KR20210088382A - Method and apparatus for changing of pdu session and always-on pdu session in a wireless communication system - Google Patents

Abstract

The present disclosure relates to a communication technique which converges a 5G communication system for supporting a higher data transmission rate than a 4G system with IoT technology, and a system thereof. The present disclosure can be applied to intelligent services (for example, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety-related services, etc.) based on 5G communication technology and IoT-related technology. A control signal processing method in a wireless communication system includes the steps of: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

Description

Method and apparatus for changing PDU Session and Always-on PDU Session in a wireless communication system {METHOD AND APPARATUS FOR CHANGING OF PDU SESSION AND ALWAYS-ON PDU SESSION IN A WIRELESS COMMUNICATION SYSTEM}

The present disclosure relates to a communication system, and more particularly, to a PDU Session management method for a URLLC service.

Efforts are being made to develop an improved 5th generation (5G) communication system or a pre-5G communication system in order to meet the increasing demand for wireless data traffic after commercialization of the 4G (4th generation) communication system. For this reason, the 5G communication system or the pre-5G communication system is called a 4G network after (Beyond 4G Network) communication system or an LTE (Long Term Evolution) system after (Post LTE) system.

In order to achieve high data rates, 5G communication systems are being considered for implementation in very high frequency (mmWave) bands (eg, 60 gigabytes (60 GHz) bands). In order to alleviate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, in the 5G communication system, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed.

In addition, for network improvement 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 (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and reception interference cancellation Technology development is underway.

In addition, in the 5G system, Hybrid Frequency Shift Keying and Quadrature Amplitude Modulation (FQAM) and Sliding Window Superposition Coding (SWSC), which are advanced coding modulation (Advanced Coding Modulation, ACM) methods, and Filter Bank Multi Carrier (FBMC), an advanced access technology, ), Non Orthogonal Multiple Access (NOMA), and Sparse Code Multiple Access (SCMA) are being developed.

The 5G system is considering support for various services compared to the existing 4G system. For example, the most representative services are enhanced mobile broadband (eMBB), ultra-reliable and low latency communication (URLLC), and massive device-to-device communication service (mMTC). machine type communication), next-generation broadcast service (eMBMS: evolved multimedia broadcast/multicast Service), and the like. In addition, the system providing the URLLC service may be referred to as a URLLC system, and the system providing the eMBB service may be referred to as an eMBB system. Also, the terms service and system may be used interchangeably.

Among them, the URLLC service is a service newly considered in the 5G system, unlike the existing 4G system, and has ultra-high reliability (eg, about 10-5 packet error rate) and low latency (eg, about 0.5 msec) requirement to be satisfied. In order to satisfy such strict requirements, the URLLC service may need to apply a shorter transmission time interval (TTI) than the eMBB service, and various operating methods are being considered using this.

On the other hand, the Internet is evolving from a human-centered connection network where humans create and consume information to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers, etc. with IoT technology, is also emerging. In order to implement IoT, technology 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 and a machine to machine communication (Machine to Machine) are required. , M2M), and MTC (Machine Type Communication) are being studied.

In the IoT environment, an intelligent IT (Internet Technology) service that collects and analyzes data generated from connected objects and creates new values in human life can 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, advanced medical service, etc. through the convergence and complex between existing IT (information technology) technology and various industries. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication) are implemented by 5G communication technologies such as beamforming, MIMO, and array antenna. will be. The application of a cloud radio access network (cloud RAN) as the big data processing technology described above is an example of the convergence of 5G technology and IoT technology.

As various services can be provided according to the above-mentioned and the development of mobile communication systems, there is a need for a method for efficiently using a Non-Public Network (NPN).

The disclosed embodiment is intended to provide a method and apparatus for effectively providing a service in a wireless communication system.

