CN115334692A

CN115334692A - Method and equipment used for wireless communication

Info

Publication number: CN115334692A
Application number: CN202110451961.4A
Authority: CN
Inventors: 陈宇; 张晓博
Original assignee: Shanghai Langbo Communication Technology Co Ltd
Current assignee: Shanghai Langbo Communication Technology Co Ltd
Priority date: 2021-04-26
Filing date: 2021-04-26
Publication date: 2022-11-11

Abstract

The application discloses a method and apparatus used for wireless communication, comprising: receiving a first message; re-establishing the first PDCP entity in response to receiving the first message; transmitting a first PDCP PDU generated by the first PDCP entity; wherein the first PDCP PDU includes a first field and data, the first message being used to set the first field of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU is generated after a re-establishment of the first PDCP entity. The reliability is improved and chaos is avoided through the first message.

Description

Method and equipment used for wireless communication

Technical Field

The present application relates to a transmission method and apparatus in a wireless communication system, and more particularly, to a method and apparatus for reducing service interruption, improving service continuity, enhancing reliability, and improving security in wireless communication.

Background

Application scenes of a future wireless communication system are more diversified, and different application scenes put different performance requirements on the system. In order to meet different performance requirements of various application scenarios, research on New air interface technology (NR) or Fifth Generation (5G) is decided on 3GPP (3 rd Generation Partner Project) RAN (Radio Access Network) #72 conventions, and Work on NR is started on WI (Work Item) that has passed NR on 3GPP RAN #75 conventions.

In Communication, both LTE (Long Term Evolution) and 5G NR relate to accurate reception of Reliable information, optimized energy efficiency ratio, determination of information validity, flexible resource allocation, scalable system structure, efficient non-access stratum information processing, lower service interruption and dropped rate, support for Low power consumption, which is important for normal Communication between a base station and user equipment, reasonable scheduling of resources, and balancing of system load, so to speak, high throughput rate, meet Communication requirements of various services, improve spectrum utilization, improve service quality, and are essential for eMBB (enhanced Mobile BroadBand), URLLC (Ultra Low Latency Communication), eMTC (enhanced Machine Type Communication) or eMTC (enhanced Machine Type Communication). Meanwhile, in the Internet of Things in the field of industry, in V2X (Vehicular to X), communication between devices (Device to Device) is performed, in communication of unlicensed spectrum, in user communication quality monitoring, network planning optimization, in NTN (Non-terrestrial Network communication), in TN (terrestrial Network communication), in Dual connectivity (Dual connectivity) system, in wireless resource management and codebook selection of multiple antennas, there are wide requirements in signaling design, neighborhood management, service management, and beamforming, and the transmission mode of information is divided into broadcast and unicast, and both transmission modes are indispensable for the 5G system, because they help to meet the above requirements.

With the continuous increase of the scenes and the complexity of the system, higher requirements are put forward on the reduction of the interruption rate, the reduction of the time delay, the enhancement of the reliability, the enhancement of the stability of the system, the flexibility of the service and the saving of the power, and meanwhile, the compatibility among different versions of different systems needs to be considered when the system is designed.

Disclosure of Invention

In many communication scenarios, establishment and reconstruction of an entity and a link may be involved, and particularly, in the case of key update, reconstruction of the relevant entity is required to ensure security. When ciphering is performed by the PDCP entity, the PDCP entity concerned is re-established. In scenarios involving relaying, when communication between UEs, especially relay node to UE, is involved, problems of distributed control and control delay may occur. For example, re-establishment involving PDCP may also involve the RLC entity with which it is associated, but in the relaying scenario the PDCP entity and the RLC entity may not be in the same node, resulting in the two entities being potentially out of synchronization if re-establishment is to take place. When the PDCP entity uses the old key for ciphering before re-establishment and uses the new key for ciphering after re-establishment, due to the separation of the PDCP entity and the RLC entity, the receiving end may receive data ciphered using the old key even after the PDCP entity is re-established, thereby causing a deciphering error, causing communication failure or increasing the packet error rate of the application layer. The method and the device indicate whether the data is generated before or after the related PDCP entity is rebuilt through the first domain in the PDCP PDU, so that the receiving end can be helped to correctly distinguish the data and decrypt the data by using a correct key.

In view of the above, the present application provides a solution.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments in any node of the present application may be applied to any other node. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

The application discloses a method in a first node used for wireless communication, comprising:

receiving a first message; re-establishing the first PDCP entity in response to receiving the first message;

transmitting a first PDCP PDU generated by the first PDCP entity;

wherein the first PDCP PDU includes a first field and data, the first message being used to set the first field of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU is generated after a re-establishment of the first PDCP entity.

As an embodiment, the problem to be solved by the present application includes: in scenarios where communication between UEs is required, for example, when communication is performed by sidelink technique, especially when layer 2 relay architecture is used, a PDCP entity may be separated from (part or all of) associated RLC entities. This is very likely to cause confusion at the receiving end during the PDCP entity re-establishment process, because the relay node buffers an indefinite amount of data, which is generated before the PDCP entity re-establishment but is transmitted after the PDCP entity re-establishment. In a conventional scenario, the PDCP entity and the associated RLC entity are in the same node, and they may be re-established at the same time, and the RLC entity may be cleared of data during re-establishment. The present application avoids possible collisions by the indication of the first field of the PDCP PDU.

As an example, the benefits of the above method include: the method proposed by the present application can solve the above problems. Even if the receiving end receives the data generated by encrypting the old key, the data can be correctly identified, or the data can be decrypted by using the old key or discarded, and no confusion is caused in any way. On the other hand, the method and the device are beneficial to reducing the complexity of the relay node, and even if a plurality of hops exist, a plurality of relays participate, so that the problem can not be caused.

As an example, the peculiarities of the present application include: the PDU is a Protocol Data Unit (Protocol Data Unit).

Specifically, according to an aspect of the present invention, the act of sending the first PDCP PDU includes: sending a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN; wherein the first message is not used to reset the first RLC SN.

Specifically, according to one aspect of the invention, a second message is sent;

wherein the behavior re-establishing the first PDCP entity comprises: re-establishing a first RLC entity, the first RLC entity being associated with the first PDCP entity; the second message indicates that the first RLC entity is re-established.

Specifically, according to an aspect of the present invention, a first report is transmitted, the first report indicating that the second PDCP SDU is not received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

Specifically, according to an aspect of the present invention, a first report is transmitted, the first report indicating that the second PDCP SDU is not received by indicating a fourth sequence number; the PDCP sequence number assigned to the second PDCP SDU before the first PDCP entity is re-established is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

Specifically, according to an aspect of the present invention, a second report is received, the second report being used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being non-0.

Specifically, according to an aspect of the present invention, the first message is used to indicate a first key used by the first PDCP entity to cipher the data included in the first PDCP PDU.

Specifically, according to an aspect of the present application, the first node is a user equipment.

Specifically, according to an aspect of the present application, the first node is an internet of things terminal.

In particular, according to an aspect of the present application, the first node is a relay.

Specifically, according to an aspect of the present application, the first node is a vehicle-mounted terminal.

In particular, according to one aspect of the application, the first node is an aircraft.

The application discloses a method in a second node used for wireless communication, comprising:

sending a first message; the first message is used to trigger re-establishing a first PDCP entity;

receiving a first PDCP PDU generated by the first PDCP entity;

wherein the first PDCP PDU includes a first domain and data, and the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

Specifically, according to an aspect of the present invention, the act of receiving the first PDCP PDU comprises:

receiving a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN; wherein the first message is not used to reset the first RLC SN.

Specifically, according to an aspect of the present invention, a first report is received, the first report indicating that a second PDCP SDU is not received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

Specifically, according to an aspect of the present invention, a first report is received, the first report indicating that the second PDCP SDU is not received by indicating a fourth sequence number; the PDCP sequence number assigned to the second PDCP SDU before the first PDCP entity is re-established is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

Specifically, according to an aspect of the present invention, a second report is transmitted, the second report being used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being non-0.

Specifically, according to an aspect of the present invention, the first message is used to indicate a first key, and the first PDCP entity encrypts the data included in the first PDCP PDU using the first key.

Specifically, according to an aspect of the present application, the first node is a relay.

A first node used for wireless communication, comprising:

a first receiver to receive a first message; re-establishing the first PDCP entity in response to receiving the first message;

a first transmitter to transmit a first PDCP PDU generated by the first PDCP entity;

The application discloses a second node used for wireless communication, comprising:

a second transmitter for transmitting the first message; the first message is used to trigger re-establishing a first PDCP entity;

a second receiver which receives a first PDCP PDU generated by the first PDCP entity;

As an example, compared with the conventional scheme, the present application has the following advantages: in the method provided by the application, due to the reasons of key updating and the like, the PDCP entity is rebuilt, and a new key is required to be used before and after the rebuilding; when the RLC entity and the PDCP entity are separated logically or physically and cannot be reestablished at the same time, the method provided by the application can prevent the receiving end from receiving the data encrypted by the old key without self-knowledge.

As an example, compared with the conventional scheme, the method has the following advantages: when one RLC entity associated with the PDCP entity is in the relay node, the relay node may multiplex data of a plurality of channels or a plurality of UEs on an RLC bearer corresponding to the same RLC entity, and when one RLC entity associated with the RLC entity needs to be re-established, the method provided by the present application does not need to re-establish the RLC entity, thereby reducing the influence on other channels or other users.

As an example, compared with the conventional scheme, the method has the following advantages: for a DRB, the RLC entity generally needs to be re-established when RRC connection is continued or first re-configuration after RRC re-establishment occurs, and if the RLC entity is in a relay node and some services already exist, re-establishment may affect the existing services.

As an example, compared with the conventional scheme, the method has the following advantages: when a PDCP entity corresponding to a bearer of a Uu interface is associated with an RLC entity of a PC5 interface, the re-establishment of the PDCP entity of the Uu interface may trigger the re-establishment of the RLC entity of the PC5 interface. This helps to reduce the time delay of the PC5 interface and the Uu interface, and improves the resource utilization efficiency.

As an example, compared with the conventional scheme, the method has the following advantages: the existing PDCP header format can be utilized without adding additional bits and thus without adding additional overhead.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of the non-limiting embodiments with reference to the following drawings in which:

FIG. 1 illustrates a flow chart of receiving a first message and transmitting a first PDCP PDU according to one embodiment of the present application;

FIG. 2 shows a schematic diagram of a network architecture according to an embodiment of the present application;

figure 3 shows a schematic diagram of an embodiment of a radio protocol architecture for the user plane and the control plane according to an embodiment of the present application;

FIG. 4 shows a schematic diagram of a first node, a second node, according to an embodiment of the present application;

FIG. 5 shows a flow diagram of a transmission according to an embodiment of the present application;

FIG. 6 shows a flow diagram of a transmission according to an embodiment of the application;

FIG. 7 illustrates a schematic diagram of PDCP PDUs according to an embodiment of the present application;

figure 8 shows a schematic diagram of a protocol stack for layer 2 relaying according to an embodiment of the present application;

FIG. 9 illustrates a diagram where a first message is used to set a first domain of a first PDCP PDU, according to an embodiment of the present application;

FIG. 10 shows a schematic diagram of a first message not being used to reset a first RLC SN according to one embodiment of the present application;

FIG. 11 illustrates a diagram where a second sequence number is used to determine a fourth sequence number according to one embodiment of the application;

FIG. 12 illustrates a diagram where a first COUNT value is used to determine a first initial value according to one embodiment of the present application;

figure 13 illustrates a schematic diagram of a processing apparatus for use in a first node according to one embodiment of the present application;

figure 14 illustrates a schematic diagram of a processing arrangement for use in a second node according to an embodiment of the present application;

Detailed Description

The technical solutions of the present application will be further described in detail with reference to the accompanying drawings, and it should be noted that the embodiments and features of the embodiments in the present application can be arbitrarily combined with each other without conflict.

