to the transmission RLC channel. Here, the BAP layer device may receive data through the MAC layer device of the IAB-DU of the highest radio node or the reception RLC channel or the reception RLC layer device. If the BAP address of the BAP header of the F1 interface-related message is the BAP address of the top-level wireless node (2h-2-30), the data is processed by the BAP SDU because the top-level wireless node (2h-2-30) is the data that must be received and processed And transfer the data to the upper layer device.

The following describes a security enhancement method that can detect data errors that may occur when data is transmitted between wireless nodes in a next-generation mobile communication system that supports wireless backhaul and prevents unexpected attacks.

2i is a security in a wireless link or a wireless section (for example, a wireless link between a terminal and a wireless node in a wireless backhaul network or between a terminal and a top-level node or a wireless node connected to a terminal and a top-level wireless node) according to an embodiment. It is a diagram showing how to strengthen the.

Referring to Figure 2i, 2i-01 is a wireless interval (for example, a wireless link between a terminal and a wireless node in a wireless backhaul network or between a terminal and a top-level node or a wireless node connected to a terminal and a top-level wireless node) It shows a first embodiment that can enhance security when transmitting data across nodes or across multiple radio hops.

In FIG. 2i, the F1 interface may be defined as a radio link between a top-level wireless node and an end of a wireless node accessed by a terminal (eg, an interface between 2i-11 and 2i-13 or an interface between 2i-21 and 2i-23). , F1 interface may include a plurality of wireless nodes or a plurality of wireless links.

2i-01 is a wireless section (e.g., a wireless link between a terminal and a wireless node in a wireless backhaul network or between a terminal and a top-level node or between a wireless node and a top-level wireless node to which the terminal is connected) across multiple wireless nodes or multiple wireless This is a first embodiment capable of enhancing security when transmitting data over a hop. In the first embodiment, wireless nodes (terminals or wireless nodes or top-level wireless nodes) set up separate upper layer devices (for example, IPsec layer devices) and encrypt and decrypt or protect and verify integrity and integrity in a separate upper layer device. You can enhance security by setting and executing. That is, in order to enhance security for the F1 interface 2i-10 between the top node 2i-13 and the wireless node 2i-11 accessed by the terminal, the top node or wireless node is a separate upper layer device (for example, For example, each IPsec layer device) may be set, encryption may be performed when data is transmitted, or integrity protection may be performed and data may be transmitted, and a wireless node or a top-level node may decrypt the data at a separate upper layer device when receiving the data. Alternatively, integrity verification may be performed to prevent unexpected attacks or to verify data errors or data integrity.

Here, in order to enhance security in a wireless link between a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level wireless node (or wireless node), a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level In a radio node (or radio node), a separate upper layer device for the radio link may be set for each bearer or RLC channel, and an encryption and decryption procedure may be set, or an integrity protection and verification procedure may be set and used. Therefore, in one radio node, a separate upper layer device may be configured for a certain bearer or a certain RLC channel, and encryption and decryption procedures may be performed or integrity protection and verification procedures may be performed, and another bearer or another RLC channel may be used. For this, the encryption and decryption procedures may be separately performed or the integrity protection and verification procedures may not be performed separately without setting up a separate upper layer device.

Referring to Figure 2i, 2i-02 is a radio in a wireless section (for example, a wireless link between a terminal and a wireless node in a wireless backhaul network or between a terminal and a top-level node or a wireless node connected to a terminal and a top-level wireless node) It represents a second embodiment that can enhance security when transmitting data across nodes or across multiple radio hops.

In the second embodiment, wireless nodes (terminals or wireless nodes or top-level wireless nodes) set up separate upper layer devices (eg, separate PDCP layer devices, 2i-27, 2i-28), and separate upper layers. The devices 2i-27 and 2i-28 may establish and perform encryption and decryption or integrity protection and verification procedures to enhance security. That is, in order to enhance security for the F1 interface 2i-20 between the top node 2i-23 and the wireless node 2i-21 accessed by the terminal, the top node or the wireless node is a separate upper layer device (for example, For example, a separate PDCP layer device, 2i-27, 2i-28) may be set, encryption may be performed when data is transmitted, or integrity protection may be performed and data may be transmitted, and the wireless node or the top node receives the data When performing a decryption or integrity verification on a separate upper layer device, it is possible to protect against unexpected attacks or data errors or data integrity.

Here, in order to enhance security in a wireless link between a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level wireless node (or wireless node), a wireless node (or a wireless node or terminal accessed by a terminal) and a top-level In a radio node (or radio node), a separate upper layer device (2i-27, 2i-28) for the radio link is set for each bearer or RLC channel, and encryption and decryption procedures are set or integrity protection and verification procedures are set. Can be set and enabled. Accordingly, a separate upper layer device (2i-27, 2i-28) may be set for a certain bearer or a certain RLC channel in one wireless node, and encryption and decryption procedures may be performed or integrity protection and verification procedures may be performed. For another bearer or another RLC channel, an encryption and decryption procedure may not be separately performed without setting a separate upper layer device, or an integrity protection and verification procedure may not be separately performed.

In the second embodiment, the wireless node (the wireless node connected to the terminal or the terminal or the most advanced wireless node) is a PDCP layer device (2i-27, 2i-28) above the ADAP layer device or other higher layer device for data bearers (DRBs). ) Is not generally set, but separate PDCP layer devices (2i-27, 2i-28) for specific data bearers to perform encryption or integrity protection to enhance security of the F1 interface are used as ADAP layer devices or other higher level. It can be set on a layered device and can perform encryption or integrity protection procedures. The second embodiment can also be applied to control bearers (SRBs).

FIG. 2J sets a separate upper layer device (for example, a second PDCP layer device) to protect security of an F1 interface in a wireless section in a wireless backhaul network structure according to the embodiment described in FIG. 2G and protects integrity and It is a figure for specifically describing a 2-1 embodiment performing a verification procedure.

In FIG. 2J, the next generation mobile communication base station of the wireless backhaul network may be composed of a top-level wireless node (2j-04) and a plurality of intermediate wireless nodes (2j-02, 2j-03), and a top-level wireless node (2j-04). In order to process data for a terminal connected to a network, the MAC layer device or the RLC layer device or the PDCP layer device may perform data processing for each bearer. In addition, the intermediate wireless nodes may perform data processing by bundling data transmitted from a plurality of bearers for a plurality of terminals into an RLC channel for each terminal or for each QoS or based on a specific condition. The procedure for classifying RLC channels and classifying data may be performed in the ADAP layer device.

When transmitting downlink (or uplink) data in FIG. 2j, the highest node (or terminal) is upper layer data corresponding to the first data bearer in the first PDCP layer devices 2j-05 and 2j-10. For the encryption procedure or integrity protection procedure, data can be transferred to lower layers to perform transmission. When integrity protection is set by the RRC message in the first PDCP layer devices 2j-05 and 2j-10, as shown in FIG. 2f, data rate may be limited. Therefore, in the general case, integrity protection may not be set in the first PDCP layer device. When receiving the data, the receiving first PDCP layer device 2j-05 may perform decryption and perform integrity verification when integrity protection is set.

