CN114079916A

CN114079916A - Method and equipment used for wireless communication

Info

Publication number: CN114079916A
Application number: CN202010838540.2A
Authority: CN
Inventors: 张晓博
Original assignee: Shanghai Langbo Communication Technology Co Ltd
Current assignee: Shanghai Langbo Communication Technology Co Ltd
Priority date: 2020-08-10
Filing date: 2020-08-19
Publication date: 2022-02-22
Anticipated expiration: 2040-08-19
Also published as: CN114079916B

Abstract

A method and apparatus for wireless communication includes receiving a first MAC PDU group comprising a first message, the first MAC PDU group comprising at least one MAC PDU, a MAC header of each MAC PDU in the first MAC PDU group comprising at least partial bits of a first old identity and at least partial bits of a second old identity, the first message comprising a first new identity, use of the first new identity being used to trigger decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity; transmitting a second group of MAC PDUs using a first new identity, the second group of MAC PDUs including at least one MAC PDU, a MAC header of each MAC PDU in the second group of MAC PDUs including at least a portion of bits of the first new identity; by determining the first key identity and the second key identity, the reliability is improved, and risks in communication are avoided.

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 transmission method and apparatus for improving system efficiency, optimizing resource utilization, reducing service interruption, improving service continuity, enhancing reliability, and better security and privacy protection in wireless communication.

Background

In the future, the application scenes of the wireless communication system are more and 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 Radio interface (NR) technology (or fine Generation, 5G) is decided over 72 sessions of 3GPP (3rd Generation Partner Project) RAN (Radio Access Network), and standardization Work on NR is started over WI (Work Item) where NR passes through 75 sessions of 3GPP RAN.

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, a telescopic system structure, high-efficiency non-access layer information processing, lower service interruption and disconnection rate, higher safety and privacy, for low power consumption support, which is for normal communication of base stations and user equipments, for reasonable scheduling of resources, the method has important significance for balancing system load, can be said to be high throughput rate, meets Communication requirements of various services, improves spectrum utilization rate, and improves the quality of service, and is essential for eMBBs (enhanced Mobile BroadBand), URLLC (Ultra Reliable Low Latency Communication) or eMTCs (enhanced Machine Type Communication). Meanwhile, in IIoT (Industrial Internet of Things, Device to Device) in V2X (Vehicular to X), communication between devices in unlicensed spectrum, user communication quality monitoring, Network planning optimization, Non-terrestrial Network (NTN) in TN (terrestrial Network communication), Dual connectivity (Dual connectivity) system in wireless resource management and codebook selection of multiple antennas, main link communication or sub-link communication in signaling design, neighborhood management, traffic management, and beamforming, and transmission modes of information are classified into broadcast and unicast, and both transmission modes are indispensable to 5G systems 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 a variety of communication scenarios, in the UE-to-UE communication scenario, reliable link establishment and maintenance are involved, address management configuration is involved, coordination between different layers is involved, and security problems are generated due to the fact that in the UE-to-UE communication, especially in the communication outside the coverage of a serving cell, due to the lack of management of a central node, security aspects such as authentication privacy between two UEs are more vulnerable, for example, a listener attempts to grasp communication conditions of a user or a certain application, privacy information such as geographical location information, and the like by associating a temporary identity with a long-term identity (for example, the identity of the user). One possible solution is therefore to update the parameters of the UE periodically or at certain intervals, which parameters include the identity information of the UE, parameters related to the security algorithms of the UE, etc. An important problem to be dealt with in this way is that the updated identities and parameters, in particular the parts of the plaintext transmission, are preferably updated simultaneously, otherwise the listener may use the results of a previous interception to associate the updated identity with the identity or parameter before updating via the un-updated identity or parameter as a springboard, thereby rendering the update meaningless. Since the updating of the identity involves the flow of the control plane and the transmission of the data is the behavior of the user plane, there is independence between the two, and the updating of the identity preferably does not affect the sending of the data, in the updating of the identity, both the receiving and sending directions may not be prepared at the same time, and the identities and parameters involve different layers and entities, some data may already use some old parameters, but the sending needs to start using new identities and parameters, which causes new privacy problems and complicates the whole problem. These are all issues faced by inter-UE communication, especially relating to sidelink communication, and are of particular concern for security-related services such as v2x service or prose (proximity security) service. In order to further improve privacy, improve security, avoid the user to receive the tracking, this 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 group of MAC PDUs, the first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message comprising a first new identity, the use of which is used to trigger the decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