The present invention for solving the above problems is a control signal processing method in a wireless communication system, the method comprising: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

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

1 shows the structure of a 5G network according to an embodiment of the present disclosure.
2 illustrates a PDU Session Modification procedure according to an embodiment of the present disclosure.
3 is a flow chart showing the operation of the SMF when a new QoS Flow is generated according to an embodiment of the present disclosure.
4 is a flow chart showing the operation of the SMF when the QoS Flow is released according to an embodiment of the present disclosure.
5 is a flow chart illustrating an operation of a UE when a new QoS Flow is generated according to an embodiment of the present disclosure.
6 is a flow chart illustrating an operation of a UE when QoS Flow is released according to an embodiment of the present disclosure.
7 illustrates a PDU Session Establishment procedure according to an embodiment of the present disclosure.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. At this time, it should be noted that in the accompanying drawings, the same components are denoted by the same reference numerals as possible. In addition, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted.

In describing embodiments in the present specification, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention without obscuring the gist of the present invention by omitting unnecessary description.

For the same reason, some components are exaggerated, omitted, or schematically illustrated in the accompanying drawings. In addition, the size of each component does not fully reflect the actual size. In each figure, the same or corresponding elements are assigned the same reference numerals.

Advantages and features of the present invention, and a method for achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains. It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. It is also possible that the instructions stored in the flow chart block(s) produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for performing the functions described in the flowchart block(s).

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

At this time, the term '~ unit' used in this embodiment means software or hardware components such as FPGA or ASIC, and '~ unit' performs certain roles. However, '-part' is not limited to software or hardware. The '~ unit' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Thus, as an example, '~' denotes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, components and '~ units' may be implemented to play one or more CPUs in a device or secure multimedia card.

Hereinafter, the base station, as a subject performing resource allocation of the terminal, is at least one of Node B, BS (Base Station), eNB (eNode B), gNB (gNode B), radio access unit, base station controller, or a node on the network. can The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. In addition, the embodiment of the present disclosure may be applied to other communication systems having a similar technical background or channel type to the embodiment of the present disclosure described below. In addition, the embodiments of the present disclosure may be applied to other communication systems through some modifications within a range that does not significantly depart from the scope of the present disclosure as judged by a person having skilled technical knowledge.

A term for identifying an access node used in the following description, a term referring to a network entity or NF (network functions), a term referring to messages, a term referring to an interface between network objects, various Terms and the like referring to identification information are exemplified for convenience of description. Therefore, the present invention is not limited to the terms described below, and other terms referring to objects having equivalent technical meanings may be used.

For convenience of description below, some terms and names defined in the 3rd generation partnership project long term evolution (3GPP) standard may be used. However, the present invention is not limited by the above terms and names, and may be equally applied to systems conforming to other standards.

Embodiments of the present disclosure change a PDU Session configured for an Ultra Reliable and Low Latency Communication (URLLC) service to an Always-on PDU Session depending on the presence or absence of a URLLC service, or a method for changing an Always-on PDU Session to a PDU Session provides

1 shows the structure of a 5G network according to an embodiment of the present disclosure. The description of the network entities or network nodes constituting the 5G network is as follows.

(R) AN ((Radio) Access Network) is a subject that performs radio resource allocation of the terminal, eNode B, Node B, BS (Base Station), NG-RAN (NextGeneration Radio Access Network), 5G-AN, radio It may be at least one of a connection unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a next generation UE (NG UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function. In addition, although the embodiment of the present disclosure will be described below using the 5G system as an example, the embodiment of the present disclosure may be applied to other communication systems having a similar technical background. In addition, the embodiments of the present disclosure may be applied to other communication systems through some modifications within a range that does not significantly depart from the scope of the present disclosure as judged by a person having skilled technical knowledge.

As the wireless communication system evolves from a 4G system to a 5G system, a new Core Network, NextGen Core (NG Core) or 5GC (5G Core Network) is defined. The new Core Network virtualized all the existing network entities (NE: Network Entity) and made it into a Network Function (NF: Network Function). According to an embodiment of the present disclosure, a network function may mean a network entity, a network component, and a network resource.

According to an embodiment of the present disclosure, 5GC may include the NFs shown in FIG. 1 . Of course, it is not limited to the example of FIG. 1 , and 5GC may include a larger number of NFs or a smaller number of NFs than the NFs shown in FIG. 1 .