Example 1

Embodiment 1 illustrates a flow chart of receiving a first message and transmitting a first PDCP PDU according to an embodiment of the present application, as shown in fig. 1. In fig. 1, each block represents a step, and it is particularly emphasized that the sequence of the blocks in the figure does not represent a chronological relationship between the represented steps.

In embodiment 1, a first node in the present application receives a first message in step 101; transmitting a first PDCP PDU in step 102;

wherein the first node re-establishes the first PDCP entity in response to receiving the first message; the first PDCP PDU is generated by the first PDCP entity; the first PDCP PDU includes a first domain and data, the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the first node is a UE (User Equipment).

As one embodiment, AS (Access Stratum) security of the first node is activated.

As an embodiment, the first message is an RRC (Radio Resource Control) message.

As an embodiment, the first message is transmitted over a Uu interface.

As an embodiment, the first message is transmitted through an SRB of the Uu interface.

As an embodiment, the first message comprises rrcreeconfiguration.

For one embodiment, the first message comprises an RRCConnectionReconfiguration.

For one embodiment, the first message includes RRCResume.

For one embodiment, the first message includes rrcconnectionresponse.

For one embodiment, the first message includes an RLC-BearerConfig.

As an embodiment, the first message does not include RLC-BearerConfig.

As an embodiment, the first message comprises a cellgroupConfig.

As an embodiment, the first message does not comprise cellgroupConfig.

As one embodiment, the first message includes a radioBearerConfig.

As an embodiment, the first message comprises a radioBearerConfig2.

As one embodiment, the first message comprises drb-ToAddModList.

For one embodiment, the first message includes a PDCP-Config.

In one embodiment, the first message includes resestoplishpdcp and resestoplishpdcp is set to true.

For one embodiment, the first message includes a keyToUse, and the key indicated by the keyToUse is changed from the key in the configuration stored by the first node.

For one embodiment, the first message is a NAS (non-Access Stratum) message.

For one embodiment, the first message comprises a SECURITY MODE COMMAND.

For one embodiment, the first message comprises a PDU SESSION MODIFICATION COMMAND.

For one embodiment, the first message includes an AUTHENTICATION REQUEST.

For one embodiment, the first message includes an authencationrequest.

For one embodiment, the first message includes a REGISTRATION ACCEPT.

For one embodiment, the first message includes SERVICE ACCEPT.

For one embodiment, the first message comprises a CONFIGURATION UPDATE COMMAND.

As one embodiment, the first message includes higher layer signaling.

For one embodiment, the first message comprises a PDCP status report message.

As an embodiment, the Physical channel occupied by the first message includes PSCCH (Physical sidelink control channel) channel transmission.

As an embodiment, the Physical channel occupied by the first message includes a PSSCH (Physical sidelink shared channel) channel transmission.

As an embodiment, the Physical channel occupied by the first message includes a PDSCH (Physical downlink Shared channel) channel transmission.

As an embodiment, the first message is transmitted over a sidelink.

As one embodiment, the first message is used to configure a DRB (Data RB).

As an embodiment, the first message is used to configure an RB (Radio Bearer).

As an embodiment, the first message is used to configure an SLRB (Sidelink RB).

As an embodiment, the first message is used to indicate that the first field of the first PDCP PDU is set to a first initial value.

For one embodiment, the first domain includes PDCP SNs, and the first initial value is configurable.

As a sub-embodiment of the above embodiment, the first message is used to set a first state variable, which is used to calculate the first initial value.

As a sub-embodiment of the above embodiment, the first initial value is not 0.

As a sub-embodiment of the above embodiment, the first initial value is a positive number.

As a sub-embodiment of the above embodiment, the first initial value relates to a COUNT value associated with the first PDCP PDU.

As a sub-embodiment of the above embodiment, the first initial value relates to a COUNT value associated with a PDCP SDU carried by the first PDCP PDU.

As an embodiment, the first field comprises at least one R, each R occupying 1 bit.

As a sub-embodiment of the above embodiment, the first field of the first PDCP PDU indicates a number of times the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the first field of the first PDCP PDU is equal to a remainder of the number of times the first PDCP entity is reconstructed modulo Q, Q being Q1 to the power of 2, Q1 being the number of R included in the first field.

As an embodiment, the first message explicitly indicates the first initial value.

As an embodiment, the first message implicitly indicates the first initial value.

As one embodiment, the first field includes a PDCP SN, and the first message is used to indicate that the first field of the first PDCP PDU is set to a first initial value.

As an embodiment, the first PDCP entity corresponds to a radio bearer of a PC5 interface.

As an embodiment, the first PDCP entity is a transmitting PDCP entity.

As an embodiment, the first PDCP entity is a receiving PDCP entity.

As an embodiment, after the first PDCP entity is re-established, all PDCP PDUs of data types sent until the next re-establishment include the first field, and the values of the first field are the same.

As an embodiment, after the first PDCP entity is re-established, all the PDCP PDUs of the data type sent until the next re-establishment include the first field, and the value of the first field changes one by one.

As a sub-embodiment of the above embodiment, the value of the first domain is changed cyclically, and each time the first PDCP entity generates a PDCP PDU of a data type, the value of the first domain is increased by 1 until the maximum value that can be represented by the first domain is reached, and then the operation starts from 0 again.

As an embodiment, a header of the first PDCP PDU includes the first field.

In one embodiment, the first PDCP PDU is a data type PDCP PDU.

As an embodiment, the first PDCP entity corresponds to a first radio bearer.

As an embodiment, the first radio bearer is a radio bearer of a Uu interface.

As an embodiment, the act of transmitting the first PDCP PDU is performed after the act of re-establishing the first PDCP entity.

As an embodiment, the first PDCP PDU is a first PDCP PDU generated by the first PDCP entity after the behavior re-establishes the first PDCP entity.

As one embodiment, the first radio bearer is an AM DRB.

As one embodiment, the first radio bearer is an UM DRB.

As one embodiment, the first radio bearer is configured with ciphering.

As one embodiment, the first radio bearer is not configured with integrity protection.

As an embodiment, the first PDCP PDU does not use integrity protection.

As an embodiment, the first RLC entity generates a first RLC PDU according to the first PDCP PDU.

As an embodiment, the radio bearer used by the first PDCP PDU is the first radio bearer.

As an embodiment, the first message is used to indicate a first key used by the first PDCP entity to cipher the data included in the first PDCP PDU;

as a sub-embodiment of this embodiment, the first key comprises K _AMF ；

As a sub-embodiment of this embodiment, the first key comprises K _gNB ；

As a sub-embodiment of this embodiment, the first key comprises K _UP-enc ；

As a sub-embodiment of this embodiment, the data included in the first PDCP PDU is a PDCP SDU;

as a sub-embodiment of this embodiment, the data included in the first PDCP PDU includes an IP packet;

as a sub-embodiment of this embodiment, the data included in the first PDCP PDU includes non-IP data;

as a sub-embodiment of this embodiment, the data included in the first PDCP PDU includes non-3 GPP data;

as a sub-embodiment of this embodiment, the Data included in the first PDCP PDU is Data of the first PDCP PDU;

as a sub-embodiment of this embodiment, a ciphering algorithm for ciphering the data of the first PDCP PDU includes 128-NEA1 and 128-NIA1.

As a sub-embodiment of this embodiment, a ciphering algorithm used for ciphering the data of the first PDCP PDU includes 128-NEA2 and 128-NIA2.

As a sub-embodiment of this embodiment, a ciphering algorithm for ciphering the data of the first PDCP PDU includes 128-NEA3 and 128-NIA3.

As a sub-embodiment of this embodiment, a ciphering algorithm used for ciphering the data of the first PDCP PDU includes 128-EEA1 and 128-EIA1.

As a sub-embodiment of this embodiment, a ciphering algorithm used for ciphering the data of the first PDCP PDU includes 128-EEA2 and 128-EIA2.

As a sub-embodiment of this embodiment, a ciphering algorithm for ciphering the data of the first PDCP PDU includes 128-EEA3 and 128-EIA3.

As a sub-embodiment of this embodiment, a ciphering algorithm for ciphering the data of the first PDCP PDU includes SNOW.

As a sub-embodiment of this embodiment, a ciphering algorithm used for ciphering of the data of the first PDCP PDU includes AES.

As a sub-embodiment of this embodiment, a ciphering algorithm used for ciphering of the data of the first PDCP PDU includes ZUC.

As an embodiment, the first message indicates a keysetthangeindicator, which is used to generate the first key.

As an embodiment, the first message directly explicitly indicates the first key.

As one embodiment, the first message indicates a parameter for generating the first key.

As an embodiment, the first message indicates that the first key needs to be generated, and the first node generates the first key according to a configured or pre-agreed parameter.

As an embodiment, the first message indicates nextHopChainingCount, which is used to generate the first key.

As one embodiment, the first message indicates a sk-counter that is used to generate the first key.

As an embodiment, the first message is used to reset a key (re-key).

As an embodiment, the first message is used for rekey refresh (key refresh).

AS one embodiment, AS security of the first node is activated.

As one embodiment, the first message indicates a full configuration.

As an embodiment, the first message is used to trigger re-establishing the first PDCP entity.

As an embodiment, the first message indicates to re-establish the first PDCP entity.

As an embodiment, reestablishment of the first PDCP entity occurs after the first message is executed.

As an embodiment, the first message is executed or applied, resulting in the first PDCP entity being re-established (re-establishment).

As an embodiment, the act of re-establishing the first PDCP entity comprises: the upstream header compression protocol is reset (reset) and restarted in the IR state of U-mode.

As an embodiment, the act of re-establishing the first PDCP entity comprises: the EHC upstream header compression protocol is reset (reset).

As an embodiment, the behavior re-establishing the first PDCP entity comprises: TX _ NEXT is set to an initial value.

As an embodiment, the act of re-establishing the first PDCP entity comprises: setting TX _ NEXT to the first initial value.

As an embodiment, the behavior re-establishing the first PDCP entity comprises: the ciphering algorithm and key provided by the higher layer in the PDCP entity re-establishment procedure are applied.

As an embodiment, the act of re-establishing the first PDCP entity comprises: for each PDCP SDU associated with a PDCP SN, for which the corresponding PDCP PDU has not yet been submitted to the lower layer, the PDCP SDUs are considered as received from the higher layer, transmission is performed for the PDCP SDUs in the order of the COUNT values respectively associated with the PDCP SDUs determined before the first PDCP entity is re-established, and there is no need to restart the discard timer.

As an embodiment, the act of re-establishing the first PDCP entity comprises: for each PDCP SDU associated with a PDCP SN, for which the corresponding PDCP PDU has not been acknowledged by the lower layer and the bearer corresponding to the first PDCP entity is suspended, considering that the PDCP SDUs are received from the higher layer, transmitting the PDCP SDUs in the order of the COUNT values respectively associated with the PDCP SDUs determined before the first PDCP entity is re-established, and without restarting the discard timer.

As an embodiment, the act of re-establishing the first PDCP entity comprises: performing a retransmission or transmission for all PDCP SDUs for which a PDCP SN has been associated, starting from the first PDCP SDU for which its corresponding PDCP data PDU has not been acknowledged by the lower layer, the order of transmission being determined according to the COUNT value associated with these PDCP SDUs before said first PDCP entity is re-established;

as a sub-embodiment of this embodiment, ROHC is used and/or header compression is performed on the PDCP SDUs;

as a sub-embodiment of this embodiment, the PDCP SDUs are ciphered using COUNT values associated with the PDCP SDUs;

as a sub-embodiment of this embodiment, PDCP PDUs generated by these PDCP SDUs are submitted to a lower layer.