In FIG. 2J, the top node 2j-04 and the wireless node 2j are used to enhance security of the F1 interface 2j-100, which is a wireless link between the top node 2j-04 and the wireless node 2j-02 accessed by the terminal. -02) may set the second PDCP layer devices 2j-15 and 2j-20 for each bearer or for each RLC channel. In addition, integrity protection may be set and used in the second PDCP layer device. When integrity protection is set in the second PDCP layer device 2j-20, it may be characterized in that the data rate is not limited, and the integrity protection is the data received from the upper layer and the second PDCP layer device 2j. Integrity protection is performed and calculated on the second PDCP header generated in -20), and MAC-I having a predetermined size (for example, 4 bytes) is attached to the lower layer device and transmitted to the lower layer device to perform transmission. It can be characterized by.

The receiving second PDCP layer device 2j-15 receiving the data may perform decryption and perform integrity verification when integrity protection is set. When performing the integrity verification, integrity calculation is performed and the generated X-MAC is compared with the MAC-I value encountered after the received data to perform integrity verification. If the wireless node 2j-02 succeeds in integrity verification, the header and MAC-I are removed and the received data is transmitted to a higher layer device. If the wireless node 2j-02 fails to verify the integrity, the received data can be discarded. And, if the data is discarded due to the integrity verification failure, the wireless node 2j-02 is the top wireless node or the parent node because data must not be lost from the F1 interface 2j-100 even before the data is transmitted to the terminal. Can request retransmission of data. Data retransmission request indicates lost data through RRC message or new defined PDCP status report or new defined PDCP control PDU or new indicator of PDCP status report or new indicator in PDCP header or PDCP data recovery request or PDCP re-establishment procedure request And request retransmission. When the retransmission is requested, the second PDCP layer device 2j-20 may perform retransmission on data corresponding to the second PDCP serial number indicated as lost.

According to the 2-1 embodiment, a wireless node (IAB node) may configure a plurality of different types of bearer or RLC channels and efficiently transmit and receive and transmit data. In addition, among the following bearer or RLC channels, a plurality of different bearer or RLC channels may be set and used simultaneously or together.

-1st bearer or 1st RLC channel: The 1st bearer or 1st RLC channel is a control message of upper layer devices between a wireless node (IAB node) and a top-level wireless node (IAB donor) in a wireless node (eg For example, it may be set as a channel for sending and receiving application layer (AP) messages. In addition, in order to process data transmitted and received on the first bearer or the first RLC channel, data processing may be performed by setting upper layer devices, ADAP layer devices, and RLC layer devices. If fixed, data processing can be performed without setting the ADAP layer device.

-2 nd bearer or 2nd RLC channel: 2 nd bearer or 2nd RLC channel is a control message of upper layer devices between a wireless node (IAB node) and a top-level wireless node (IAB donor) in a wireless node (eg For example, an application layer (AP) message) may be set as a channel for sending and receiving. In addition, in order to process data transmitted and received in the second bearer or the second RLC channel, data processing may be performed by setting upper layer devices, ADAP layer devices, and RLC layer devices. If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device. In addition, in order to enhance security for control messages (eg, F1 interface) of upper layer devices between the wireless node (IAB node) and the highest wireless node (IAB donor), a separate method for applying the 2-1 embodiment The PDCP layer device may be additionally set to a higher level, and encryption and decryption or integrity protection and verification procedures may be performed. If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device.

-Third Bearer or Third RLC Channel: The third bearer or third RLC channel is for the wireless node to transmit data of the parent wireless node or data of the highest wireless node or data of the terminal to the next wireless node. Can be set and used. Therefore, the third bearer or the third RLC channel can perform data processing by setting the ADAP layer device and the RLC layer device to process data for delivery to the next wireless node. In addition, since the third bearer or the third RLC channel is for the purpose of data transmission, the RRC layer device or the PDCP layer device may not be set in the third bearer or the third RLC channel. . If the security enhancement is to be performed on special delivery data in the third bearer or the third RLC channel, the above-described embodiment 2-1 can be applied.

-4th bearer or 4th RLC channel: The 4th bearer or 4th RLC channel is a control message to the parent wireless node (or top-level wireless node) in order for the wireless node to establish or connect to the network. For example, it may be configured and used for the purpose of transmitting and receiving RRC messages). Therefore, the fourth bearer or the fourth RLC channel can perform data processing by setting the RRC layer device, the PDCP layer device, the ADAP layer device, and the RLC layer device to process data for establishing a connection with the network. . In addition, since the purpose is to transmit and receive control messages for which security is important, the RRC layer device and the PDCP layer device can be set to the fourth bearer or the fourth RLC channel. . If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device.

As described above, according to an embodiment, in a wireless backhaul network, wireless nodes access each other to efficiently perform wireless network access, wireless data transmission, and operation of a wireless network (for example, a wireless backhaul network topology change). Other bearer or RLC channels can be configured and operated. The configured plurality of RLC channels or bearers is configured by a combination of different layer devices so that data processing can be effectively performed for each purpose. In addition, in order to enhance security, each of the 2-1 embodiments may be set in each bearer or RLC channels.

In addition, when transmitting data, the wireless node distinguishes the data by a logical channel identifier (for example, an upper layer control message with the highest wireless node or data to be delivered to the next wireless node or RRC message for network connection access). Therefore, it can be transmitted by mapping or classifying differently to each established bearer or RLC channel.

In addition, when receiving data from the MAC layer device, the wireless node distinguishes data by a logical channel identifier (for example, an upper layer control message with the highest wireless node or data to be delivered to the next wireless node or RRC for network connection access) By distinguishing messages, etc.), data can be delivered to a higher layer device by mapping or classifying each bearer or RLC channel differently.

In one embodiment, a top-level radio node or a parent radio node sets a radio node with different layer devices in different bearers, as described in FIG. 2F, a bearer identifier or a logical channel identifier or RLC in bearer configuration information of an RRC message Map channel identifier or QoS flow information together with RRC layer device configuration information or PDCP layer device information or ADAP layer device information or RLC layer device information or MAC layer device information or SDAP layer device information, or indicate whether each layer device is set or not. Therefore, it is possible to instruct different layer devices to be set for each bearer.

In addition, in one embodiment, when trying to configure and use a separate PDCP layer device that enhances the security of the F1 interface, the wireless node uses one of the following methods for setting the security key to be used in the separate PDCP layer device. By applying and deriving a security key, it can be applied and used in the integrity protection and verification algorithm or encryption and decryption algorithm of a new PDCP layer device that is separately set.

-Method 1: If a separate PDCP layer device needs to be configured in a specific bearer or RLC channel for enhanced security, the wireless node and the parent wireless node or the wireless node and the top-level wireless node separately have encryption setting procedures to establish a newly defined encryption key. Triggering, and receiving a new security key from the top-level wireless node or the parent wireless node, which can be applied and used in the integrity protection and verification algorithm or encryption and decryption algorithm of the PDCP layer device. Accordingly, a separate security key different from the security key established by the wireless node can be used. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using a different security key from the fourth bearer.

-Method 2: If a separate PDCP layer device needs to be configured in a specific bearer or RLC channel for security enhancement, the encryption key established when the wireless node establishes a connection with the top-level wireless node or the parent wireless node can be reused. That is, it is possible to apply and use the integrity protection and verification algorithm or encryption and decryption algorithm of the PDCP layer device using the security key already set in the wireless node. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using the same security key as the fourth bearer.