transmitting a second group of MAC PDUs using a first new identity, the second group of MAC PDUs including at least one MAC PDU, a MAC header of each MAC PDU in the second group of MAC PDUs including at least a portion of bits of the first new identity;

wherein the first message is a PC5-S message, and the first old identity, the second old identity, and the first new identity are each a link layer identity; the first RLC entity is an RLC entity of an RB used by the second MAC PDU group, before the first new identity is used, the first RLC entity has a first RLC SDU group to be transmitted, the first RLC SDU group carries a first PDCP PDU group, the first PDCP PDU group includes at least one PDCP PDU, headers of all PDCP PDUs in the first PDCP PDU group include a first key identity, the first key identity is used to identify a first key, and the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group; the first RLC entity performing a first operation on the first set of RLC SDUs before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity is different from the first key identity.

As an embodiment, the problem to be solved by the present application includes: when communication is carried out between UE, especially to sidelink communication, the identity of the user needs to be updated from time to ensure the security, the updating of the identity of the user can happen at any time, and the updating of the identity and the sending of data are independent; the updating of the identity may comprise a plurality of identities and a plurality of parameters which need to be updated simultaneously, especially at the sending end, if new and old identities or a mixture of parameters occur within one PDU and are transmitted in clear text, it is possible for the listener to associate the new and old identities, thereby posing a security, including privacy, risk. However, the identities and parameters involved are used by different layers and entities, respectively, and it is easy to generate asynchronism, for example, data buffered in the RLC entity or data waiting for retransmission are generated before, including old parameters, and when the data are transmitted through the MAC layer, if new identities are given, the data pose a security risk. According to the method and the device, through the first operation, the data in the RLC entity can meet the transmission requirement of a new identity or a new parameter, and therefore safety risks are avoided.

As an example, the benefits of the above method include: the RLC layer needs to transmit or retransmit data, so that the safety risk caused by the starting of the new identity is avoided, and the privacy of the user is further guaranteed.

As an example, the peculiarities of the present application include: the MAC is Medium Access Control (MAC).

As an example, the peculiarities of the present application include: RLC is Radio Link Control (Radio Link Control).

As an example, the peculiarities of the present application include: the PDCP is a Packet Data Convergence Protocol (Packet Data Convergence Protocol).

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

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

As an example, the peculiarities of the present application include: the RB is a Radio Bearer.

As an example, the peculiarities of the present application include: the SRB is a Signaling Radio Bearer.

As an example, the peculiarities of the present application include: DRB is Data Radio Bearer.

As an example, the peculiarities of the present application include: PC5-S is the signaling for the PC5 interface.

In particular, according to an aspect of the present application, in response to receiving the first message, a second message is sent, the second message comprising a second new identity, the use of the second new identity being used to trigger the decommissioning of the second old identity; the second new identity is a link layer identity;

receiving a third message, the third message used to acknowledge the second message; the second message and the third message are both PC5-S messages.

Specifically, according to an aspect of the present application, the performing the first operation includes setting, by the first RLC entity, the first key identity included in the header of the PDCP PDU in all the first PDCP PDU groups as the second key identity.

Specifically, according to an aspect of the present application, the action first operation includes that the first RLC entity clears the first RLC SDU group.

Specifically, according to an aspect of the present application, a third PDCP PDU is received, where the third PDCP PDU includes at least part of bits of PDCP PDUs in the first PDCP PDU group, and a header of the third PDCP PDU includes the second critical identity. Specifically, according to an aspect of the present application, the acting a first operation includes the first RLC entity performing a re-establishment.

Specifically, according to an aspect of the present application, a fourth PDCP PDU is received, wherein the fourth PDCP PDU includes at least a part of bits of the first PDCP PDU; a header of the fourth PDCP PDU includes the second key identity.

As an embodiment, the first node is triggered to send an RLC status report by the old identity being updated to the new identity.

As an embodiment, the first node is triggered to send a PDCP status report by the old identity being updated to the new identity.

As an embodiment, the updating of the old identity to the new identity comprises a use of the old identity.

As an embodiment, the updating of the first old identity to the first new identity comprises receiving the third message.

Specifically, according to an aspect of the present application, the action first operation includes that the first RLC entity sends a third RLC PDU, where the third RLC PDU includes at least a part of bits of RLC SDUs in the first RLC SDU group; a header of a MAC PDU carrying the third RLC PDU includes at least a portion of bits of the first old identity and at least a portion of bits of the second old identity.