As an embodiment, the behavior re-establishing the first PDCP entity comprises: the PDCP data PDUs received from the lower layer due to the lower layer re-establishment are processed.

As an embodiment, the act of re-establishing the first PDCP entity comprises: stopping and resetting the t-Reordering timer; after header decompression, all buffered PDCP SDUs are sent to higher layers according to the associated COUNT value.

As an embodiment, the act of re-establishing the first PDCP entity comprises: header decompression is performed using ROHC.

As an embodiment, the behavior re-establishing the first PDCP entity comprises: header decompression is performed using EHC.

As an embodiment, the act of re-establishing the first PDCP entity comprises: and resetting the ROHC protocol and entering the NC state of the U mode aiming at the ROHC protocol.

As an embodiment, the act of re-establishing the first PDCP entity comprises: the EHC protocol is reset.

As an embodiment, the behavior re-establishing the first PDCP entity comprises: RX _ NEXT and RX _ DELIV are set to initial values.

As a sub-embodiment of this embodiment, the initial value is the first initial value.

As an embodiment, the first message explicitly sets the first field of the first PDCP PDU.

As an embodiment, the first PDCP entity is a generator of the first PDCP PDU.

As an embodiment, the first PDCP PDU includes the first field and data, and the data is a PDCP SDU.

As an embodiment, the first PDCP PDU includes the first field and data, and the data is an IP packet.

In one embodiment, the first PDCP PDU includes the first field and data, and the data is an SDAP PDU.

As an embodiment, the first PDCP PDU includes the first field and data, and the data is a non-IP packet.

As an embodiment, the first PDCP PDU includes the first field and data, and the data is payload of the first PDCP PDU.

As an embodiment, the first PDCP PDU carries a first PDCP SDU; one PDCP PDU carries only one PDCP SDU.

As a sub-embodiment of this embodiment, the PDCP SDU is received before the action reconstructs the first PDCP entity, and a PDCP PDU corresponding to the first PDCP SDU is not submitted to a lower layer before the action reconstructs the first PDCP entity;

as a sub-embodiment of this embodiment, the PDCP SDU is received before the behavior reconstructs the first PDCP entity, and a PDCP PDU corresponding to the first PDCP SDU is not acknowledged by a lower layer before the behavior reconstructs the first PDCP entity;

as a sub-embodiment of this embodiment, the PDCP SDU is received before the action reconstructs the first PDCP entity and is associated with a PDCP SN, and the PDCP PDU corresponding to the first PDCP SDU is not submitted to the lower layer before the action reconstructs the first PDCP entity;

as a sub-embodiment of this embodiment, the PDCP SDU is received after the act of re-establishing the first PDCP entity.

As an embodiment, the first PDCP PDU is generated using parameters after the first PDCP entity is re-established.

As an embodiment, a header of the first PDCP PDU is generated or determined by a state variable after the first PDCP entity is re-established.

As an embodiment, the transmission or retransmission of the first PDCP PDU occurs after the first PDCP entity is re-established.

As an embodiment, the transmission related state variable of the first PDCP entity is reset and set to an initial value during the PDCP entity re-establishment procedure, the reception related state variable of the first PDCP entity is not reset during the PDCP entity re-establishment procedure, and the reception related state variable of the first PDCP entity is reset and set to an initial value after the PDCP entity is re-established and one PDCP PDU is received.

As a sub-embodiment of the above embodiment, the first message is used to indicate an initial value of the transmission related state variable.

As a sub-embodiment of the above embodiment, the first message is used to indicate an initial value of the reception-related state variable.

As a sub-embodiment of the above embodiment, the receiving related status variable of the first PDCP entity is generated after the PDCP entity is re-established and the first field receiving the one PDCP PDU indicates that the one PDCP PDU is a corresponding PDCP entity re-established.

As an embodiment, the transmit-related state variable of the first PDCP entity is reset and set to an initial value during the PDCP entity re-establishment procedure, the receive-related state variable of the first PDCP entity is not reset during the PDCP entity re-establishment procedure, the re-establishment of the first PDCP entity includes starting a first timer, and the receive-related state variable of the first PDCP entity is reset and set to an initial value after the first timer expires.

As a sub-embodiment of the above embodiment, the first timer is predefined, e.g. 100ms.

As a sub-embodiment of the above embodiment, the first timer is indicated by the first message.

As a sub-embodiment of the above embodiment, the first message is used to indicate an initial value of the state variable related to transmission.

As an embodiment, the sending related state variables are reset in re-establishment to help to perform re-establishment quickly, and the receiving related state variables are reset later to help to receive data sent before re-establishment but buffered in RLC.

Example 2

Embodiment 2 illustrates a schematic diagram of a network architecture according to an embodiment of the present application, as shown in fig. 2. Fig. 2 illustrates a V2X communication architecture under a 5G NR (new radio, new air interface), LTE (Long-Term Evolution), and LTE-a (Long-Term Evolution Advanced, enhanced Long-Term Evolution) system architecture. The 5G NR or LTE network architecture may be referred to as 5GS (5 GSystem)/EPS (Evolved Packet System) or some other suitable terminology.

The V2X communication architecture of embodiment 2 includes UE (User Equipment) 201, ue241, ng-RAN (next generation radio access network) 202,5gc (5G Core network )/EPC (Evolved Packet Core) 210, hss (Home Subscriber Server )/UDM (Unified Data Management) 220, proSe function 250, and ProSe application Server 230. The V2X communication architecture may interconnect with other access networks, but these entities/interfaces are not shown for simplicity. As shown, the V2X communication architecture provides packet switched services, however those skilled in the art will readily appreciate that the various concepts presented throughout this application may be extended to networks providing circuit switched services or other cellular networks. The NG-RAN includes NR node bs (gnbs) 203 and other gnbs 204. The gNB203 provides user and control plane protocol termination towards the UE 201. The gnbs 203 may be connected to other gnbs 204 via an Xn interface (e.g., backhaul). The gNB203 may also be referred to as a base station, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a Basic Service Set (BSS), an Extended Service Set (ESS), a TRP (transmitting receiving node), or some other suitable terminology. The gNB203 provides the UE201 with an access point to the 5GC/EPC210. Examples of the UE201 include a cellular phone, a smart phone, a Session Initiation Protocol (SIP) phone, a laptop, a Personal Digital Assistant (PDA), a satellite radio, non-terrestrial base station communications, satellite mobile communications, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player), a camera, a game console, a drone, an aircraft, a narrowband internet of things device, a machine type communication device, a terrestrial vehicle, an automobile, a wearable device, or any other similar functioning device. UE201 may also be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. The gNB203 is connected to the 5GC/EPC210 through an S1/NG interface. The 5GC/EPC210 includes MME (Mobility Management Entity)/AMF (Authentication Management Field)/SMF (Session Management Function) 211, other MME/AMF/SMF214, S-GW (serving Gateway)/UPF (user plane Function) 212, and P-GW (Packet data Network Gateway)/UPF 213. The MME/AMF/SMF211 is a control node that handles signaling between the UE201 and the 5GC/EPC210. In general, the MME/AMF/SMF211 provides bearer and connection management. All user IP (Internet protocol) packets are transported through the S-GW/UPF212, and the S-GW/UPF212 itself is connected to the P-GW/UPF213. The P-GW provides UE IP address allocation as well as other functions. The P-GW/UPF213 is connected to the internet service 230. The internet service 230 includes an operator-corresponding internet protocol service, and may specifically include the internet, an intranet, an IMS (IP Multimedia Subsystem), and a packet-switched streaming service. The ProSe function 250 is a logical function for network-related behavior required for location-based services (ProSe); including a DPF (Direct Provisioning Function), a Direct Discovery Name Management Function (Direct Discovery Name Management Function), an EPC-level Discovery ProSe Function (EPC-level Discovery ProSe Function), and the like. The ProSe application server 230 has functions of storing EPC ProSe subscriber identities, mapping between application layer subscriber identities and EPC ProSe subscriber identities, allocating a pool of code suffixes restricted by ProSe, and the like.

As an embodiment, the UE201 and the UE241 are connected through a PC5 Reference Point (Reference Point).

As an embodiment, the ProSe function 250 is connected with the UE201 and the UE241 through PC3 reference points, respectively.

As an embodiment, the ProSe function 250 is connected with the ProSe application server 230 through a PC2 reference point.

As an embodiment, the ProSe application server 230 is connected to the ProSe application of the UE201 and the ProSe application of the UE241 through a PC1 reference point, respectively.

As an embodiment, the second node, the first node and the third node in the present application are NR node B, UE201 and UE241, respectively.

As an embodiment, the first node and the second node in the present application are UE201 and UE241, respectively.

As an embodiment, the first node and the third node in the present application are UE201 and UE241, respectively.

As an embodiment, the second node and the third node in the present application are UE201 and UE241, respectively.

As an embodiment, the wireless link between the UE201 and the UE241 corresponds to a Sidelink (SL) in this application.

As an embodiment, the radio link from the UE201 to the NR node B is an uplink.

As an embodiment, the radio link from the NR node B to the UE201 is the downlink.

As an embodiment, the UE201 supports relay transmission.

As an embodiment, the UE241 supports relay transmission.

As an embodiment, the UE201 is a vehicle including an automobile.

As an embodiment, the UE241 is a vehicle including an automobile.

As an example, the gNB203 is a macro cellular (MarcoCellular) base station.

As an embodiment, the gNB203 is a Micro Cell (Micro Cell) base station.

As an embodiment, the gNB203 is a pico cell (PicoCell) base station.

As an example, the gNB203 is a flight platform device.

As an embodiment, the gNB203 is a satellite device.

Example 3

Embodiment 3 shows a schematic diagram of an embodiment of a radio protocol architecture for the user plane and the control plane according to the present application, as shown in fig. 3. Fig. 3 is a schematic diagram illustrating an embodiment of radio protocol architecture for the user plane 350 and the control plane 300, fig. 3 showing the radio protocol architecture for the control plane 300 for a first node (UE, satellite or aircraft in gNB or NTN) and a second node (satellite or aircraft in gNB, UE or NTN), or between two UEs, in three layers: layer 1, layer 2 and layer 3. Layer 1 (L1 layer) is the lowest layer and implements various PHY (physical layer) signal processing functions. The L1 layer will be referred to herein as PHY301. Layer 2 (L2 layer) 305 is above PHY301 and is responsible for the link between the first and second nodes and the two UEs through PHY301. The L2 layer 305 includes a MAC (Medium Access Control) sublayer 302, an RLC (Radio Link Control) sublayer 303, and a PDCP (Packet Data Convergence Protocol) sublayer 304, which terminate at the second node. The PDCP sublayer 304 provides multiplexing between different radio bearers and logical channels. The PDCP sublayer 304 also provides security by ciphering data packets and provides handoff support between second nodes to the first node. The RLC sublayer 303 provides segmentation and reassembly of upper layer packets, retransmission of lost packets, and reordering of packets to compensate for out-of-order reception due to HARQ. The MAC sublayer 302 provides multiplexing between logical and transport channels. The MAC sublayer 302 is also responsible for allocating the various radio resources (e.g., resource blocks) in one cell between the first nodes. The MAC sublayer 302 is also responsible for HARQ operations. A RRC (Radio Resource Control) sublayer 306 in layer 3 (L3 layer) in the Control plane 300 is responsible for obtaining Radio resources (i.e., radio bearers) and configuring the lower layers using RRC signaling between the second node and the first node. The PC5-S (PC 5Signaling Protocol ) sublayer 307 is responsible for processing of the Signaling Protocol of the PC5 interface. The radio protocol architecture of the user plane 350 includes layer 1 (L1 layer) and layer 2 (L2 layer), the radio protocol architecture in the user plane 350 for the first and second nodes is substantially the same for the physical layer 351, the PDCP sublayer 354 in the L2 layer 355, the RLC sublayer 353 in the L2 layer 355, and the MAC sublayer 352 in the L2 layer 355 as the corresponding layers and sublayers in the control plane 300, but the PDCP sublayer 354 also provides header compression for upper layer packets to reduce radio transmission overhead. The L2 layer 355 in the user plane 350 further includes an SDAP (Service Data Adaptation Protocol) sublayer 356, and the SDAP sublayer 356 is responsible for mapping between QoS streams and Data Radio Bearers (DRBs) to support diversity of services. Although not shown, the first node may have several upper layers above the L2 layer 355. Also included are a network layer (e.g., IP layer) that terminates at the P-GW on the network side and an application layer that terminates at the other end of the connection (e.g., far end UE, server, etc.). For UEs involving relay services, the control plane may also include an adaptation sublayer AP308, the user plane may also include an adaptation sublayer AP358, and the introduction of an adaptation layer may facilitate lower layers, such as the MAC layer, e.g., the RLC layer, to multiplex and/or differentiate data from multiple source UEs. In addition, the adaptation sublayers AP308 and AP358 may also serve as sublayers within the PDCP304 and PDCP354, respectively. The RRC306 may be used to handle RRC signaling for the Uu interface and signaling for the PC5 interface.