-Method 3: If a separate PDCP layer device needs to be set up in a specific bearer or RLC channel for enhanced security, the encryption key established when the wireless node establishes a connection with the top-level wireless node or the parent wireless node is replaced with a new PDCP layer device. It can be reused to derive a security key. For example, when deriving a security key to be used for a new PDCP layer device, the PDCP layer is derived by deriving a new password different from the existing password by combining a previously established encryption key with a security indicator for a newly defined separate PDCP layer device. It can be applied and used in the device's integrity protection and verification algorithm or encryption and decryption algorithm. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using a different security key from the fourth bearer.

FIG. 2K illustrates a separate upper layer device (for example, a second PDCP layer device) for encryption and decryption for security enhancement of an F1 interface in a wireless section in a wireless backhaul network structure according to the embodiment described with reference to FIG. 2G. It is a figure specifically explaining the 2-2 embodiment for performing the procedure.

Referring to FIG. 2K, a next-generation mobile communication base station of a wireless backhaul network may be composed of a top-level wireless node (2k-04) and a plurality of intermediate wireless nodes (2k-02, 2k-03), and a top-level wireless node (2k) -04) may perform data processing in a MAC layer device or an RLC layer device or a PDCP layer device for each bearer for data processing for a terminal connected to a network. In addition, the intermediate wireless nodes may perform data processing by bundling data transmitted from a plurality of bearers for a plurality of terminals into an RLC channel for each terminal or for each QoS or based on a specific condition. The procedure for classifying RLC channels and classifying data may be performed in the ADAP layer device.

When transmitting downlink (or uplink) data in FIG. 2K, the highest node (or terminal) is upper layer data corresponding to the first data bearer in the first PDCP layer device (2k-05, 2k-10). For the encryption procedure or integrity protection procedure, data can be transferred to lower layers to perform transmission. When integrity protection is set by an RRC message as shown in FIG. 2F in the first PDCP layer devices 2k-05 and 2k-10, data rate may be limited. Therefore, in the general case, integrity protection may not be set in the first PDCP layer device. When receiving the data, the receiving first PDCP layer device 2k-05 may perform decryption and, if integrity protection is set, perform integrity verification.

In FIG. 2K, the top node (2k-04) and the wireless node (2k) for security enhancement of the F1 interface (2k-100), which is a wireless link between the top node (2k-04) and the wireless node (2k-02) accessed by the terminal. -02) may set the second PDCP layer device (2k-15, 2k-20) for each bearer or for each RLC channel. In addition, an encryption and decryption procedure may be set and used in the second PDCP layer device. When the encryption procedure is set in the second PDCP layer device 2k-20, the second PDCP layer device may perform encryption on data received from the upper layer. Here, when performing the encryption procedure, one of the following methods can be applied.

-1st encryption method (2k-31): In the next generation mobile communication system, encryption is not allowed for the SDAP header (2k-40) of the SDAP layer device. However, the first encryption method is characterized in that the SDAP header 2k-40 is encrypted when a second PDCP layer device, which is a separate PDCP layer device, is set to enhance security of the F1 interface 2k-100. . That is, the transmitting second PDCP layer device 2k-20 may encrypt all data (including the SDAP header) received from the upper layer and transmit data to the lower layer to perform transmission. The second PDCP layer device 2k-15 receiving the corresponding data may remove the second PDCP header from the received data, perform a decoding procedure on the remaining part, and transfer the data to the upper layer. That is, in the 2-2 embodiment, the first encryption method for enhancing security may have the following characteristics when applied in the PDCP layer device.

● If the SDAP layer device is set directly above the currently set PDCP layer device, when the PDCP layer device performs encryption, the SDAP header generated by the SDAP layer device for data received from the upper layer device (SDAP layer device) Except for the encryption can be performed on the data (for example, PDCP SDU). In addition, the PDCP layer device may perform decoding on data excluding the SDAP header from data received from the lower layer when performing decoding (in the case of a PDCP layer device set in a central unit (CU) of a terminal or IAB donor) ).

● If the SDAP layer device is not set directly above the currently set PDCP layer device (for example, when another layer is set between the SDAP layer device and the currently set PDCP layer device), the SDAP header is received from the upper layer. Even if it is included in the middle of the data, encryption can be performed on data (eg, PDCP SDU) including the SDAP header without excluding the SDAP header. In addition, the PDCP layer device may perform decoding on data including the SDAP header without excluding the SDAP header from the data received from the lower layer when decoding is performed (in the distributed unit (DU) of the IAB node or IAB donor). For PDCP layer devices configured to enhance the security of the F1 interface).

● In another method, the PDCP layer device performs encryption except for the SDAP header only when the SDAP header is included at the beginning of the data received from the upper layer, and the SDAP header is included at the beginning of the data received from the lower layer. Decoding can be performed only when there is no SDAP header. In addition, the PDCP layer device can perform encryption by including the SDAP header when there is no SDAP header at the beginning of the data received from the upper layer (for example, the SDAP header is included in the middle or non-front position). In addition, if there is no SDAP header at the beginning of the data received from the lower layer (for example, the SDAP header is included in a position other than the middle or the front), decoding may be performed by including the SDAP header.

-Second encryption method (2k-32): In the next generation mobile communication system, encryption is not allowed for the SDAP header (2k-40) of the SDAP layer device. Therefore, the second encryption method is characterized in that the SDAP header 2k-40 is not encrypted when the second PDCP layer device, which is a separate PDCP layer device, is set for security enhancement of the F1 interface 2k-100. do. That is, when transmitting the second PDCP layer device 2k-20, when performing encryption on all data (including the SDAP header) received from the upper layer, performs an encryption procedure on the data and the header portion except the SDAP header and lower Data can be transferred to a layer to perform transmission. The second PDCP layer device 2k-15 receiving the corresponding data removes the second PDCP header from the received data, performs a decoding procedure on the remaining header parts and data parts except the SDAP header, and transmits the data to the upper layer. Can pass. Since the second PDCP layer device in the highest wireless node can know the size of the first PDCP header of the first PDCP layer device, it is possible to distinguish the SDAP header and perform encryption. In addition, the header of other higher layer devices can know the size of the header because there is a length indicator for it. In the first PDCP header, there is no indicator for the size of the PDCP header, and the length of the PDCP serial number may be determined to be 2 bytes or 3 bytes, for example. Therefore, the size of the header of the first PDCP layer device is not known in the wireless node 2k-02 accessed by the terminal to which the first PDCP layer device has not been set. Therefore, the SDAP header is distinguished and the SDAP header The decoding procedure cannot be performed on the remaining header portion and data portion except. Accordingly, the top-level radio node indicates to the radio node 2k-02 the length of the first PDCP serial number or the size of the first PDCP header of the first PDCP layer device for each bearer or RLC channel of each terminal in an RRC message. You have to do it. Alternatively, an indicator may be defined in the SDAP header or the first PDCP header or the second PDCP header or other upper layer device header to indicate the size of the second PDCP header in 2 bytes or 3 bytes, for example. have.