According to an embodiment of the present disclosure, an Access and Mobility Management Function (AMF) may be a network function for managing the mobility of a terminal.

According to an embodiment of the present disclosure, a Session Management Function (SMF) may be a network function for managing a Packet Data Network (PDN) connection provided to a terminal. The PDN connection may be referred to as a PDU (Protocol Data Unit) Session.

According to an embodiment of the present disclosure, a Policy Control Function (PCF) may be a network function that applies a service policy of a mobile communication operator to a terminal, a charging policy, and a policy for a PDU Session.

According to an embodiment of the present disclosure, Unified Data Management (UDM) may be a network function that stores information about a subscriber.

According to an embodiment of the present disclosure, a network exposure function (NEF) may be a function of providing information about a terminal to a server outside the 5G network. In addition, the NEF can provide the 5G network with the information necessary for service and provide a function to store it in the UDR.

According to an embodiment of the present disclosure, a user plane function (UPF) may be a function that serves as a gateway for transferring user data (PDU) to a data network (DN).

According to an embodiment of the present disclosure, a Network Repository Function (NRF) may perform a function of discovering the NF.

According to an embodiment of the present disclosure, an Authentication Server Function (AUSF) may perform terminal authentication in a 3GPP access network and a non-3GPP access network.

According to an embodiment of the present disclosure, a network slice selection function (NSSF) may perform a function of selecting a network slice instance provided to the terminal.

According to an embodiment of the present disclosure, a DN (Data Network) may be a data network through which a terminal transmits and receives data in order to use a service of a network operator or a 3rd party service.

2 illustrates a PDU Session Modification procedure according to an embodiment of the present disclosure.

Steps 1a-1f show events in which the PDU Session Modification procedure is executed. Step 1a shows that the UE starts to change the PDU Session while sending the PDU Session Modification Request message to the SMF through the AMF. This message includes parameters such as PDU Session ID, Packet Filters, Operation, Requested QoS, Segregation, 5GSM Core Network Capability, Number Of Packet Filters, [Always-on PDU Session Requested], [Always-on PDU Session Release Requested], etc. can be

In order to request QoS handling for a specific Service Data Flow (SDF), the UE may include Operation, Requested QoS, and Segregation related to Packet Filters that can specify the SDF.

When handing over a PDU Session generated in EPS (Evolved Packet System) from EPS to 5GS, the UE may include an Always-on PDU Session Requested indication to change the PDU Session to an always-on PDU Session. In addition, when a new URLLC service is started and a URLLC QoS Flow is transmitted using an existing PDU Session, the UE may include an Always-on PDU Session Requested indication to change the existing PDU Session to an Always-on PDU Session. Conversely, when the service using the existing URLLC QoS Flow is terminated and the Always-on PDU Session is no longer required, the UE may include an Always-on PDU Session Release Requested indication. When the UE changes the Always-on PDU Session to the PDU Session, the UE can determine whether the PDU Session is created as an Always-on PDU Session for other reasons as well as reliable transmission (Establishment). If an Always-on PDU Session is created for other reasons, SMF may not change the Always-on PDU Session to a PDU Session.

On the other hand, the UE may be in a CM-IDLE (Connection Management-IDLE) or CM-CONNECTED (Connection Management-CONNECTED) state according to the presence or absence of a NAS Signaling Connection (N1 connection) with the AMF. In this case, the UE must be in the CM-CONNECTED state in order to transmit and receive user data and control signals with the base station or network.

In Always-on PDU Session, User Plane (UP) connection is always activated when the UE transitions from CM-IDLE state to CM-CONNECTED state. Also, in general, SMF deactivates the UP connection if data is not transmitted in the PDU Session for a while, but this is not applied to the Always-on PDU Session. That is, in the Always-on PDU Session, the UP connection is always activated while the UE is in the CM-CONNECTED state. It is very important to create an Always-on PDU Session for the PDU Session that transmits the URLLC QoS Flow because the service may fail due to the UP connection setup time in providing the URLLC service, which is very sensitive to delay.