As an example, the wireless protocol architecture in fig. 3 is applicable to the first node in this application.

The radio protocol architecture of fig. 3 applies to the second node in this application as an example.

As an example, the radio protocol architecture in fig. 3 is applicable to the third node in the present application.

As an embodiment, the first message in the present application is generated in RRC306 or PC5-S307 or NAS.

As an embodiment, the second message in the present application is generated in RRC306, PC5-S307, or NAS.

As an embodiment, the first PDCP PDU in the present application is generated in the PDCP354.

As an embodiment, the second PDCP PDU in this application is generated in the PDCP354.

As an embodiment, the second PDCP SDU in this application is generated in a layer above the SDAP356 or the PDCP354.

As an embodiment, the first report in this application is generated in the PDCP354.

As an embodiment, the second report in this application is generated in the PDCP354.

As an embodiment, the first RLC PDU in this application is generated in the PDCP353.

Example 4

Embodiment 4 shows a schematic diagram of a first communication device and a second communication device according to the present application, as shown in fig. 4. Fig. 4 is a block diagram of a first communication device 450 and a second communication device 410 communicating with each other in an access network.

The first communications device 450 includes a controller/processor 459, a memory 460, a data source 467, a transmit processor 468, a receive processor 456, a multi-antenna transmit processor 457, a multi-antenna receive processor 458, a transmitter/receiver 454, and an antenna 452.

The second communications device 410 includes a controller/processor 475, a memory 476, a receive processor 470, a transmit processor 416, a multiple antenna receive processor 472, a multiple antenna transmit processor 471, a transmitter/receiver 418 and an antenna 420.

In the transmission from the second communication device 410 to the first communication device 450, at the second communication device 410, upper layer data packets from the core network are provided to the controller/processor 475. The controller/processor 475 implements the functionality of the L2 layer. In transmissions from the second communications device 410 to the first communications device 450, the controller/processor 475 provides header compression, encryption, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocation to the first communications device 450 based on various priority metrics. The controller/processor 475 is also responsible for retransmission of lost packets and signaling to the first communication device 450. The transmit processor 416 and the multi-antenna transmit processor 471 implement various signal processing functions for the L1 layer (i.e., the physical layer). The transmit processor 416 implements coding and interleaving to facilitate Forward Error Correction (FEC) at the second communication device 410, as well as mapping of signal constellation based on various modulation schemes (e.g., binary Phase Shift Keying (BPSK), quadrature Phase Shift Keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The multi-antenna transmit processor 471 performs digital spatial precoding, including codebook-based precoding and non-codebook based precoding, and beamforming on the coded and modulated symbols to generate one or more spatial streams. Transmit processor 416 then maps each spatial stream to subcarriers, multiplexes with reference signals (e.g., pilots) in the time and/or frequency domain, and then uses an Inverse Fast Fourier Transform (IFFT) to generate the physical channels carrying the time-domain multicarrier symbol streams. The multi-antenna transmit processor 471 then performs analog precoding/beamforming operations on the time domain multi-carrier symbol stream. Each transmitter 418 converts the baseband multicarrier symbol stream provided by the multi-antenna transmit processor 471 into a radio frequency stream that is then provided to a different antenna 420.

In a transmission from the second communications apparatus 410 to the first communications apparatus 450, each receiver 454 receives a signal through its respective antenna 452 at the first communications apparatus 450. Each receiver 454 recovers information modulated onto a radio frequency carrier and converts the radio frequency stream into a baseband multi-carrier symbol stream that is provided to a receive processor 456. Receive processor 456 and multi-antenna receive processor 458 implement the various signal processing functions of the L1 layer. A multi-antenna receive processor 458 performs receive analog precoding/beamforming operations on the baseband multi-carrier symbol streams from receiver 454. Receive processor 456 converts the baseband multicarrier symbol stream after the receive analog precoding/beamforming operation from the time domain to the frequency domain using a Fast Fourier Transform (FFT). In the frequency domain, the physical layer data signals and the reference signals to be used for channel estimation are demultiplexed by the receive processor 456, and the data signals are subjected to multi-antenna detection in the multi-antenna receive processor 458 to recover any spatial streams destined for the first communication device 450. The symbols on each spatial stream are demodulated and recovered at a receive processor 456 and soft decisions are generated. The receive processor 456 then decodes and deinterleaves the soft decisions to recover the upper layer data and control signals transmitted by the second communications device 410 on the physical channel. The upper layer data and control signals are then provided to a controller/processor 459. The controller/processor 459 implements the functions of the L2 layer. The controller/processor 459 may be associated with a memory 460 that stores program codes and data. Memory 460 may be referred to as a computer-readable medium. In transmissions from the second communications device 410 to the second communications device 450, the controller/processor 459 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the core network. The upper layer packet is then provided to all protocol layers above the L2 layer. Various control signals may also be provided to L3 for L3 processing.

In a transmission from the first communications device 450 to the second communications device 410, a data source 467 is used at the first communications device 450 to provide upper layer data packets to a controller/processor 459. Data source 467 represents all protocol layers above the L2 layer. Similar to the send function at the second communications apparatus 410 described in the transmission from the second communications apparatus 410 to the first communications apparatus 450, the controller/processor 459 performs header compression, encryption, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocation, performing L2 layer functions for the user plane and control plane. The controller/processor 459 is also responsible for retransmission of lost packets and signaling to said second communication device 410. A transmit processor 468 performs modulation mapping, channel coding, and digital multi-antenna spatial precoding by a multi-antenna transmit processor 457 including codebook-based precoding and non-codebook based precoding, and beamforming, and the transmit processor 468 then modulates the resulting spatial streams into multi-carrier/single-carrier symbol streams, which are provided to different antennas 452 via a transmitter 454 after analog precoding/beamforming in the multi-antenna transmit processor 457. Each transmitter 454 first converts the baseband symbol stream provided by the multi-antenna transmit processor 457 into a radio frequency symbol stream and provides the radio frequency symbol stream to the antenna 452.

In a transmission from the first communication device 450 to the second communication device 410, the functionality at the second communication device 410 is similar to the receiving functionality at the first communication device 450 described in the transmission from the second communication device 410 to the first communication device 450. Each receiver 418 receives an rf signal through its respective antenna 420, converts the received rf signal to a baseband signal, and provides the baseband signal to a multi-antenna receive processor 472 and a receive processor 470. The receive processor 470 and the multiple antenna receive processor 472 collectively implement the functions of the L1 layer. The controller/processor 475 implements L2 layer functions. The controller/processor 475 can be associated with a memory 476 that stores program codes and data. Memory 476 may be referred to as a computer-readable medium. In transmission from the first communications device 450 to the second communications device 410, the controller/processor 475 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover upper layer packets from the UE 450. Upper layer data packets from the controller/processor 475 may be provided to a core network.

As an embodiment, the first communication device 450 apparatus includes: at least one processor and at least one memory including computer program code; the at least one memory and the computer program code configured to, for use with the at least one processor, the first communication device 450 apparatus at least: receiving a first message; re-establishing the first PDCP entity in response to receiving the first message; transmitting a first PDCP PDU generated by the first PDCP entity; wherein the first PDCP PDU includes a first domain and data, and the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the first communication device 450 includes: a memory storing a program of computer readable instructions that when executed by at least one processor result in actions comprising: receiving a first message; re-establishing the first PDCP entity in response to receiving the first message; transmitting a first PDCP PDU generated by the first PDCP entity; wherein the first PDCP PDU includes a first domain and data, and the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the second communication device 410 apparatus includes: at least one processor and at least one memory including computer program code; the at least one memory and the computer program code are configured for use with the at least one processor. The second communication device 410 means at least: sending a first message; the first message is used to trigger re-establishing a first PDCP entity; receiving a first PDCP PDU generated by the first PDCP entity; wherein the first PDCP PDU includes a first domain and data, and the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the second communication device 410 apparatus includes: a memory storing a program of computer readable instructions that when executed by at least one processor result in actions comprising: sending a first message; the first message is used to trigger re-establishing a first PDCP entity; receiving a first PDCP PDU generated by the first PDCP entity; wherein the first PDCP PDU includes a first domain and data, and the first message is used to set the first domain of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the first communication device 450 corresponds to a first node in the present application.

As an embodiment, the second communication device 410 corresponds to a second node in the present application.

As an embodiment, the second communication device 410 corresponds to a third node in the present application.

For one embodiment, the first communication device 450 is a UE.

As an embodiment, the first communication device 450 is a vehicle-mounted terminal.

For one embodiment, the second communication device 410 is a UE.

As an embodiment, the first communication device 410 is a vehicle-mounted terminal.

For one embodiment, receiver 456 (including antenna 460), receive processor 452, and controller/processor 490 are used to receive the first message.

For one embodiment, receiver 456 (including antenna 460), receive processor 452, and controller/processor 490 are used to receive the second report in this application.

For one embodiment, a transmitter 456 (including an antenna 460), a transmit processor 455, and a controller/processor 490 are used to send the second message.

For one embodiment, a transmitter 456 (including an antenna 460), a transmit processor 455, and a controller/processor 490 are used to transmit the first PDCP PDU in the present application.

For one embodiment, a transmitter 456 (including an antenna 460), a transmit processor 455, and a controller/processor 490 are used to transmit the first RLC PDU in this application.

For one embodiment, a transmitter 456 (including an antenna 460), a transmit processor 455, and a controller/processor 490 are used to send the first report in this application.

For one embodiment, transmitter 416 (including antenna 420), transmit processor 412, and controller/processor 440 are used to transmit the first message in this application.

For one embodiment, transmitter 416 (including antenna 420), transmit processor 412, and controller/processor 440 are used to send the second report in this application.

For one embodiment, the receiver 416 (including the antenna 420), the receive processor 412, and the controller/processor 440 are configured to receive the first PDCP PDU as described herein.

For one embodiment, the receiver 416 (including the antenna 420), the receive processor 412, and the controller/processor 440 are used to receive the first RLC PDU in this application.

For one embodiment, receiver 416 (including antenna 420), receive processor 412, and controller/processor 440 are used to receive the first report in this application.

Example 5

Embodiment 5 illustrates a wireless signal transmission flow chart according to an embodiment of the present application, as shown in fig. 5. In fig. 5, U01 corresponds to a first node of the present application, and U02 corresponds to a second node of the present application, and it is specifically illustrated that the sequence in the present example does not limit the sequence of signal transmission and the sequence of implementation in the present application, and the steps in F51 are optional.