-Third encryption method (2k-33): In the next generation mobile communication system, encryption is not allowed for the SDAP header (2k-40) of the SDAP layer device. Therefore, the second encryption method is characterized in that the SDAP header 2k-40 is not encrypted when the second PDCP layer device, which is a separate PDCP layer device, is set for security enhancement of the F1 interface 2k-100. It is characterized by encrypting only the header of the upper layer device. That is, when transmitting the second PDCP layer device 2k-20, when performing encryption on the entire data (including the SDAP header) received from the upper layer, the upper layer header excluding the SDAP header and the data attached after the SDAP header. The encryption procedure is performed only on the part and data is transmitted to a lower layer so that processing complexity due to encryption can be reduced (data already attached to the SDAP header is already encrypted in the first PDCP layer device). The second PDCP layer device 2k-15 receiving the corresponding data removes the second PDCP header from the received data and decodes the remaining upper layer device headers except the SDAP header and the data attached after the SDAP header. You can carry out the procedure and pass the data to the upper layers. Since the second PDCP layer device in the highest wireless node can know the size of the first PDCP header of the first PDCP layer device, it is possible to distinguish the SDAP header and perform encryption. In addition, the header of other higher layer devices can know the size of the header because there is a length indicator for it. In the first PDCP header, there is no indicator for the size of the PDCP header, and the length of the PDCP serial number may be determined to be 2 bytes or 3 bytes, for example. Therefore, the size of the header of the first PDCP layer device is not known in the wireless node 2k-02 accessed by the terminal to which the first PDCP layer device has not been set. Therefore, the SDAP header is distinguished and the SDAP header The decoding procedure cannot be performed on the upper layer device headers except the data concatenated after and the SDAP header. Accordingly, the top-level radio node indicates to the radio node 2k-02 the length of the first PDCP serial number or the size of the first PDCP header of the first PDCP layer device for each bearer or RLC channel of each terminal in an RRC message. You have to do it. Alternatively, an indicator may be defined in the SDAP header or the first PDCP header or the second PDCP header or other upper layer device header to indicate the size of the second PDCP header, for example, 2 bytes or 3 bytes. have.

Although the encryption and decryption procedure of the second PDCP layer device has been described in the embodiment 2-2, the second PDCP layer device performs encryption once more because the first PDCP layer device has already performed encryption on the data. Even so, security enhancements can mainly affect only the upper layer headers. Accordingly, as a method for reducing the data processing burden due to the encryption and decryption procedure, only the integrity protection and verification procedure can be set in the second PDCP layer device that is separately set to enhance the security of the F1 interface.

The security enhancement methods of the F1 interface according to an embodiment may be extended and applied as a method for enhancing the security of a radio link between a terminal and a top-level wireless node or a terminal and a wireless node.

According to the 2-2 embodiment, a wireless node (IAB node) may configure multiple bearer or RLC channels of different types and efficiently transmit/receive and transmit data. In addition, among the following bearer or RLC channels, a plurality of different bearer or RLC channels may be set and used simultaneously or together.

-1st bearer or 1st RLC channel: The 1st bearer or 1st RLC channel is a control message of upper layer devices between a wireless node (IAB node) and a top-level wireless node (IAB donor) in a wireless node (eg For example, an application layer (AP) message) may be set as a channel for sending and receiving. In addition, in order to process data transmitted and received on the first bearer or the first RLC channel, data processing may be performed by setting upper layer devices, ADAP layer devices, and RLC layer devices. If a bearer or RLC channel is designated or fixed, data processing can be performed without setting an ADAP layer device.

-2 nd bearer or 2nd RLC channel: 2 nd bearer or 2nd RLC channel is a control message of upper layer devices between a wireless node (IAB node) and a top-level wireless node (IAB donor) in a wireless node (eg For example, an application layer (AP) message) may be set as a channel for sending and receiving. In addition, in order to process data transmitted and received in the second bearer or the second RLC channel, data processing may be performed by setting upper layer devices, ADAP layer devices, and RLC layer devices. If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device. In addition, a separate PDCP for applying the 2-2 embodiment to strengthen security for control messages of the upper layer devices (for example, F1 interface) between the wireless node (IAB node) and the highest wireless node (IAB donor). The layered device may be further set and the encryption and decryption or integrity protection and verification procedures may be performed. If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device.

-Third Bearer or Third RLC Channel: The third bearer or third RLC channel is for the wireless node to transmit data of the parent wireless node or data of the highest wireless node or data of the terminal to the next wireless node. Can be set and used. Therefore, the third bearer or the third RLC channel can perform data processing by setting the ADAP layer device and the RLC layer device to process data for delivery to the next wireless node. In addition, since the third bearer or the third RLC channel is for the purpose of data transmission, the RRC layer device or the PDCP layer device may not be set in the third bearer or the third RLC channel. If the security enhancement is to be performed on special delivery data in the third bearer or the third RLC channel, the above-described embodiment 2-2 can be applied.

-4th bearer or 4th RLC channel: The 4th bearer or 4th RLC channel is a control message to the parent wireless node (or top-level wireless node) in order for the wireless node to establish or connect to the network. For example, it may be configured and used for the purpose of transmitting and receiving RRC messages). Therefore, the fourth bearer or the fourth RLC channel can perform data processing by setting the RRC layer device, the PDCP layer device, the ADAP layer device, and the RLC layer device to process data for establishing a connection with the network. . In addition, since the purpose is to transmit and receive control messages for which security is important, the RRC layer device and the PDCP layer device can be set to the fourth bearer or the fourth RLC channel. If a bearer or RLC channel is specified or fixed, data processing can be performed without setting an ADAP layer device.

As described above, according to an embodiment, in a wireless backhaul network, wireless nodes access each other to efficiently perform wireless network access, wireless data transmission, and operation of a wireless network (for example, a wireless backhaul network topology change). Other bearer or RLC channels can be configured and operated. The configured plurality of RLC channels or bearers are configured with combinations of different layer devices to effectively perform data processing for each purpose. In addition, in order to enhance security, embodiments 2-2 may be set in each bearer or RLC channel paths.

In addition, the wireless node distinguishes data by a logical channel identifier when transmitting data (for example, distinguishes upper layer control messages with the highest wireless node or data to be delivered to the next wireless node or RRC message for network connection access). Each set bearer or RLC channel may be differently mapped or classified and transmitted.

In addition, when receiving data from the MAC layer device, the wireless node distinguishes data by a logical channel identifier (for example, an upper layer control message with the highest wireless node or data to be delivered to the next wireless node or RRC message for network connection access) Differentiating, etc.) data can be delivered to a higher layer device by mapping or classifying each bearer or RLC channel differently.

In one embodiment, a top-level radio node or a parent radio node sets a radio node with different layer devices in different bearers, as described in FIG. 2F, a bearer identifier or a logical channel identifier or RLC in bearer configuration information of an RRC message Map channel identifier or QoS flow information together with RRC layer device configuration information or PDCP layer device information or ADAP layer device information or RLC layer device information or MAC layer device information or SDAP layer device information, or indicate whether each layer device is set or not. Therefore, it is possible to instruct different layer devices to be set for each bearer.