As a supplementary description for the CM-IDLE state and the CM-CONNECTED state, the UE does not have an AMF and NAS signaling connection (N1 connection) in the CM-IDLE state. In this case, not only the AN signaling connection with the NG-RAN but also the N2 connection and the N3 connection for the corresponding UE may not exist. That is, in the CM-IDLE state, the UE cannot send and receive user data or control signals through uplink (UL) or downlink (DL). When a user data or control signal directed to the UE occurs, the network transitions to the CM-CONNECTED state through the network triggered Service Request procedure (paging transmission). Through the procedure, the UE transitions to the CM-CONNECTED state. In the CM-CONNECTED state, the UE has an AMF and NAS signaling connection (N1).

However, NG-RAN and UPF must always allocate resources for Always-on PDU Session because UP connection is always established even if there is no data to be transmitted in Always-on PDU Session, and unwanted signaling may occur. . Therefore, when there is no need to use Always-on PDU Session, it is desirable to change Always-on PDU Session to PDU Session.

In steps 1b, 1c, and 1d, it is the PDU Session Modification requested by the SMF. This can occur when policy is changed by PCF, when subscription data is changed by UDM, or when a change request is received from (R)AN by configured policy in SMF or (R)AN.

Steps 1e and 1f are cases in which PDU Session Modification is requested by AN and AMF requests, respectively.

In steps 2a and 2b, the SMF may determine whether to perform reliable transmission using redundant transmission for a specific QoS Flow based on authorized 5QI, NG-RAN node capability, and operator configuration information. That is, it is determined whether a specific QoS Flow is for URLLC service. If the SMF determines that it is a QoS Flow for the URLLC service, the SMF allocates additional CN Tunnel Info and transmits it to the UPF, thereby establishing two GTP-U tunnels between the NG-RAN and the UPF. In addition, the SMF instructs the UPF to perform packet duplication (in case of DL) and packet elimination (in case of UL) in order to perform double transmission using two GTP-U tunnels for packets transmitted in the corresponding QoS Flow. If the additional CN Tunnel Info is allocated by the UPF, the SMF allocates the additional CN Tunnel Info to the UPF and informs the SMF of this.

Conversely, the SMF may decide whether to stop reliable transmission for QoS Flow for the existing URLLC service. The SMF may decide whether to stop reliable transmission based on authorized 5QI, NG-RAN node capability, and operator configuration information, or may decide to stop reliable transmission when the corresponding QoS Flow is no longer transmitted. At this time, the SMF instructs the UPF to release the additional CN Tunnel Info allocated to the UPF and stop the packet duplication (DL case) and packet elimination (UL case) operations for double transmission.

The SMF may perform dual transmission by setting two I-UPFs (Intermediate UPFs) between the NG-RAN and the PDU Session Anchor (PSA) UPFs. For this, the SMF allocates two I-UPFs and transmits their UL CN Tunnel Info to the PSA UPF, and transmits the DN CN Tunnel Info of the PSA UPF to the I-UPF. The PSA UPF request for duplex transmission and duplex transmission release are the same as described above.

In step 3a, when the UE or AN requests modification, the response to the request is performed through the N2 SM information (AN request) or PDU Session Modification Command (UE request) message encapsulated in the Nsmf_PDUSession_UpdateSMContext Response message.

PDU Session Modification Command message includes PDU Session ID, QoS rule(s), QoS rule operation, QoS Flow level, QoS parameters, Session-AMBR, [Always-on PDU Session Granted], [Always-on PDU Session Release Granted], etc. may include parameters of

The Always-on PDU Session Granted indication is a parameter sent by the SMF as a response when the UE requests to change the PDU Session to the Always-on PDU Session. Even if the UE does not send an Always-on PDU Session Request indication, if the SMF decides to perform reliable transmission for a specific QoS Flow in step 2a, the SMF sends this Always-on PDU Session Granted indication to the PDU Session Modification It can be included in the Command message to inform the UE that the corresponding PDU Session has been changed to an Always-on PDU Session. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, UP connection activation of the corresponding PDU Session must be requested. That is, in procedures such as Registration or Service Request, the UE may include the ID of the corresponding PDU Session in the List Of PDU Sessions To Be Activated parameter.