ForFirst node U01Receiving a first message in step S5101; transmitting the first PDCP PDU in step S5102; receiving a second report in step S5103; the first report is sent in step S5104.

For theSecond node U02In step S5201, a first message is transmitted; receiving a first PDCP PDU in step S5202; transmitting a second report in step S5203; the first report is received in step S5204.

In embodiment 5, in response to receiving the first message, the first node U01 reconstructs the first PDCP entity; the first PDCP PDU is generated by the first PDCP entity; the first PDCP PDU includes a first field and data, the first message being used to set the first field of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the communication interface between the first node U01 and the second node U02 is Uu.

As an embodiment, the communication interface between the first node U01 and the second node U02 is a PC5.

As an embodiment, the radio bearer associated with the first PDCP entity is a first radio bearer, and the identity of the first radio bearer is used for ciphering the data included in the first PDCP PDU.

As an embodiment, the second node N02 is a serving cell of the first node U01.

As an embodiment, the second node N02 is a primary serving cell of the first node U01.

As an embodiment, the second node N02 is a group of serving cells of the first node U01.

As an embodiment, the second node N02 is a relay node of the first node U01.

As an embodiment, before the second node N02 sends the first message, the second node N02 receives a message from a core network indicating that the key of the first node U01 needs to be updated.

As a sub-embodiment of the above embodiment, said message from the core network is used to trigger said first message.

As an embodiment, before the second node N02 sends the first message, the second node N02 receives a message from the core network to be used for indicating or generating a new key for the first node U01.

As an embodiment, before the second node N02 sends the first message, the second node N02 receives a message from a core network indicating that the security context of the first node U01 is not synchronized.

As an embodiment, before the second node N02 sends the first message, the first node U01 receives a message from the core network indicating that the key of the first node U01 needs to be updated.

As an embodiment, before the second node N02 sends the first message, the first node U01 receives a message from a core network to be used for indicating or generating a new key of the first node U01.

As a sub-embodiment of the above embodiment, the message from the core network is used to trigger the re-establishment of the first PDCP entity.

For one embodiment, the message from the core network comprises SECURITY MODE COMMAND.

For one embodiment, the message from the core network includes a PDU SESSION MODIFICATION COMMAND.

As one embodiment, said message from the core network comprises an AUTHENTICATION REQUEST.

As an embodiment, the message from the core network comprises a REGISTRATION ACCEPT.

For one embodiment, the message from the core network includes SERVICE ACCEPT.

For one embodiment, the message from the core network includes a CONFIGURATION UPDATE COMMAND.

As an embodiment, the first message is from a core network, and the second node N02 forwards the first message.

As an embodiment, the radio bearer occupied by the first PDCP PDU is suspended before the first PDCP entity is re-established.

As an embodiment, the radio bearer occupied by the first PDCP PDU is active before the first PDCP entity is re-established.

As an embodiment, the first PDCP PDU uses the first radio bearer.

As an embodiment, the first radio bearer is an AM DRB.

As one embodiment, the first radio bearer is an UM DRB.

As an embodiment, the first PDCP PDU is forwarded by a relay node before being received by the second node N02.

As an embodiment, the D/C field of the header of the first PDCP PDU is 1.

As an embodiment, the act of transmitting the first PDCP PDU includes: sending a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN; wherein the first message is not used to reset the first RLC SN;

as a sub-embodiment of this embodiment, the first RLC PDU is generated by the first node U01;

as a sub-embodiment of this embodiment, the first RLC PDU is generated by a node other than the first node U01;

as a sub-embodiment of this embodiment, the RLC SDU corresponding to the first RLC PDU is the first PDCP PDU;

as a sub-embodiment of this embodiment, the first RLC PDU includes at least a part of the first PDCP PDU;

as a sub-embodiment of this embodiment, the header of the first RLC PDU includes a first RLC SN;

as a sub-embodiment of this embodiment, the mode of the RLC used by the RLC entity corresponding to the first RLC PDU is AM;

as a sub-embodiment of this embodiment, the RLC mode used by the RLC entity corresponding to the first RLC PDU is UM;

as a sub-embodiment of this embodiment, the mode of the RLC used by the RLC entity corresponding to the first RLC PDU is bidirectional UM;

as a sub-embodiment of this embodiment, the RLC layer where the RLC entity corresponding to the first RLC PDU is located is a lower layer of the first PDCP entity;

as a sub-embodiment of this embodiment, the RLC bearer corresponding to the first RLC PDU belongs to a bearer of a PC5 interface;

as a sub-embodiment of this embodiment, the RLC bearer corresponding to the first RLC PDU belongs to a bearer of a Uu interface;

as a sub-embodiment of this embodiment, the first message is used to reset the first RLC SN;

as a sub-embodiment of this embodiment, the first message is used to reconstruct the RLC entity corresponding to the first RLC PDU.

As an embodiment, the first report indicates that the second PDCP SDU was not received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity;

as a sub-embodiment of this embodiment, the first report is a PDCP status report;

as a sub-embodiment of this embodiment, said first report indicates said second sequence number by a bitmap;

as a sub-embodiment of this embodiment, the PDCP SN with which the second PDCP SDU is associated is the second sequence number before the first PDCP entity is re-established;

as a sub-embodiment of this embodiment, the re-establishment of the first PDCP entity does not affect PDCP SDUs to which PDCP SNs have been assigned or associated;

as a sub-embodiment of this embodiment, the second sequence number is a PDCP SN;

as a sub-embodiment of this embodiment, the second sequence number is a COUNT value of a PDCP SDU;

as a sub-embodiment of this embodiment, the first report indicates the second sequence number through an FMC field;

as a sub-embodiment of this embodiment, the PDCP SDUs corresponding to all sequence numbers indicated by the first report are not received by the sender of the first report;

as a sub-embodiment of this embodiment, the PDU Type field of the first report is set to 000;

as a sub-embodiment of this embodiment, the first report does not carry PDCP SNs;

as a sub-embodiment of this embodiment, the first report is a control type PDCP PDU;

as a sub-embodiment of this embodiment, the COUNT value associated with the second PDCP SDU before the first PDCP entity is re-established is updated after the first PDCP entity is re-established; the associated PDCP SN of the second PDCP SDU before the first PDCP entity is reconstructed is not updated after the first PDCP entity is reconstructed.

As an embodiment, the first report indicates that the second PDCP SDU was not received by indicating a fourth sequence number; the PDCP sequence number assigned to the second PDCP SDU before the first PDCP entity is re-established is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity;

as a sub-embodiment of this embodiment, the first report indicates the fourth sequence number by a bitmap;

as a sub-embodiment of this embodiment, the fourth sequence number is a PDCP SN;

as a sub-embodiment of this embodiment, the fourth sequence number is a COUNT value of a PDCP SDU;

as a sub-embodiment of this embodiment, the first report indicates the fourth sequence number through an FMC field;

as a sub-embodiment of this embodiment, the associated PDCP SN of the second PDCP SDU before the first PDCP entity is re-established is updated after the first PDCP entity is re-established;

as a sub-embodiment of this embodiment, the COUNT value associated with the second PDCP SDU before the first PDCP entity is re-established is updated after the first PDCP entity is re-established;

as a sub-embodiment of this embodiment, the associated PDCP SN of the second PDCP SDU before the first PDCP entity is re-established is updated after the first PDCP entity is re-established; the COUNT value associated with the second PDCP SDU before the first PDCP entity is re-established is not updated after the first PDCP entity is re-established;

as a sub-embodiment of this embodiment, the COUNT value associated with the second PDCP SDU before the first PDCP entity is re-established is updated after the first PDCP entity is re-established; the associated PDCP SN of the second PDCP SDU before the first PDCP entity is reestablished is updated after the first report transmission.

As an embodiment, the reception of the first message is used to trigger the sending of the first report.

As an embodiment, the re-establishment of the first PDCP entity triggers the sending of the first report.

The second report is used to indicate the first COUNT value as an embodiment; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being other than 0;

as a sub-embodiment of this embodiment, the second report is a PDCP status report;

as a sub-embodiment of this embodiment, the FMC (First Missing Count) field of the second report indicates a First Missing Count value;

as a sub-embodiment of this embodiment, the FMC (First Missing Count) field of the second report indicates a Count value associated with the First Missing PDCP SDU;

as a sub-embodiment of this embodiment, the at least one state variable of the first PDCP entity comprises TX _ NEXT;

as a sub-embodiment of this embodiment, the at least one state variable of the first PDCP entity comprises RX _ NEXT;

as a sub-embodiment of this embodiment, the at least one state variable of the first PDCP entity comprises RX _ DELIV;

as a sub-embodiment of this embodiment, the first initial value is greater than 0;

as a sub-embodiment of this embodiment, the value of the first initial value ranges from 0 to 2 raised to the power of Q minus 1; wherein Q is a length of a PDCP sequence number allocated by the first PDCP entity;

as a sub-embodiment of this embodiment, the first initial value ranges from 0 to 2 raised to the power Q minus 1; wherein Q is the length of the sequence number of the first PDCP PDP;

as a sub-embodiment of this embodiment, the first PDCP entity updates the COUNT associated with the PDCP SDU which is not correctly received and indicated by the second report;

as a sub-embodiment of this embodiment, the first PDCP entity respectively increments the first initial value for the COUNT associated with the PDCP SDU indicated by the second report which has not been correctly received;

as a sub-embodiment of this embodiment, the PDCP SNs associated with the first PDCP entity for the incorrectly received PDCP SDUs indicated by the second report are respectively incremented by the first initial value;

as a sub-embodiment of this embodiment, the COUNT value associated with the first PDCP entity for the PDCP SDUs indicated by the second report that were not correctly received is discarded;

as a sub-embodiment of this embodiment, the COUNT associated by the first PDCP entity for PDCP SDUs not correctly received indicated by the second report is determined and associated again according to TX _ NEXT;

as a sub-embodiment of this embodiment, the first PDCP entity ciphers for PDCP SDUs indicated by the second report that were not correctly received using the newly associated COUNT value;

as a sub-embodiment of this embodiment, the first PDCP entity retransmits for PDCP SDUs that were not correctly received as indicated by the second report, the first field of the retransmitted transmitted PDCP PDU indicating that the retransmitted PDCP PDU was generated after re-establishment of the first PDCP entity;

as a sub-embodiment of this embodiment, the reception of the second report is used to trigger a re-establishment of the first PDCP entity;

as a sub-embodiment of this embodiment, a field of the second report indicates that the first PDCP entity is re-established.

For one embodiment, the first PDCP PDU is transmitted over a secondary link.

As an embodiment, a MAC subheader of the MAC sub-PDU carrying the first PDCP PDU includes at least a portion of bits of the first link layer identity and at least a portion of bits of the second link layer identity.

As a sub-embodiment of the above embodiment, the first link layer identity is used to identify the first node U01.

As a sub-embodiment of the above embodiment, the second link layer identity is used to identify a relay node of the first node U01.

As a sub-embodiment of the above embodiment, said second link layer identity is used to identify said second node N02.

Example 6

Embodiment 6 illustrates a wireless signal transmission flow chart according to an embodiment of the present application, as shown in fig. 6. In fig. 6, U11 corresponds to the first node of the present application, and U13 corresponds to the third node of the present application, and it is specifically illustrated that the sequence in the present example does not limit the sequence of signal transmission and the sequence of implementation in the present application, and the step in F61 is optional. Example 6 is based on example 5, and the parts involved in example 6 but not described in detail can be referred to in example 5.

ForFirst node U11In step S6101, a second message is sent; a third message is received in step S6102.

For theThird node U13Receiving a second message in step S6301; a third message is transmitted in step S6302.

As an embodiment, the third node U13 is a relay node of the first node U11.

As an embodiment, the third node U13 is a relay node of the first node U11 to a serving cell.