In addition, in one embodiment, when trying to configure and use a separate PDCP layer device that enhances the security of the F1 interface, the wireless node uses one of the following methods for setting the security key to be used in the separate PDCP layer device. By applying and deriving a security key, it can be applied and used in the integrity protection and verification algorithm or encryption and decryption algorithm of a new PDCP layer device that is separately set.

-Method 1: If a separate PDCP layer device needs to be configured in a specific bearer or RLC channel for enhanced security, the wireless node and the parent wireless node or the wireless node and the top-level wireless node separately have encryption setting procedures to establish a newly defined encryption key. Triggering, and receiving a new security key from the top-level wireless node or the parent wireless node, which can be applied and used in the integrity protection and verification algorithm or encryption and decryption algorithm of the PDCP layer device. Accordingly, a separate security key different from the security key established by the wireless node can be used. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using a different security key from the fourth bearer.

-Method 2: If a separate PDCP layer device needs to be configured in a specific bearer or RLC channel for security enhancement, the encryption key established when the wireless node establishes a connection with the top-level wireless node or the parent wireless node can be reused. That is, it is possible to apply and use the integrity protection and verification algorithm or encryption and decryption algorithm of the PDCP layer device using the security key already set in the wireless node. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using the same security key as the fourth bearer.

-Method 3: If a separate PDCP layer device needs to be set up in a specific bearer or RLC channel for enhanced security, the encryption key established when the wireless node establishes a connection with the top-level wireless node or the parent wireless node is replaced with a new PDCP layer device. It can be reused to derive a security key. For example, when deriving a security key to be used for a new PDCP layer device, the PDCP layer is derived by deriving a new password different from the existing password by combining a previously established encryption key with a security indicator for a newly defined separate PDCP layer device. It can be applied and used in the device's integrity protection and verification algorithm or encryption and decryption algorithm. For example, the second bearer described above may perform encryption and decryption or integrity protection or verification using a different security key from the fourth bearer.

In the present disclosure, embodiments and methods for enhancing security by setting a separate second PDCP layer device for each bearer or RLC channel set in a wireless node to enhance security of data transmitted between wireless nodes have been described. The embodiments and methods described in the present disclosure may be extended to further enhance security between wireless nodes.

When routing data between wireless nodes, wireless nodes determine routing through an ADAP layer device. In addition, the ADAP header of the ADAP layer device may include a terminal bearer identifier or a terminal identifier or a routing identifier or a radio node address or QoS information. Therefore, if the information is changed by a hacker, routing problems may occur when data is transmitted between wireless nodes, and data may not be properly transmitted to a terminal corresponding to a destination address of data, and data may be lost. . Therefore, in order to solve this security problem, the embodiments described in the present disclosure may be extended and applied as follows.

For example, the parent radio node or the top radio node sets a separate PDCP layer device under the ADAP layer device for each bearer or RLC channel set in the child radio node as an RRC message, and then adds an ADAP header or data (eg, ADAP SDU). Can be encrypted and decrypted, or integrity protection or integrity verification can be performed. That is, when data is transferred from the ADAP layer device to the lower layer device, the second PDCP layer device set at the lower level encrypts the ADAP header or data (eg, ADAP SDU) of the upper layer device, the ADAP layer device, or Integrity protection can be performed and transmitted to lower layers.

In addition, a separate second PDCP layer device set under the ADAP layer device may perform decoding and integrity verification procedures on data including the ADAP header when receiving data from the lower layer.

Here, the parent radio node or the top radio node selectively activates (or sets) or disables (or does not set) encryption and decryption functions or integrity protection and verification functions of the second PDCP layer device, respectively, as RRC messages. ) To control the processing complexity of the wireless node.

As another method, since the encryption and decryption procedure can greatly increase the data processing complexity of the wireless node, the parent wireless node or the top wireless node is a separate second for each bearer or RLC channel set in the child wireless node as an RRC message. By setting the light PDCP layer device under the ADAP layer device, integrity protection or integrity verification of the ADAP header or data (eg, ADAP SDU) may be performed. Here, the second light PDCP layer device may include a PDCP layer device that does not perform an encryption and decryption procedure with a heavy processing burden. That is, when data is transferred from the ADAP layer device to the lower layer device, the second light PDCP layer device set at the lower level is an ADAP header or data (eg, ADAP SDU) of the upper layer device, the ADAP layer device. ) Can be transmitted and transmitted to the lower layer by performing integrity protection only.

In addition, a separate second light PDCP layer device set under the ADAP layer device may perform only the integrity verification procedure for data including the ADAP header when receiving data from the lower layer.

The second light PDCP layer device may be implemented by a method in which the encryption and decryption functions are not set or deactivated in the second PDCP layer device. Alternatively, the complexity may be reduced by applying the encryption and decryption procedure or the integrity protection and verification procedure to only the upper layer header (eg, the ADAP header or the upper layer header).

In addition, as described above, the second PDCP layer device set for each bearer or RLC channel under the ADAP layer device of the wireless node receives data from the lower layer and performs integrity verification. It can be regarded as an attack and destroy data to perform defense. In addition, when an integrity verification failure occurs, it may be reported to an upper layer device (for example, an RRC layer device) to declare a wireless connection failure and to reestablish a wireless connection with another wireless node to prevent additional attacks. If an error occurs in a normal packet rather than an attack, the wireless node may notify the transmitting end of the integrity verification failure and request retransmission. For example, new PDCP control data may be defined, an existing PDCP status report may be modified, or an indicator of a PDCP header may be defined to indicate that data is lost due to integrity verification failure or request to be retransmitted.

The ADAP layer device described in the present disclosure may also be referred to by different names, such as a multi-hop adaptation protocol MAP (MAP) layer device or a backhaul adaptation protocol (BAP) layer device. However, only the names to be referred to are different, and the functions of the hierarchical device may operate the same.

In the present disclosure, in order to enhance the security of data transmitted between wireless nodes (for example, to enhance security for each wireless hop or to enhance end-to-end security between F1 interfaces), a bearer set in the wireless node or Embodiments and methods for enhancing security by setting a separate second PDCP layer device for each RLC channel have been described.

The following describes how to add security enhancement to the ADAP layer device itself, which serves to route data between wireless nodes, rather than setting a separate second PDCP layer device. That is, in order to enhance security of data transmitted between wireless nodes without having to set up a separate second PDCP layer device (for example, to enhance security for each wireless hop, or end-to-end security between F1 interfaces) Describes how to add the ability to encrypt and decrypt ADAP headers or data (e.g., ADAP SDUs) in an ADAP layer device or to perform integrity protection or integrity verification in order to enhance the castle. As described above, only the integrity protection or verification function may be introduced into the ADAP layer device in order to reduce the implementation complexity of the wireless node. And the encryption and decryption or integrity protection and verification function can be activated (or set) or disabled (or not set) in the top-level wireless node or parent mode.

When routing data between wireless nodes, wireless nodes determine routing through an ADAP layer device. And, the ADAP header generated by the ADAP layer device may include a terminal bearer identifier or a terminal identifier or a routing identifier or a wireless node address or QoS information. Therefore, if the information is changed by a hacker, routing problems may occur when data is transmitted between wireless nodes, and data may not be properly transmitted to a terminal corresponding to a destination address of data, and data may be lost. .