The Always-on PDU Session Release Granted indication is a parameter sent by the SMF as a response when the UE requests to change the Always-on PDU Session to a PDU Session. Even if the UE does not send the Always-on PDU Session Release Requested indication, if the SMF decides to stop reliable transmission for a specific QoS Flow in step 2a, the SMF sends this Always-on PDU Session Release Granted indication It can be included in the PDU Session Modification Command message to inform the UE that the Always-on PDU Session has been changed to a PDU Session. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, it requests UP connection activation of the corresponding PDU Session, so it is necessary to notify the UE to stop it. That is, in procedures such as Registration or Service Request, the UE may stop including the ID of the PDU Session in the List Of PDU Sessions To Be Activated parameter. When changing an Always-on PDU Session to a PDU Session without the UE's request, the SMF can determine whether the PDU Session was created as an Always-on PDU Session for other reasons as well as reliable transmission. If it is created for other reasons, SMF may not change the Always-on PDU Session to a PDU Session.

If the SMF decides to perform reliable transmission in step 2a, the N2 SM information includes CN Tunnel Info for an additional tunnel. In addition, the SMF instructs the NG-RAN to perform packet duplication (UL case) and packet elimination (DL case) for double transmission using two GTP-U tunnels for packets transmitted in the corresponding QoS Flow.

Conversely, the SMF may determine whether to stop reliable transmission for QoS Flow for the existing URLLC service. The SMF may decide whether to stop reliable transmission based on authorized 5QI, NG-RAN node capability, and operator configuration information, or may decide to stop reliable transmission when the corresponding QoS Flow is no longer transmitted. At this time, the SMF instructs the NG-RAN to stop the release of additional AN Tunnel Info and packet duplication (in case of UL) and packet elimination (in case of DL) for double transmission.

In step 3b, when the SMF requests modification, the change according to the modification is transmitted through the N2 SM information (AN) or PDU Session Modification Command (UE) message encapsulated in the Namf_Communication_N1N2MessageTransfer message.

The PDU Session Modification Command message includes PDU Session ID, QoS rule(s), QoS rule operation, QoS Flow level, QoS parameters, Session-AMBR, [Always-on PDU Session Granted], [Always-on PDU Session Release Granted], etc. may include parameters of

The Always-on PDU Session Granted indication is, in step 2a, if the SMF decides to perform reliable transmission for a specific QoS Flow, the SMF includes the Always-on PDU Session Granted indication in the PDU Session Modification Command message to the UE. It can inform that the corresponding PDU Session has been changed to an Always-on PDU Session. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, UP connection activation of the corresponding PDU Session must be requested. That is, in procedures such as Registration or Service Request, the UE may include the ID of the corresponding PDU Session in the List Of PDU Sessions To Be Activated parameter.

The Always-on PDU Session Release Granted indication is, in step 2a, if the SMF decides to stop reliable transmission for a specific QoS Flow, the SMF includes the Always-on PDU Session Release Granted indication in the PDU Session Modification Command message. to notify the UE that the Always-on PDU Session has been changed to a PDU Session. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, it requests UP connection activation of the corresponding PDU Session, so it is necessary to notify the UE to stop it. That is, in procedures such as Registration or Service Request, the UE may stop including the ID of the PDU Session in the List Of PDU Sessions To Be Activated parameter. When changing an Always-on PDU Session to a PDU Session without the UE's request, the SMF can determine whether the PDU Session was created as an Always-on PDU Session for other reasons as well as reliable transmission. If an Always-on PDU Session is created for other reasons, SMF may not change the Always-on PDU Session to a PDU Session.

If the SMF decides to perform reliable transmission in step 2a, the N2 SM information includes CN Tunnel Info for an additional tunnel. In addition, the SMF instructs the NG-RAN to perform packet duplication (UL case) and packet elimination (DL case) for double transmission using two GTP-U tunnels for packets transmitted in the corresponding QoS Flow.