As an embodiment, the interface between the first node U01 and the third node U13 is a PC5 interface.

For one embodiment, the second message includes higher layer signaling.

As an embodiment, the second message includes RRC (Radio Resource Control) signaling.

As one embodiment, the RRC signaling includes PC5-RRC signaling.

As an embodiment, the second message comprises PC5-S signaling.

As one embodiment, the second message includes ProSe signaling.

As an embodiment, the second message is sent on a Uu interface.

As an embodiment, the second message is sent over the PC5 interface.

As an embodiment, the second message is transmitted through an SCCH (Sidelink Control Channel) Channel.

As an embodiment, the second message is transmitted through an STCH (Sidelink Traffic Channel) Channel.

As an embodiment, the second message is transmitted over a PSCCH (Physical sidelink control channel) channel.

As an embodiment, the second message is transmitted through a psch (Physical sidelink shared channel) channel.

As an embodiment, the second message is transmitted through a PSBCH (Physical sidelink broadcast channel) channel.

As an embodiment, the second message is transmitted over a SL-SCH channel.

As an embodiment, the second message is transmitted over a sidelink.

As one embodiment, the second message is used to configure a DRB (Data RB).

As an embodiment, the second message is used to configure an RB (Radio Bearer).

As an embodiment, the second message is used to configure a SLRB (Sidelink RB).

For one embodiment, the second message includes rrcreconconfiguresildenk.

As an embodiment, the second message comprises rrcreeconfiguration completesidelink.

As an embodiment, the second message includes a partial field (field) in rrcreeconfigurationsidelink.

As an embodiment, the second message comprises rrcreeconfiguration.

For one embodiment, the second message includes SIB12.

As one embodiment, the second message includes SLRB-Config.

For one embodiment, the second message comprises sl-PDCP-ConfigPC5.

For one embodiment, the second message comprises sl-RLC-ConfigPC5.

For one embodiment, the second message comprises sl-MAC-LogicalChannelConfigPC5.

As an embodiment, the second message comprises PC5-S signaling.

As an embodiment, the second message comprises SL-LogicalChannelConfigPC5.

As an embodiment, the second message comprises SL-LogicalChannelConfig.

For one embodiment, the second message comprises SL-LogicalChannelConfig-r16.

For one embodiment, the second message comprises SL-LogicalChannelConfig-r17.

As an embodiment, the second message comprises a partial field in the SL-LogicalChannelConfig.

For one embodiment, the second message comprises an sl-RLC-Config.

For one embodiment, the second message comprises sl-RLC-Config-r16.

For one embodiment, the second message comprises sl-RLC-Config-r17.

For one embodiment, the second message comprises a portion of a field in the sl-RLC-Config.

For one embodiment, the second message comprises an sl-LogicalChannelGroup.

As an embodiment, the second message comprises rrcconnectionreconfiguration sildenink.

For one embodiment, the second message includes RRCConnectionReconfiguration.

For one embodiment, the second message comprises a DIRECT LINK ESTABLISHMENT REQUEST.

For one embodiment, the second message comprises a DIRECT LINK update ACCEPT.

As an embodiment, the second message comprises a DIRECT LINK MODIFICATION REQUEST.

For one embodiment, the second message comprises a DIRECT LINK MODIFICATION ACCEPT.

For one embodiment, the second message comprises a DIRECT LINK KEEPALIVE REQUEST.

For one embodiment, the second message comprises a DIRECT LINK KEEPALIVE RESPONSE.

As one embodiment, the second message includes a discover REQUEST.

As an embodiment, the second message comprises a discover _ RESPONSE.

For one embodiment, the second message includes a Direct Security Mode Command.

For one embodiment, the second message includes a Direct Security Mode Complete.

As an embodiment, the second message is a message from a serving cell forwarded by the first node U11.

As an embodiment, the act of re-establishing the first PDCP entity comprises: re-establishing a first RLC entity, the first RLC entity associated with the first PDCP entity; the second message indicates that the first RLC entity is re-established;

as a sub-embodiment of this embodiment, the first RLC entity is in the third node U13;

as a sub-embodiment of this embodiment, the first RLC entity being re-established comprises: discarding all RLC SDUs, RLC SDU segments and RLC PDUs;

as a sub-embodiment of this embodiment, the first RLC entity being re-established comprises: stopping and resetting the timers of all RLC entities;

as a sub-embodiment of this embodiment, the first RLC entity being re-established comprises: all state variables are reset and set to initial values.

In one embodiment, the first RLC entity is configured to transmit the first PDCP PDU.

As an embodiment, the first RLC entity generates a first RLC PDU, and the first RLC PDU carries the first PDCP PDU.

As an embodiment, the third message is used for feeding back the second message.

As an embodiment, the second message is used for feeding back the third message.

For one embodiment, the third message includes higher layer signaling.

As an embodiment, the third message includes RRC (Radio Resource Control) signaling.

As one embodiment, the RRC signaling includes PC5-RRC signaling.

For one embodiment, the third message includes PC5-S signaling.

As an embodiment, the third message comprises ProSe signaling.

As an embodiment, the third message is sent on a Uu interface.

As an embodiment, the third message is sent over the PC5 interface.

As an embodiment, the third message is transmitted through a SCCH (Sidelink Control Channel) Channel.

As an embodiment, the third message is transmitted through an STCH (Sidelink Traffic Channel) Channel.

As an example, the third message is transmitted over a PSCCH (Physical sidelink control channel) channel.

As an embodiment, the third message is transmitted through a psch (Physical sidelink shared channel) channel.

As an embodiment, the third message is transmitted through a PSBCH (Physical sidelink broadcast channel) channel.

As an example, the third message is transmitted over a SL-SCH channel.

As an embodiment, the third message is transmitted over a sidelink.

As one embodiment, the third message is used to configure a DRB (Data RB).

As an embodiment, the third message is used to configure an RB (Radio Bearer).

As an embodiment, the third message is used to configure an SLRB (Sidelink RB).

As an embodiment, the third message comprises RRCReconfigurationSidelink.

As an embodiment, the third message comprises rrcreconconfigurationcompletessildelink.

As an example, the third message includes a partial field (field) in RRCReconfigurationSidelink.

As an embodiment, the third message comprises rrcreconconfiguration.

As an embodiment, the third message includes SIB12.

For one embodiment, the third message comprises an SLRB-Config.

For one embodiment, the third message comprises sl-PDCP-ConfigPC5.

For one embodiment, the third message comprises sl-RLC-ConfigPC5.

For one embodiment, the third message comprises sl-MAC-LogicalChannelConfigPC5.

For one embodiment, the third message includes PC5-S signaling.

As an embodiment, the third message comprises SL-LogicalChannelConfigPC5.

As an embodiment, the third message comprises SL-LogicalChannelConfig.

As an example, the third message comprises SL-LogicalChannelConfig-r16.

As an example, the third message comprises SL-LogicalChannelConfig-r17.

As an embodiment, the third message comprises a part of the field in the SL-logical channelconfig.

For one embodiment, the third message comprises sl-RLC-Config.

For one embodiment, the third message comprises sl-RLC-Config-r16.

For one embodiment, the third message comprises sl-RLC-Config-r17.

For one embodiment, the third message comprises a portion of a field in the sl-RLC-Config.

For one embodiment, the third message comprises an sl-logical channelgroup.

As an embodiment, the third message comprises rrcconnectionreconfiguration sildenink.

As an embodiment, the third message comprises an RRCConnectionReconfiguration.

As one embodiment, the third message comprises a DIRECT LINK update REQUEST.

For one embodiment, the third message comprises a DIRECT LINK ESTABLISHMENT ACCEPT.

As an embodiment, the third message comprises a DIRECT LINK MODIFICATION REQUEST.

For one embodiment, the third message comprises a DIRECT LINK MODIFICATION ACCEPT.

For one embodiment, the third message comprises a DIRECT LINK KEEPALIVE REQUEST.

As an embodiment, the third message comprises a DIRECT LINK KEEPALIVE RESPONSE.

As an example, the third message comprises a discover REQUEST.

As an embodiment, the third message comprises a discover _ RESPONSE.

As one embodiment, the third message includes a Direct Security Mode Command.

As an example, the third message includes a Direct Security Mode Complete.

As an embodiment, the reception of the third message is used to trigger a re-establishment of the first PDCP entity.

As an embodiment, the re-establishment of the first PDCP entity triggers the sending of the second message.

As an embodiment, the second message is used to indicate to release the RLC entity associated with the first PDCP entity.

In one embodiment, the second message is used to indicate establishment of a new RLC entity associated with the first PDCP entity.

As an embodiment, the second message indicates a target logical channel identity, and a MAC subheader of a MAC sub-PDU carrying the first PDCP PDU includes the first logical channel identity; the first logical channel identity is different from the target logical channel identity.

As an embodiment, the second message indicates a target logical channel identity, and the MAC subheader carrying the MAC sub-PDU of the first PDCP PDU includes the first logical channel identity; the first logical channel identity is the same as the target logical channel identity.

As one embodiment, the second message includes an identity of the first radio bearer.

For one embodiment, the second message includes the first link layer identity.

For one embodiment, the third message includes an identity of the first radio bearer.

Example 7

Embodiment 7 illustrates a schematic diagram of PDCP PDUs according to an embodiment of the present application, as shown in fig. 7.

As an embodiment, one PDCP PDU includes a header and Data, wherein the Data (Data) is a field of one PDCP PDU for carrying the Data (Data).

For one embodiment, a header of one PDCP PDU includes a first field.

As an embodiment, before the first field included in the header of one PDCP PDU, optionally, other bits exist;

as a sub-embodiment of the above embodiment, the other bits correspond to other fields.

As an embodiment, after the first field included in the header of one PDCP PDU, optionally, other bits exist.

For one embodiment, the first field includes 12 bits.

For one embodiment, the first field includes 18 bits.

For one embodiment, the length of the first domain is configurable.

As an embodiment, the bits preceding the first field are higher order bits.

As an embodiment, the bits after the first field are lower order bits.

As an example, the PDCP PDU in fig. 7 is applied to the DRB.

As an embodiment, the header of the PDCP PDU of FIG. 7 further includes a D/C field, wherein the D/C field occupies 1 bit.

As an embodiment, the PDCP PDU in fig. 7 is a PDU generated by the first PDCP entity.

For one embodiment, the first domain is a PDCP SN domain.

As an embodiment, the first field has a length of K bits, and the first message is used to indicate that the first field of the first PDCP PDU is set to K least significant bits of a first initial value.

As a sub-embodiment of the above embodiment, the first PDCP PDU is a first PDCP PDU generated after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the first PDCP PDU is a first data PDCP PDU generated after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, K is a positive integer.

As a sub-embodiment of the above embodiment, K is one of {1,2,3,4,12, 18 }.

As a sub-embodiment of the above embodiment, the first message indicates that a first state variable, the value of which is used to set the first field, is reset and its initial value is set to the first initial value.

As a sub-embodiment of the above embodiment, the first message indicates that a first state variable, the value of which is set to the first field, is reset and its initial value is set to the first initial value.

As a sub-embodiment of the above embodiment, the first message indicates that a first state variable is reset and its initial value is set to the first initial value, the K least significant bits of the first state variable being set to the first field.

As a sub-embodiment of the above embodiment, the values of the first fields of all data PDCP PDUs transmitted after the first PDCP entity is re-established are the same.

As a sub-embodiment of the above embodiment, the values of the first fields of all data PDCP PDUs transmitted after the first PDCP entity is re-established are sequentially incremented until the maximum value identifiable by the first field restarts from 0.

As a sub-embodiment of the above embodiment, the values of the first domain of all data PDCP PDUs transmitted after the first PDCP entity is re-established are sequentially incremented until the maximum value that can be represented by the first domain starts from the first initial value again.