Therefore, in the present disclosure, due to this security problem, security is provided to the ADAP layer device for hop-by-hop authentication and protection of headers (for example, ADAP headers or higher layer headers) between wireless nodes and data. Describes how to add features. This security function can be embodied in the following ways.

Set encryption and decryption or integrity protection and verification algorithms on the ADAP layer device, apply encryption and decryption or integrity protection and verification procedures to headers (e.g., ADAP header or higher layer headers) and data, to the lower layer. It can transmit header and data with encryption or integrity protection. And, for the received data, the ADAP layer device applies a decryption or integrity verification procedure to the header (eg, ADAP header or data) and data, and if the integrity verification failure occurs for the received data, the corresponding data Can be considered as an attack and you can take steps to discard the data. In addition, an integrity failure has occurred in the upper layer device (for example, the RRC layer device), and an attack is reported, and the upper layer device may disconnect and instruct a new connection.

At this time, the encryption and decryption procedure is not set or added as a function of the ADAP layer device, and only the integrity protection or verification function is added to the ADAP layer device to reduce the implementation complexity of the wireless node. Alternatively, the complexity may be reduced by applying the encryption and decryption procedure or the integrity protection and verification procedure to only the upper layer header (for example, the ADAP header or the upper layer header).

At this time, the encryption and decryption algorithm or the integrity protection or verification algorithm may be set from an upper parent wireless node or an uppermost wireless node (IAB donor), and whether each function is activated (or set) or a security key (for example, a public key) Alternatively, a private key or an authentication key, etc.) may also be determined and set from a parent IAB node or a top-level wireless node. For example, each wireless node may perform a procedure of establishing a security key or a security algorithm (encryption and decryption or integrity protection or integrity verification) with an RRC message with the parent radio node or top-level radio node. In addition, the security key can be reused (for example, if a security key is applied by a PDCP layer device connected to an RRC layer device that is newly allocated by the parent wireless node or the top wireless node or connected to the RRC layer device currently used by the wireless node). ADAP layer device). Alternatively, to reduce the signaling overhead from each wireless node to the top-level parent wireless node, a security key or security algorithm (encryption and decryption or encryption) is used as a hop-by-hop security association establishment procedure between wireless nodes. Procedures for establishing integrity protection or integrity verification may be introduced and applied. The security key or algorithm (or security enhancement method) is applied by the PDCP layer device connected to the RRC layer device currently used by the wireless node, or newly allocated by the parent wireless node between wireless nodes (or exchanging security keys with each other). If there is a security key, it can be set to be reused (for example, in an ADAP layer device).

At this time, if the ADAP layer device applies the integrity protection or verification procedure to the upper layer header (for example, the ADAP header or upper layer header) or data, a separate security/authentication code to perform integrity verification in the receiving ADAP layer device. After deriving and generating a usage value (for example, a token or checksum field or a MAC-I field), transmission can be performed by configuring with an upper layer header or data to which integrity protection is applied. . Then, the receiving ADAP layer device performs an integrity verification procedure on the received header or data (for example, after deriving a separate security/authentication code by itself from the receiving end with a security algorithm) to the received header or data. You can check whether the values are the same by checking the values of the separate security/authentication codes included. If the values are the same, the integrity verification has been successfully performed. If the values are different, it can be considered that the integrity verification has failed.

In this case, a separate security/authentication code may be defined (and transmitted) as a field of the upper layer header (eg, ADAP header) and used (or transmitted). In another method, integrity protected header or data You can also attach it to the back and send it. The separate security/authentication code is defined as a fixed size so that the length field for indicating the size (or length) of the separate security/authentication code is not required, and is secured in the ADAP layer device of the transmitting and receiving terminal while having a fixed size. It can facilitate the implementation of the procedure.

In addition, by defining ADAP control data (ADAP control PDU), it is possible to share or verify a security key (or part of a security key) with each other between ADAP layer devices (wireless nodes) as ADAP control data rather than RRC messages. The ADAP control data may indicate a security key or a wireless node identifier or a security algorithm (or method), and may indicate whether the ADAP control data or ADAP layer device data is successfully received, and encrypt and decrypt or protect integrity. It may also include an indicator to activate or deactivate the verification procedure. Security procedures (encryption and decryption or integrity protection and verification) may not be applied to ADAP control data. In addition, the ADAP header may include an indicator indicating whether the ADAP layer device data is ADAP control data (ADAP control PDU) or ADAP user data (ADAP data PDU).

In addition, a new ADAP control PDU or BAP control PDU can be defined to control data flow or network congestion in a wireless backhaul network. For example, when the amount of data stored in the wireless node is higher than a certain threshold and transmission can no longer be performed, for example, if there is insufficient transmission resource and network congestion is expected, the newly defined first BAP control data (BAP control PDU) may be defined and trigger generation of the first BAP control data. In this case, the first BAP control data includes information on the amount of data stored or not transmitted for each terminal or for each bearer or RLC channel, and transmitted to a wireless node or a parent wireless node or a top-level wireless node. Information can be indicated by feedback on the network congestion status. A radio node or a parent radio node or a top-level radio including information such as an identifier of a terminal or a bearer identifier or an RLC channel identifier or a BAP address or a BAP path identifier of a terminal causing or congesting network congestion in the first BAP control data The network congestion status can be indicated by transmitting to a node. In addition, instead of the first BAP control data, the MAC layer device may be instructed to trigger a buffer status report. In this case, the MAC layer device of the wireless node may configure a buffer status report with MAC control information and transmit the data to the wireless node or the parent wireless node or the highest wireless node to indicate the network congestion state. In addition, when the first BAP control data includes an indicator to trigger the first BAP control data in the BAP control data received from the wireless node or the parent wireless node, the child wireless node, or the highest wireless node, the first BAP control data You can trigger and generate data. As another method, when an instruction is set to trigger the first BAP control data as a 1-bit indicator of a BAP header of data (BAP PDU) received from a radio node or a parent radio node or a child radio node or a top-level radio node, Trigger and generate BAP control data of 1. As another method, a timer is set as an RRC message to periodically trigger and generate the first BAP control data whenever the timer expires, and whenever the first BAP control data is triggered and generated or transmitted. The timer can be restarted every time. In addition, when a wireless connection failure occurs or when the wireless connection is released or when the wireless connection is changed to another wireless node, the corresponding timer may be stopped, initialized, or released. In addition, the radio node or the parent radio node or the highest radio node that has received the first BAP control data may adjust network traffic for the radio node. Here, when generating and configuring the first BAP control data, among the BAP control data, an identifier indicating the first BAP control data may be included and transmitted. For example, an identifier for distinguishing the second BAP control data from the first BAP control data can be introduced. In addition, a new ADAP control PDU or BAP control PDU can be defined to report the wireless connection status or wireless connection failure of the wireless backhaul network. For example, in the IAB-MT of the wireless node, the parent wireless node or the top wireless node or wireless If a radio link failure (RLF) is detected with a node, the IAB-DU of the radio node triggers and generates the newly defined second BAP control data to indicate that a radio link failure has occurred. Or, it may indicate to the top-level wireless node. At this time, the second BAP control data may include an address or a path identifier or a BAP address or a wireless connection failure indicator of a wireless node where a wireless connection failure has occurred. In addition, since the wireless connection is failed at the wireless node, the wireless connection failure is indicated as the second BAP control data, and data such as a destination address, a BAP address, or a path identifier to be newly transmitted to a wireless node or a child wireless node or to establish a new connection. Information may be included in the second BAP control data and transmitted.