Conversely, the SMF may determine whether to stop reliable transmission for QoS Flow for the existing URLLC service. The SMF may decide whether to stop reliable transmission based on authorized 5QI, NG-RAN node capability, and operator configuration information, or may decide to stop reliable transmission when the corresponding QoS Flow is no longer transmitted. At this time, the SMF instructs the NG-RAN to stop the release of additional AN Tunnel Info and packet duplication (in case of UL) and packet elimination (in case of DL) for double transmission.

In step 3c, when the SMF requests Modification due to the update of the SMF-related parameters from the UDM, the SMF can transmit related information to the AMF.

Through steps 4 and 5, the N1 SM container encapsulating the N2 SM information and the PDU Session Modification Command is transmitted to the NG-RAN and the UE.

In step 6, the NG-RAN allocates additional AN Tunnel Info for reliable transmission, and transmits it to the SMF through N2 SM information. (If the SMF decides to make a reliable transmission in step 2a).

In steps 7a and 7b, the AMF delivers N2 SM information to the SMF.

In steps 8a and 8b, the SMF transmits the additional AN Tunnel Info received from the NG-RAN to the UPF or I-UPF for reliable transmission. If the CN Tunnel Info of the I-UPF is allocated in the UPF in step 2b, the SMF delivers the DL CN Tunnel Info of the two I-UPFs to the PSA UPF.

In steps 9 to 11b, the UE sends an acknowledgment of the PDU Session Modification Command message, and the NG-RAN and the AMF deliver it to the SMF.

In step 12, the SMF may update the N4 session with the UPF.

In step 13, the SMF notifies the PCF of whether the PCC decision is reflected or not.

7 illustrates a PDU Session Establishment procedure according to an embodiment of the present disclosure.

In step 1, the UE encapsulates the PDU Session Establishment Request message in the NAS Message to create a PDU Session and delivers it to the SMF through the AMF. When the UE intends to establish a PDU Session supporting URLLC QoS Flow, the UE requests Always-on PDU Session establishment by including an Always-on PDU Session Requested indication in the PDU Session Establishment Request message.

In step 11, the SMF transmits the PDU Session Establishment Accept message to be transmitted to the UE to the encapsulation AMF in the Namf_Communication_N1N2MessageTransfer message. If the UE requests Always-on PDU Session creation by including the Always-on PDU Session Requested indication in the PDU Session Establishment Request message, the SMF may respond to the request through the PDU Session Establishment Accept message. If the SMF permits this, the Always-on PDU Session Granted indication may be included in the PDU Session Establishment Accept message. Even if the UE does not send an Always-on PDU Session Request indication in the PDU Session Establishment Request message, if the SMF determines that Always-on PDU Session is necessary, the Always-on PDU Session Granted indication is included in the PDU Session Establishment Accept message. can do. If the SMF decides to perform reliable transmission for specific QoS Flows in step 10a, the SMF may include an Always-on PDU Session Granted indication in the PDU Session Establishment Accept message. Through this, it is possible to inform the UE that the corresponding PDU Session has been established as an Always-on PDU Session. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, UP connection activation of the corresponding PDU Session must be requested. That is, in procedures such as Registration or Service Request, the UE may include the ID of the corresponding PDU Session in the List Of PDU Sessions To Be Activated parameter.

3 is a flow chart showing the operation of the SMF when a new QoS Flow is generated according to an embodiment of the present disclosure. Hereinafter, each step disclosed in FIG. 3 will be described as being performed by itself by the SMF for purposes of illustration, but this does not limit the scope of the present disclosure and can be performed by a person skilled in the art to which the present disclosure belongs. may be performed according to an embodiment of the present invention, for example, may be performed by any configuration provided to perform each step according to the request of the SMF.

In step 301, when a new QoS Flow is generated, the SMF may determine whether this QoS Flow is for the URLLC service.