As a sub-embodiment of the above embodiment, the first initial value is not 0.

As a sub-embodiment of the above embodiment, the value of the first state variable is set to the first initial value.

As a sub-embodiment of the above embodiment, a sum of a value of the first state variable and an offset is set as the first initial value.

As a sub-embodiment of the above embodiment, the first field of the first PDCP PDU is equal to a remainder of the number of times the first PDCP entity is reconstructed modulo Q, Q being a power of Q1 of 2, Q1 being the number of R included in the first field.

As an embodiment, a header of the first PDCP PDU includes the first field, and the first field includes 1 or 2 or 3 bits.

As a sub-embodiment of the above embodiment, the first field of the first PDCP PDU is equal to a remainder of the number of times the first PDCP entity is reconstructed modulo Q, Q being Q1 to the power of 2, Q1 being the number of bits included in the first field.

As an embodiment, one PDCP PDU corresponds to one PDCP SDU.

As an embodiment, the format of the PDCP PDU in fig. 7 is applicable to the first PDCP PDU of the present application.

As an embodiment, the format of the PDCP PDU in fig. 7 is applicable to the second PDCP PDU of the present application.

As an example, the format of the PDCP PDU in fig. 7 is applicable to the third PDCP PDU of the present application.

As an example, the PDCP PDU and the first field in fig. 7 are applied to the first PDCP PDU of the present application.

For one embodiment, the first field of the PDCP PDU of fig. 7 occupies 1 bit, and the header of the PDCP PDU includes 2R bits, wherein the header of the PDCP PDU of fig. 7 includes a 12-bit SN field.

As an example, the first field of the PDCP PDU of FIG. 7 occupies 2 bits, and the header of the PDCP PDU includes 1R bit, wherein the header of the PDCP PDU of FIG. 7 includes a 12-bit SN field.

As an example, the first field of the PDCP PDU in FIG. 7 occupies 3 bits, and the header of the PDCP PDU includes 0R bits, wherein the header of the PDCP PDU in FIG. 7 includes a 12-bit SN field.

For one embodiment, the first field of the PDCP PDU of FIG. 7 occupies 1 bit, and the header of the PDCP PDU includes 4R bits, wherein the header of the PDCP PDU of FIG. 7 includes an 18-bit SN field.

For one embodiment, the first field of the PDCP PDU of FIG. 7 occupies 2 bits, and the header of the PDCP PDU includes 3R bits, wherein the header of the PDCP PDU of FIG. 7 includes an 18-bit SN field.

For one embodiment, the first field of the PDCP PDU of FIG. 7 occupies 3 bits, and the header of the PDCP PDU includes 2R bits, wherein the header of the PDCP PDU of FIG. 7 includes an 18-bit SN field.

For one embodiment, the first field of the PDCP PDU of FIG. 7 occupies 4 bits, and the header of the PDCP PDU includes 1R bit, wherein the header of the PDCP PDU of FIG. 7 includes an 18-bit SN field.

For one embodiment, the first field of the PDCP PDU of FIG. 7 occupies 5 bits, and the header of the PDCP PDU includes 0R bits, wherein the header of the PDCP PDU of FIG. 7 includes an 18-bit SN field.

As an embodiment, the first field of the first PDCP PDU indicates a number of times the first PDCP entity is re-established.

As an embodiment, the first field of the first PDCP PDU is equal to a remainder of the number of times the first PDCP entity is reconstructed modulo Q, Q being a power of Q1 of 2, Q1 being a number of bits included in the first field.

As an embodiment, the first field is a partial bit in PDCP Data; as a sub-embodiment of this embodiment, the first field is the first B bytes in the Data of a PDCP PDU, where B is a positive integer, e.g., B equals 1.

As an embodiment, the first field is a field carrying check bits in PDCP PDUs.

As a sub-embodiment of this embodiment, the check bit is used to check whether the first PDCP PDU is generated after the PDCP entity is re-established.

As a sub-embodiment of this embodiment, the check bit is used to check whether the first PDCP PDU is generated after the PDCP entity is reconstructed X times, where X is a positive integer.

Example 8

Embodiment 8 illustrates a schematic diagram of a protocol stack for layer 2 relaying according to an embodiment of the present application, as shown in fig. 8. Embodiment 8 is based on embodiment 3 and shows a control plane protocol stack and interfaces related to a relay node.

In embodiment 8, the NAS is a non-access stratum, the Uu-RRC is an RRC protocol of a Uu interface, and the Uu-PDCP is a PDCP entity of the Uu interface; uu-RLC is the RLC entity of the Uu interface, uu-MAC is the MAC entity of the Uu interface, and Uu-PHY is the physical layer entity of the Uu interface; PC5-RLC is the RLC entity of PC5 interface; PC5-MAC is the MAC entity of PC5 interface; PC5-PHY is the physical layer entity of PC5 interface; the Adaptation is an Adaptation entity between the relay node and the network; the N2 Stack is a protocol Stack of an N2 interface, and the N2 interface is an interface between the gNB and the core network.

As an embodiment, in fig. 8, a UE corresponds to the first node of the present application, a relay corresponds to the third node of the present application, and a gNB corresponds to the second node of the present application;

as a sub-embodiment of this embodiment, the first radio bearer is a radio bearer between the UE and the gNB; the first radio bearer corresponds to the first PDCP entity;

as a sub-embodiment of this embodiment, the first RLC bearer is an RLC bearer of a Uu interface, and the first RLC bearer is an RLC bearer between the relay and the gNB; the first RLC bearer corresponds to the first RLC entity;

as a sub-embodiment of this embodiment, the SRB used for transmitting the first message is an SRB between the UE and the gNB;

as a sub-embodiment of this embodiment, the generator of the first message is the gNB;

as a sub-embodiment of this embodiment, the generator of the first message is a core network to which the gNB is connected;

as a sub-embodiment of this embodiment, the generator of the first message is the relay;

as a sub-embodiment of this embodiment, the second message is sent using the SRBs other than the SRB used for transmitting the first signaling;

as a sub-embodiment of this embodiment, the recipient of the second message and the generator of the first message are not the same;

as a sub-embodiment of this embodiment, the recipient of the second message is a node capable of decoding the second message.

As an example, the second message is transmitted through the PC5 interface in fig. 8.

In an embodiment, the second message is generated in a NAS layer or a PC5-RRC layer of the UE.

For one embodiment, the first message is a NAS message.

As an embodiment, the first message is a Uu-RRC message.

As an embodiment, the first PDCP entity is the Uu-PDCP entity of FIG. 8.

As an example, the first RLC PDU is generated in the PC5-RLC of the UE in fig. 8.

As an embodiment, the second message is used to re-establish the relayed PC5-RLC entity.

As an embodiment, the second message is used to reset the SN of the relayed PC5-RLC entity.

As an embodiment, the first message is not used to reset a sequence number of a PC5-RLC entity of the UE.

As an embodiment, the first message is used to reset a sequence number of a PC5-RLC entity of the UE.

As an embodiment, the relayed Uu-RLC entity associated with the first PDCP entity is not re-established.

As an embodiment, the re-establishment of the first PDCP entity does not trigger a re-establishment of a Uu-RLC entity of the relay associated with the first PDCP entity.

As an embodiment, the re-establishment of the first PDCP entity is not accompanied by a re-establishment of a Uu-RLC entity associated with the first PDCP entity of the relay.

Example 9

Embodiment 9 illustrates a schematic diagram in which a first message is used to set a first field of a first PDCP PDU according to an embodiment of the present application, as shown in fig. 9.

As an embodiment, the first message indicates a first initial value, and the initial value of the state variable TX _ NEXT after the first PDCP entity is reconstructed is set to the first initial value.

As an embodiment, a value of the state variable TX _ NEXT is set to a value of the first field of the first PDCP PDU.

As an embodiment, the first message indicates the reconstruction of the first PDCP entity, the state variable TX _ NEXT of the first PDCP entity after reconstruction is set to a first initial value, which is FMC +2^ L + x where ^ is power operation, L is length-1 of the first domain, and FMC indicates the first missing COUNT value.

As a sub-embodiment of the above embodiment, FMC is indicated by said second report.

As a sub-embodiment of the above embodiment, FMC is indicated by a PDCP status report received by said first PDCP entity.

As a sub-embodiment of the above embodiment, the parameter X is a positive integer.

As a sub-embodiment of the above embodiment, the parameter X is equal to 1.

As a sub-embodiment of the above embodiment, the parameter X is equal to-1.

As a sub-embodiment of the above embodiment, the parameter X is equal to 0.

As an embodiment, the first message is for indicating a receive window of a receiver of the first PDCP PDU.

As an embodiment, the first message is for indicating a start value of a receive window of a receiver of the first PDCP PDU.

As an embodiment, a length of a receiving window of a receiver of the first PDCP PDU is fixed.

As an embodiment, the length of the receive window of the receiver of the first PDCP PDU is equal to 2^ (E-1), where ^ is a power operation and E is the length of the PDCP sequence number.

As a sub-embodiment of the above embodiment, the PDCP sequence number is 12 bits or 18 bits in length.

For one embodiment, the first initial value is not within a receive window before a receiver of the first PDCP PDU sends the first message.

As an embodiment, the first initial value is not within a receive window before a receiver of the first PDCP PDU receives a feedback message of the first message.

As an embodiment, the value of the first field determined by the first initial value is not in a receiving window of the first PDCP PDU receiver when the first message is transmitted.

In one embodiment, a value of the first field is not within a receiving window maintained by a receiver of the first PDCP PDU when the first message is transmitted, indicating that the first PDCP PDU is generated after the first PDCP entity is re-established.

As an embodiment, a difference between a value of the first field of the first PDCP PDU and a value of the first field of the last PDCP PDU sent by the first PDCP entity before re-establishment is Y.

As a sub-embodiment of the above embodiment, the first PDCP PDU is the first PDCP PDU transmitted after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the first PDCP PDU is the first data PDCP PDU transmitted after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the last PDCP PDU sent by the first PDCP entity before re-establishment is a data PDCP PDU.

As a sub-embodiment of the above embodiment, the value of Y is a positive integer.

As a sub-embodiment of the above embodiment, the value of Y is greater than the size of the PDCP receive window.

As a sub-embodiment of the above embodiment, the value of Y is equal to the size of the PDCP receiving window.

As a sub-embodiment of the above embodiment, the size of the PDCP receive window is equal to 2^ (E-1), where ^ is power operation and E is the length of the PDCP sequence number.

As a sub-embodiment of the above embodiment, the value of Y is greater than the size of a PDCP receiving window to indicate that the first PDCP PDU is generated after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the value of Y is equal to the size of a PDCP receive window for indicating that the first PDCP PDU is generated after the first PDCP entity is re-established.

As an embodiment, an initial value of a state variable TX _ NEXT of the first PDCP entity after the first PDCP entity is reset is related to a value of TX _ NEXT before the first PDCP entity is reconstructed.

As an embodiment, the first message is used to instruct the first PDCP entity re-establishment, which includes resetting a state variable of the first PDCP entity and setting the state variable of the first PDCP entity to an initial value; an initial value of a state variable TX _ NEXT of the first PDCP entity is equal to MOD (T + Z,2^ L); wherein MOD is a modulus operation, T is a TX _ NEXT value of the first PDCP entity before being reconstructed, L is a length of a sequence number of the first PDCP PDU, and ^ is a power operation.

As a sub-embodiment of the above embodiment, Z is an integer.

As a sub-embodiment of the above embodiment, Z is equal to 2^ (L-1).

As a sub-embodiment of the above embodiment, L takes the value 12 or 18.

As a sub-embodiment of the above embodiment, Z is equal to 2^ (L-1) -1.