If the second BAP control data is received, the BAP layer device of the IAB-MT of the wireless node that received the second BAP control data does not confirm successful delivery from the lower layer device (eg, RLC layer device). A new wireless link or a newly established wireless link for unused data (eg, BAP PDU or BAP SDU) or for data not yet delivered to a lower layer device (eg, BAP PDU or BAP SDU). Transmission or retransmission may be performed by re-routing the data to a radio link or an address indicated by the raw or second BAP control data. In another method, the BAP layer device of the IAB-MT of the wireless node that has received the second BAP control data has data that has not been successfully delivered from the lower layer device (eg, RLC layer device) (eg, BAP). Re-generate BAP headers for PDUs or BAP SDUs or for data that has not yet been delivered to a lower layer device (e.g., BAP PDUs or BAP SDUs) and re-create a new BAP header in the BAP header or a new wireless link. Or re-generate data (BAP PDU) including the radio link or address or BAP address or path identifier indicated by the second BAP control data, and re-route the data to a new radio link or a radio link to establish a new connection. The transmission or retransmission may be performed to the radio link or address indicated by the raw or second BAP control data. If the second BAP control data is received, the wireless node that has received the second BAP control data may re-establish RLC layer devices (RLC re-establishment) or initialize the MAC layer device (MAC reset). Can.

In addition, in the present disclosure, when a parent radio node or a top-level radio node instructs handover of a radio node with an RRC message, or when setting information of a BAP layer device is reset with an RRC message, or wirelessly with second BAP control data When the connection failure is indicated, when the BAP layer device configuration information is reset through a handover message or an RRC message, or when second BAP control data is received, the wireless node (or RRC layer device of the wireless node) is a BAP layer device. BAP re-establishment procedures can be instructed. The re-establishment procedure of the BAP layer device may reset mapping configuration information of the RLC channel set in the RRC message or routing configuration information of the radio link to the BAP layer device. In addition, the re-establishment procedure of the BAP layer device includes data in which the BAP layer device of the IAB-MT of the wireless node has not been successfully delivered from the lower layer device (eg, RLC layer device) (eg, BAP PDU or BAP). SDU) or for a data that has not yet been delivered to a lower layer device (for example, a BAP PDU or a BAP SDU), re-generates a BAP header and establishes a new radio link or a new connection in the BAP header or a second link. Re-generates the data (BAP PDU) including the wireless link or address or BAP address or path identifier indicated by the BAP control data, and transmits or re-routes the data to a new wireless link or to a new wireless link. It may include a procedure of performing transmission or retransmission to a radio link or an address indicated by the RRC message or the RRC message indicated by the second or second BAP control data. In addition, when performing the re-establishment procedure of the BAP layer device, the wireless node may re-establish RLC layer devices (RLC re-establishment) or initialize the MAC layer device (MAC reset).

Here, when generating and configuring the second BAP control data, an identifier indicating the second BAP control data among the BAP control data may be included and transmitted. For example, an identifier for distinguishing the second BAP control data from the first BAP control data can be introduced.

Accordingly, in the wireless backhaul network described in the present disclosure, when the wireless node receives the BAP control data, it checks the identifier of the BAP control data to determine whether it is the first BAP control data or the second BAP control data, and if so, If one BAP control data is the first BAP control data, the processing or procedure is performed as described above, and if the received BAP control data is the second BAP control data, the processing or procedure is performed as described above. Can.

FIG. 2L is a diagram illustrating an operation of a wireless node (the highest-level wireless node or an intermediate node or terminal) according to an embodiment.

In FIG. 2L, it is necessary to strengthen security in a wireless link or a wireless section (for example, a wireless link between a terminal and a wireless node or between a terminal and a top-level node or between a wireless node and a top-level wireless node accessed by a terminal in a wireless backhaul network). When it is judged (2l-05), for example, when security enhancement is required for the F1 interface, the top-level wireless node is separately provided to the end wireless nodes of the F1 interface (for example, the top-level wireless node and the wireless node connected to the terminal). By setting the upper layer device (e.g., IPsec layer device or second PDCP layer device) (2l-15), and setting and performing encryption and decryption or integrity protection and verification procedures in a separate upper layer device. Security can be enhanced (2l-20). When receiving the data, the wireless node or the top-level node may perform decryption or integrity verification in a separate upper layer device to prevent unexpected attacks or check data errors or data integrity.

2M shows the structure of a terminal or a wireless node according to an embodiment.

Referring to Figure 2m, the above-described terminal includes a radio frequency (RF) processor (2m-10), a baseband (baseband) processor (2m-20), a storage unit (2m-30) and a controller (2m-40) do.

The RF processor 2m-10 may perform a function for transmitting and receiving a signal through a wireless channel such as band conversion and amplification of the signal. That is, the above-described RF processing unit (2m-10) up-converts the baseband signal provided from the above-described baseband processing unit (2m-20) into an RF band signal, transmits it through an antenna, and receives it through the above-described antenna. The RF band signal can be down-converted to a baseband signal. For example, the above-described RF processing unit (2m-10) includes a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), and an analog to digital converter (ADC). can do. In the above-described drawings, only one antenna is shown, but the above-described terminal may include a plurality of antennas. In addition, the RF processing unit 2m-10 described above may include a plurality of RF chains. Furthermore, the above-described RF processing unit 2m-10 may perform beamforming. For the above-described beamforming, the above-described RF processing unit 2m-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. In addition, the above-described RF processor may perform multi input multi output (MIMO), and may receive multiple layers when performing MIMO operation. The RF processing unit 2m-10 described above performs reception beam sweeping by appropriately setting a plurality of antennas or antenna elements under the control of the control unit, or adjusts the direction and beam width of the reception beam so that the reception beam is coordinated with the transmission beam. Can.

The baseband processing unit 2m-20 may perform a conversion function between a baseband signal and a bit stream according to a physical layer standard of the system. For example, when transmitting data, the baseband processor 2m-20 may generate complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit 2m-20 may restore the received bit string through demodulation and decoding of the baseband signal provided from the RF processing unit 2m-10. For example, in the case of conforming to the orthogonal frequency division multiplexing (OFDM) method, when transmitting data, the baseband processor 2m-20 generates complex symbols by encoding and modulating a transmission bit string, and mapping the complex symbols to subcarriers. After that, OFDM symbols may be configured through an inverse fast Fourier transform (IFFT) operation and a cyclic prefix (CP) insertion. In addition, when receiving data, the above-described baseband processing unit 2m-20 divides the baseband signal provided from the RF processing unit 2m-10 into units of OFDM symbols and transmits to subcarriers through fast Fourier transform (FFT) operation. After restoring the mapped signals, the received bit stream may be reconstructed through demodulation and decoding.