In step 302, the SMF may determine whether the existing QoS flow as well as the new QoS flow in step 301 is a service for URLLC service through information such as authorized 5QI, NG-RAN node capability and operator configuration. In addition, it is possible to determine whether to perform reliable transmission based on the determination result. That is, when the new Qos Flow or the existing Qos Flow is a service for the URLLC service, it is decided to perform reliable transmission, and when it is not a service for the URLLC service, it is decided not to perform the reliable transmission. can

In step 303, if the SMF determines not to perform reliable transmission in step 302, the Always-on PDU Session Granted indication may not be included in the PDU Session Modification Command message.

In step 304, if the SMF decides to perform reliable transmission in step 302, it can be checked whether the PDU Session currently transmitting the corresponding QoS Flow is an Always-on PDU Session.

In step 305, if the PDU Session currently transmitting the corresponding QoS Flow in step 304 is not an Always-on PDU Session, an Always-on PDU Session Granted indication may be included in the PDU Session Modification Command message. The SMF may inform the UE that the corresponding PDU Session has been changed to the Always-on PDU Session through the Always-on PDU session Granted indication parameter. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, UP connection activation of the corresponding PDU Session must be requested. That is, in procedures such as Registration or Service Request, the UE may include the ID of the corresponding PDU Session in the List Of PDU Sessions To Be Activated parameter.

In step 306, if the PDU Session currently transmitting the corresponding QoS Flow in step 304 is not an Always-on PDU Session, the Always-on PDU Session Granted indication may not be included in the PDU Session Modification Command message.

4 is a flow chart showing the operation of the SMF when the QoS Flow is released according to an embodiment of the present disclosure. For purposes of illustration, each step disclosed in FIG. 4 will be described below as being performed by itself by the SMF, but this does not limit the scope of the present disclosure, and any steps that can be performed by a person skilled in the art to which the present disclosure pertains may be performed according to an embodiment of the present invention, for example, may be performed by any configuration provided to perform each step according to the request of the SMF.

In step 401, when the QoS Flow is released, the SMF may determine whether the corresponding QoS Flow is for the URLLC service.

In step 402, the SMF may determine whether the existing QoS flow no longer supports the URLLC service as well as the released QoS flow in step 401 through information such as authorized 5QI, NG-RAN node capability, and operator configuration. In addition, it is possible to determine whether to perform reliable transmission based on the determination result. That is, when the released Qos Flow or the existing Qos Flow no longer supports the URLLC service, it is decided not to perform the reliable transmission, and when the URLLC service is supported, the reliable transmission is performed. may decide to do so.

In step 403, if the QoS Flow released in step 402 is not a QoS Flow for URLLC service, or if there is no change in the existing QoS Flow to support URLLC service, that is, if at least one QoS Flow still supports URLLC service , the Always-on PDU Session Release Granted indication may not be included in the PDU Session Modification Command message.

In step 404, if the QoS flow released in step 402 is a QoS flow for URLLC service or if the existing QoS flow does not support the URLLC service, that is, if no QoS flow supports the URLLC service, the SMF You can check whether the PDU Session is created as an Always-on PDU Session for any reason other than the URLLC service.

In step 405, if the current PDU Session is not created as an Always-on PDU Session for reasons other than the URLLC service in step 404, the Always-on PDU Session Release Granted indication may be included in the PDU Session Modification Command message. The SMF may inform the UE that the Always-on PDU Session has been changed to the PDU Session through the Always-on PDU Session Release Granted indication parameter. This is because when the UE transitions from the CM-IDLE state to the CM-CONNECTED state, it requests UP connection activation of the corresponding PDU Session, so it is necessary to notify the UE to stop it. That is, in procedures such as Registration or Service Request, the UE may stop including the ID of the PDU Session in the List Of PDU Sessions To Be Activated parameter.

In step 406, if the current PDU Session is not created as an Always-on PDU Session for any reason other than the URLLC service in step 404, the Always-on PDU Session Release Granted indication may not be included in the PDU Session Modification Command message.

5 is a flow chart illustrating an operation of a UE when a new QoS Flow is generated according to an embodiment of the present disclosure. For purposes of illustration, each step disclosed in FIG. 5 will be described below as being performed by the UE itself, but this does not limit the scope of the present disclosure, and any steps that can be performed by a person skilled in the art to which the present disclosure pertains may be carried out according to an embodiment of the present invention, for example, may be performed by any configuration provided to perform each step according to the request of the UE.