As a sub-embodiment of the above embodiment, Z is equal to 2^ (L-1) +1.

As an embodiment, the receiving window of the PDCP entity is determined by the receiving end according to predefined parameters and parameters configured by the serving cell when the PDCP entity is established.

Example 10

Embodiment 10 illustrates a schematic diagram where a first message is not used to reset the first RLC SN according to an embodiment of the present application, as shown in fig. 10.

As an embodiment, the first message is not used to reconstruct the RLC entity corresponding to the first RLC SN.

As an embodiment, the first RLC SN is equal to SN +1 of the latest RLC PDU before the RLC PDU corresponding to the first RLC SN is transmitted.

As an embodiment, the first RLC SN and the SN of the latest RLC PDU before the RLC PDU corresponding to the first RLC SN is transmitted are kept continuous.

As an embodiment, the state variable of the RLC entity of the PC5 interface associated with the first PDCP entity is kept continuous before and after the first PDCP entity is re-established.

As a sub-embodiment of the above embodiment, the RLC entity of the PC5 interface associated with the first PDCP entity is configured to send PDCP PDUs generated by the first PDCP entity.

As an embodiment, a state variable of an RLC entity of a Uu interface associated with the first PDCP entity is continuously maintained before and after the first PDCP entity is re-established.

As an embodiment, SNs of RLC PDUs issued by an RLC entity of a PC5 interface associated with the first PDCP entity remain continuous before and after the first PDCP entity is re-established.

As an embodiment, SNs of RLC PDUs issued by an RLC entity of the Uu interface associated with the first PDCP entity remain continuous before and after the first PDCP entity is re-established.

Example 11

Embodiment 11 illustrates a schematic diagram where the second sequence number is used to determine the fourth sequence number according to an embodiment of the present invention, as shown in fig. 11.

As an embodiment, the first message is used to indicate the first initial value.

As an embodiment, a value of the fourth sequence number is equal to a sum of the second sequence number and the first initial value.

As an embodiment, a value of the fourth sequence number is equal to a sum of values of K least significant bits of the second sequence number and the first initial value.

As an embodiment, the first report indicates that the second PDCP SDU was not received by indicating a fourth sequence number; the PDCP sequence number assigned to the second PDCP SDU before the first PDCP entity is re-established is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

As an embodiment, all PDCP SDUs that have been allocated PDCP sequence numbers before the first PDCP entity is re-established but corresponding PDCP PDUs have not been submitted to lower layer transmission, the second PDCP SDU is the one in which the allocated PDCP SNs are arranged in the order of mth, and the value of the fourth sequence number is M + the second sequence number + the first initial value.

Example 12

Embodiment 12 illustrates a schematic diagram in which a first COUNT value is used to determine a first initial value according to an embodiment of the present invention, as shown in fig. 12.

As an embodiment, the second report is used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being other than 0.

As an embodiment, the first COUNT value is determined as the first initial value.

As an embodiment, the sum of the first COUNT value and a first offset is determined as the first initial value; wherein the first offset is an integer.

As an embodiment, the sum of the first COUNT value and 1 is determined as the first initial value.

As an embodiment, the sum of the first COUNT value and-1 is determined as the first initial value.

As one embodiment, the FMC field of the second report indicates the first COUNT value.

As one embodiment, the K1 least significant bits of the FMC field of the second report are determined to be the first initial value.

As an embodiment, the sum of the value of the K1 least significant bits of the FMC field of the second report and a first offset is determined as the first initial value; wherein the first offset is an integer.

As an embodiment, a sum of a value of K1 least significant bits of the FMC field of the second report and 1 is determined as the first initial value.

As an embodiment, the sum of K1 least significant bits of the FMC field of the second report and-1 is determined as the first initial value.

As an example, K1 is a positive integer.

As an example, K1 is fixed.

For one embodiment, the K1 is configurable.

As an example, K1 is equal to 12 or 18.

As an example, K1 is equal to one of {1,2,3,5 }.

For one embodiment, the K1 is equal to a length of a SN of the first PDCP PDU.

As an embodiment, the K1 is equal to a length of the first field of the first PDCP PDU.

For one embodiment, the first offset is equal to a length of a receive window of the PDCP entity.

Example 13

Embodiment 13 illustrates a block diagram of a processing apparatus for use in a first node according to an embodiment of the present application; as shown in fig. 13. In fig. 13, a processing arrangement 1300 in a first node comprises a first receiver 1301 and a first transmitter 1302. In the case of the embodiment 13, the following examples are given,

a first receiver 1301, which receives a first message; re-establishing the first PDCP entity in response to receiving the first message;

a first transmitter 1302, configured to transmit a first PDCP PDU, the first PDCP PDU being generated by the first PDCP entity;

wherein the first PDCP PDU includes a first field and data, the first message being used to set the first field of the first PDCP PDU; the first field of the first PDCP PDU is used to indicate that the first PDCP PDU was generated after a re-establishment of the first PDCP entity.

As an embodiment, the act of transmitting the first PDCP PDU comprises: sending a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN;

wherein the first message is not used to reset the first RLC SN.

As an embodiment, the first transmitter 1302, transmits the second message;

For an embodiment, the first transmitter 1302 transmits a first report indicating that the second PDCP SDU has not been received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

For an embodiment, the first transmitter 1302 transmits a first report indicating that the second PDCP SDU has not been received by indicating a fourth sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

As an example, the first receiver 1301, receives a second report, which is used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being non-0.

As an embodiment, the first message is used to indicate a first key used by the first PDCP entity to cipher the data included in the first PDCP PDU.

As an embodiment, the first node is a User Equipment (UE).

As an embodiment, the first node is a terminal supporting a large delay difference.

As an embodiment, the first node is a terminal supporting NTN.

As an embodiment, the first node is an aircraft.

As an embodiment, the first node is a vehicle-mounted terminal.

As an embodiment, the first node is a relay.

As an embodiment, the first node is a ship.

As an embodiment, the first node is an internet of things terminal.

As an embodiment, the first node is a terminal of an industrial internet of things.

As an embodiment, the first node is a device supporting low-latency high-reliability transmission.

For one embodiment, the first receiver 1301 includes at least one of the antenna 452, the receiver 454, the receive processor 456, the multiple antenna receive processor 458, the controller/processor 459, the memory 460, or the data source 467 of embodiment 4.

For one embodiment, the first transmitter 1302 includes at least one of the antenna 452, the transmitter 454, the transmit processor 468, the multi-antenna transmit processor 457, the controller/processor 459, the memory 460, or the data source 467 of embodiment 4.

Example 14

Embodiment 14 illustrates a block diagram of a processing apparatus for use in a second node according to an embodiment of the present application; as shown in fig. 14. In fig. 14, the processing means 1400 in the second node comprises a second receiver 1402 and a second transmitter 1401. In the case of the embodiment 14, the following,

a second transmitter 1401 for transmitting the first message; the first message is used to trigger re-establishing a first PDCP entity;

a second receiver 1402 for receiving a first PDCP PDU generated by the first PDCP entity;

As an embodiment, the act of receiving the first PDCP PDU comprises:

receiving a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN;

wherein the first message is not used to reset the first RLC SN.

As an embodiment, the second receiver 1402 receives a first report indicating that a second PDCP SDU has not been received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

As an embodiment, the second receiver 1402 receives a first report indicating that the second PDCP SDU has not been received by indicating a fourth sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

As an example, the second transmitter 1401, transmits a second report, which is used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being non-0.

As an embodiment, the second node is a User Equipment (UE).

As an embodiment, the second node is a terminal supporting a large delay difference.

As an embodiment, the second node is a terminal supporting NTN.

As an embodiment, the second node is an aircraft.

As an embodiment, the second node is a vehicle-mounted terminal.

As an embodiment, the second node is a relay.

As an embodiment, the second node is a ship.

As an embodiment, the second node is an internet of things terminal.

As an embodiment, the second node is a terminal of an industrial internet of things.

As an embodiment, the second node is a device supporting low-latency high-reliability transmission.

For one embodiment, the second transmitter 1401 includes at least one of the antenna 420, the transmitter 418, the transmission processor 416, the multi-antenna transmission processor 471, the controller/processor 475, and the memory 476 of embodiment 4.

For one embodiment, the second receiver 1402 includes at least one of the antenna 420, the receiver 418, the receive processor 470, the multiple antenna receive processor 472, the controller/processor 475, and the memory 476 of embodiment 4.

It will be understood by those skilled in the art that all or part of the steps of the above methods may be implemented by instructing relevant hardware through a program, and the program may be stored in a computer readable storage medium, such as a read-only memory, a hard disk or an optical disk. Alternatively, all or part of the steps of the above embodiments may be implemented by using one or more integrated circuits. Accordingly, the module units in the above embodiments may be implemented in a hardware form, or may be implemented in a form of software functional modules, and the present application is not limited to any specific form of combination of software and hardware. User equipment, terminal and UE in this application include but not limited to unmanned aerial vehicle, communication module on the unmanned aerial vehicle, remote control aircraft, the aircraft, small aircraft, the cell-phone, the panel computer, the notebook, vehicle Communication equipment, wireless sensor, the network card, thing networking terminal, the RFID terminal, NB-IoT terminal, MTC (Machine Type Communication) terminal, EMTC (enhanced MTC) terminal, the data card, the network card, vehicle Communication equipment, low-cost cell-phone, low-cost panel computer, satellite Communication equipment, ship Communication equipment, wireless Communication equipment such as NTN user equipment. The base station or the system device in the present application includes, but is not limited to, a macro cell base station, a micro cell base station, a home base station, a relay base station, a gNB (NR node B) NR node B, a TRP (Transmitter Receiver Point), an NTN base station, a satellite device, a flight platform device, and other wireless communication devices.

The above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A first node for wireless communication, comprising:

a first receiver receiving a first message; re-establishing the first PDCP entity in response to receiving the first message;

a first transmitter for transmitting a first PDCP PDU, the first PDCP PDU being generated by the first PDCP entity;

2. The first node of claim 1, wherein the act of sending the first PDCP PDU comprises:

sending a first RLC PDU, wherein the first RLC PDU comprises the first PDCP PDU, and the first RLC PDU comprises a first RLC SN;

wherein the first message is not used to reset the first RLC SN.

3. The first node of claim 1, comprising:

the first transmitter transmits a second message;

4. The first node according to any of claims 1 to 3, comprising:

the first transmitter transmits a first report indicating that a second PDCP SDU is not received by indicating a second sequence number; the PDCP sequence number allocated to the second PDCP SDU before the first PDCP entity is rebuilt is a second sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

5. The first node according to any of claims 1 to 3, comprising:

the first transmitter transmits a first report indicating that a second PDCP SDU is not received by indicating a fourth sequence number; the PDCP sequence number assigned to the second PDCP SDU before the first PDCP entity is re-established is a second sequence number; the second sequence number is different from the fourth sequence number, the second sequence number being used to determine the fourth sequence number; the act of sending the first report is performed after the act of re-establishing the first PDCP entity.

6. The first node according to any of claims 1 to 5, comprising:

the first receiver receiving a second report, the second report being used to indicate a first COUNT value; the first COUNT value is a first missing COUNT value; the first COUNT value is used to determine a first initial value; an initial value of at least one state variable of the first PDCP entity is set to the first initial value after the behavior re-establishes the first PDCP entity, the first initial value being other than 0.

7. The first node according to any of claims 1 to 6, comprising:

the first message is used to indicate a first key, which the first PDCP entity uses to cipher the data included in the first PDCP PDU.

8. A second node for wireless communication, comprising:

9. A method in a first node used for wireless communication, comprising:

transmitting a first PDCP PDU generated by the first PDCP entity;

10. A method in a second node used for wireless communication, comprising:

receiving a first PDCP PDU generated by the first PDCP entity;