The baseband processing unit 2m-20 and the RF processing unit 2m-10 transmit and receive signals as described above. Accordingly, the baseband processor 2m-20 and the RF processor 2m-10 may be referred to as a transmitter, a receiver, a transceiver, or a communicator. Furthermore, at least one of the baseband processing unit 2m-20 and the RF processing unit 2m-10 may include a plurality of communication modules to support a plurality of different radio access technologies. Further, at least one of the baseband processing unit 2m-20 and the RF processing unit 2m-10 may include different communication modules to process signals of different frequency bands. For example, the different radio access technologies described above may include LTE networks, NR networks, and the like. In addition, the different frequency bands described above may include a super high frequency (SHF) band (eg, 2.2 gHz, 2ghz), and a millimeter wave (mm band) (eg, 60 GHz) band. The terminal may transmit and receive signals to and from the base station using the baseband processor 2m-20 and the RF processor 2m-10. Here, the signal may include control information and data.

The storage unit 2m-30 may store data such as a basic program, application program, and setting information for the operation of the above-described terminal. The storage unit 2m-30 may provide stored data according to the request of the control unit 2m-40 described above. The storage unit 2m-30 may be composed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM and a DVD, or a combination of storage media. Also, the storage unit 2m-30 may be configured with a plurality of memories. In one embodiment, the storage unit 2m-30 may store a program for supporting beam-based cooperative communication.

The control unit 2m-40 controls overall operations of the above-described terminal. For example, the control unit 2m-40 may transmit and receive signals through the baseband processing unit 2m-20 and the RF processing unit 2m-10. In addition, the control unit 2m-40 can record and read data in the storage unit 2m-40. To this end, the control unit 2m-40 may include at least one processor. For example, the controller 2m-40 may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls an upper layer such as an application program. According to one embodiment, the control unit 2m-40 may include a multiple connection processing unit 2m-42 configured to process a process operating in a multiple connection mode.

2N is a block diagram showing the configuration of a TRP device or a wireless node in a wireless communication system according to an embodiment.

Referring to FIG. 2N, the base station includes an RF processing unit 2n-10, a baseband processing unit 2n-20, a backhaul communication unit 2n-30, a storage unit 2n-40, and a control unit 2n-50. .

The RF processing unit 2n-10 may perform a function for transmitting and receiving a signal through a wireless channel such as band conversion and amplification of the signal. That is, the RF processor 2n-10 converts the baseband signal provided from the baseband processor 2n-20 to an RF band signal, transmits it through an antenna, and transmits the RF band signal received through the antenna described above. It can be down-converted to a baseband signal. For example, the RF processing unit 2n-10 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, and A DC. In the above-described drawings, only one antenna is shown, but the first access node may include a plurality of antennas. Also, the RF processing unit 2n-10 may include a plurality of RF chains. Furthermore, the RF processing unit 2n-10 may perform beamforming. For beamforming, the RF processing unit 2n-10 may adjust the phase and magnitude of each of signals transmitted and received through a plurality of antennas or antenna elements. The above-described RF processor may perform a downlink MIMO operation by transmitting one or more layers.

The baseband processor 2n-20 may perform a conversion function between the baseband signal and the bit stream according to the physical layer standard of the first radio access technology. For example, when transmitting data, the baseband processor 2n-20 may generate complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the baseband processing unit 2n-20 may restore the received bit string through demodulation and decoding of the baseband signal provided from the RF processing unit 2n-10. For example, according to the OFDM method, when transmitting data, the baseband processor 2n-20 generates complex symbols by encoding and modulating the transmission bit string, mapping the complex symbols to subcarriers, and then performing IFFT operation and OFDM symbols can be configured through CP insertion. In addition, when receiving data, the baseband processing unit 2n-20 divides the baseband signal provided from the RF processing unit 2n-10 into OFDM symbol units and restores signals mapped to subcarriers through FFT calculation. , It is possible to restore the received bit stream through demodulation and decoding. The baseband processor 2n-20 and the RF processor 2n-10 may transmit and receive signals as described above. Accordingly, the baseband processor 2n-20 and the RF processor 2n-10 may be referred to as a transmitter, a receiver, a transceiver, a communication unit, or a wireless communication unit.

The communication unit 2n-30 may provide an interface for performing communication with other nodes in the network. The base station may transmit and receive signals to and from the terminal using the baseband processor 2n-20 and the RF processor 2n-10. Here, the signal may include control information and data.

The storage unit 2n-40 may store data such as a basic program, an application program, and setting information for the operation of the main station described above. In particular, the storage unit 2n-40 may store information on bearers allocated to the connected terminal, measurement results reported from the connected terminal, and the like. In addition, the storage unit 2n-40 may store information serving as a criterion for determining whether to provide or stop multiple connections to the terminal. Then, the storage unit 2n-40 may provide stored data according to the request of the control unit 2n-50. The storage unit 2n-40 may be composed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM and a DVD, or a combination of storage media. Also, the storage unit 2n-40 may be configured with a plurality of memories. In one embodiment, the storage unit 2n-40 may store a program for supporting beam-based cooperative communication.

The control unit 2n-50 can control the overall operations of the main station. For example, the control unit 2n-50 may transmit/receive signals through the baseband processing unit 2n-20 and the RF processing unit 2n-10 or through the backhaul communication unit 2n-30. In addition, the control unit 2n-50 can record and read data in the storage unit 2n-40. To this end, the control unit 2n-50 may include at least one processor. According to an embodiment, the control unit 2n-50 may include a multiple connection processing unit 2n-52 configured to process a process operating in a multiple connection mode.

The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured to be executable by one or more processors in an electronic device. One or more programs include instructions that cause an electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

Such programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (EEPROM: Electrically Erasable Programmable Read Only Memory), magnetic disc storage device (CD-ROM: Compact Disc-ROM), digital versatile discs (DVDs) or other forms It can be stored in an optical storage device, a magnetic cassette. Or, it may be stored in a memory composed of a combination of some or all of them. Also, a plurality of configuration memories may be included.

In addition, the program may be accessed through a communication network composed of a communication network such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), or a storage area network (SAN), or a combination thereof. It may be stored in an attachable storage device. Such a storage device can access a device performing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may access a device performing an embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, elements included in the present invention are expressed in singular or plural according to the specific embodiments presented. However, the singular or plural expressions are appropriately selected for the situations presented for convenience of description, and the present disclosure is not limited to the singular or plural components, and even the components expressed in plural are composed of singular or Even the expressed components may be composed of a plurality.

On the other hand, the embodiments of the present disclosure disclosed in the specification and drawings are merely to provide a specific example to easily describe the technical content of the present disclosure and to understand the present disclosure, and are not intended to limit the scope of the present disclosure. That is, it is obvious to those skilled in the art to which other modifications based on the technical spirit of the present disclosure can be practiced. In addition, each of the above embodiments can be operated in combination with each other as necessary. For example, a part of one embodiment of the present disclosure and a part of another embodiment may be combined with each other to operate a base station and a terminal. In addition, other modifications based on the technical idea of the above embodiment may be implemented in various systems such as an FDD LTE system, a TDD LTE system, and a 5G or NR system.

Claims (1)

In the data processing method in a transmission apparatus of a wireless communication system,
Determining whether to divide the data by determining whether the data received from the upper layer device is a size that can be processed by the layer device receiving the data;
If it is decided to divide the data, performing data division; And
And performing data processing by classifying the divided first data, last data, and intermediate data.

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