In step 501, when a new QoS Flow is generated, the UE may determine whether this QoS Flow is for the URLLC service.

In step 502, the UE may receive from a higher layer whether the new QoS flow and the existing QoS flow in step 501 are services for the URLLC service.

In step 503, if the new QoS Flow and the existing QoS Flow are not QoS Flows for the URLLC service in step 502, the UE may not include an Always-on PDU Session Requested indication in the PDU Session Modification Request message.

In step 504, if the new QoS flow or the existing QoS flow is the QoS flow for the URLLC service in step 502, the UE may check whether the PDU Session currently transmitting the corresponding QoS Flow is an Always-on PDU Session.

In step 505, if the PDU Session currently transmitting the corresponding QoS Flow in step 504 is not an Always-on PDU Session, the UE may include an Always-on PDU Session Requested indication in the PDU Session Modification Request message.

In step 506, if the PDU Session currently transmitting the corresponding QoS Flow in step 504 is an Always-on PDU Session, the Always-on PDU Session Requested indication may not be included in the PDU Session Modification Request message.

6 is a flow chart illustrating an operation of a UE when QoS Flow is released according to an embodiment of the present disclosure. For purposes of illustration, each step disclosed in FIG. 6 will be described below as being performed by the UE itself, but this does not limit the scope of the present disclosure, and any steps that can be performed by a person skilled in the art to which the present disclosure pertains may be carried out according to an embodiment of the present invention, for example, may be performed by any configuration provided to perform each step according to the request of the UE.

In step 601, when the QoS Flow is released, the UE may determine whether the corresponding QoS Flow is for the URLLC service.

In step 602, the UE may receive from a higher layer whether the existing QoS flow no longer supports the URLLC service as well as the QoS flow released in step 601.

In step 603, if the QoS Flow released in step 602 is not a QoS Flow for URLLC service, or if the existing QoS Flow does not change the URLLC service support, that is, if at least one QoS Flow still supports the URLLC service, The Always-on PDU Session Release Requested indication may not be included in the PDU Session Modification Request message.

In step 604, if the QoS Flow released in step 602 is a QoS flow for URLLC service or if the existing QoS flow does not support URLLC service, that is, if no QoS flow supports URLLC service, the UE You can check whether the PDU Session is created as an Always-on PDU Session for any reason other than the URLLC service.

In step 605, if the current PDU Session is not created as an Always-on PDU Session for any reason other than the URLLC service in step 604, the Always-on PDU Session Release Requested indication may be included in the PDU Session Modification Request message.

In step 606, if the current PDU Session is not created as an Always-on PDU Session for reasons other than the URLLC service in step 604, the Always-on PDU Session Release Requested indication may not be included in the PDU Session Modification Request message.

Methods according to the embodiments described in the claims or specifications 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 the computer-readable storage medium are configured to be executable by one or more processors in an electronic device (device). One or more programs include instructions for causing an electronic device to execute methods according to embodiments described in a claim 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), electrically erasable programmable ROM (electrically erasable programmable read only memory, EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs), or other It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all thereof. In addition, each configuration memory may be included in plurality.

In addition, the program is transmitted through a communication network consisting of a communication network such as the Internet, intranet, local area network (LAN), wide area network (WAN), or storage area network (SAN), or a combination thereof It may be stored on an attachable storage device that can be accessed. Such a storage device may be connected to a device implementing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may be connected to the device implementing the embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, components included in the disclosure are expressed in the singular or plural according to the specific embodiments presented. However, the singular or plural expression is appropriately selected for the context presented for convenience of description, and the present disclosure is not limited to the singular or plural element, and even if the element is expressed in plural, it is composed of the singular or singular. Even an expressed component may be composed of a plurality of components.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments and should be defined by the claims described below as well as the claims and equivalents.

Claims (1)

A control signal processing method in a wireless communication system, comprising:
receiving a first control signal transmitted from a base station;
processing the received first control signal; and
and transmitting a second control signal generated based on the processing to the base station.

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