As an embodiment, the transmitting of the third RLC PDU is performed after the third message is received.

Specifically, according to an aspect of the present application, after the third message is received, a header of any PDCP PDU sent by the PDCP entity corresponding to the first RLC entity includes the second key identity and does not include the first key identity; when the third message is received, the header of a PDCP PDU included in a fourth RLC PDU sent by the first RLC entity includes the first key identity; a header of a MAC PDU carrying the fourth RLC PDU includes at least a portion of bits of the first legacy identity and at least a portion of bits of the second legacy identity; when the first new identity is used, a header of a PDCP PDU included in any RLC PDU sent by the first RLC entity includes the second critical identity and does not include the first critical identity.

Specifically, according to an aspect of the present application, after the first RLC entity completes sending the first RLC SDU group, the first RLC entity reports to a higher layer that the PDCP PDU including the first key identity has been sent.

Specifically, according to an aspect of the present application, after the third message is received, the first node starts a third timer, a header of any MAC PDU sent after the third timer expires does not include the first old identity nor the second old identity, and a header of a PDCP PDU included in any MAC PDU sent after the third timer expires includes the second critical identity and does not include the first critical identity.

As an embodiment, before the third timer expires and the first RLC entity owns the RLC SDU to be transmitted carrying the first key identity, the first new identity is not used.

As an example, the benefits of the above approach include: after the first node receives the indication of the third message, the first node does not start a new identity, but first tries to transmit the previously stored RLC SDU including the first key identity, and then starts the new identity, which is favorable for ensuring the continuity of data transmission; while also immediately stopping the use of the first critical identity when a new identity has to be enabled, thereby also ensuring privacy.

Specifically, according to an aspect of the present application, the first action is related to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is an SRB, the first action is that the first RLC entity clears the first RLC SDU group, or the first action is that the first RLC entity performs re-establishment; when the RB used by the first RLC SDU group is a DRB, the first operation is that the first RLC entity sets the first key identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second key identity.

Specifically, according to an aspect of the present application, a PDCP entity associated with the first RLC entity transmits a second PDCP PDU; the PDCP PDU includes a first PDCP SDU; the first PDCP PDU group carries the first PDCP SDU, and the head of the second PDCP PDU comprises the second key identity and does not comprise the first key identity.

Specifically, according to an aspect of the present application, as a response to the first RLC entity performing re-establishment, a first signaling is sent, where the first signaling instructs a receiver of the second MAC PDU group to re-establish an RLC entity of an RB used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs.

Specifically, according to an aspect of the present application, a second signaling is sent, where the second signaling instructs the receiver of the second MAC PDU group to re-establish the RLC entity of the RB used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs;

receiving third signaling, the third signaling being used to confirm the second signaling, the first RLC entity performing a re-establishment in response to receiving the third signaling.

In particular, according to an aspect of the present application, a MAC entity associated with both the first old identity and the second old identity is reset.

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.

Specifically, 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:

transmitting a first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message comprising a first new identity, the use of which is used to trigger the decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

receiving a second group of MAC PDUs using a first new identity, the second group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the second group of MAC PDUs comprising at least part of the bits of the first new identity;

wherein the first message is a PC5-S message, and the first old identity, the second old identity, and the first new identity are each a link layer identity; the first RLC entity is an RLC entity of a sending end of the used RB of the second MAC PDU group, before the first new identity is used, the first RLC entity has a first RLC SDU group to be transmitted, the first RLC SDU group carries a first PDCP PDU group, the first PDCP PDU group includes at least one PDCP PDU, headers of all PDCP PDUs in the first PDCP PDU group include a first key identity, the first key identity is used to identify a first key, and the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group; the first RLC entity performing a first operation on the first set of RLC SDUs before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity is different from the first key identity.

In particular, according to an aspect of the present application, a second message is received, the second message being used in response to the first message, the second message comprising a second new identity, the use of the second new identity being used to trigger the decommissioning of the second old identity; the second new identity is a link layer identity;

sending a third message, the third message used to acknowledge the second message; the second message and the third message are both PC5-S messages.

Specifically, according to an aspect of the present application, a third PDCP PDU is sent, where the third PDCP PDU includes at least part of bits of PDCP PDUs in the first PDCP PDU group, and a header of the third PDCP PDU includes the second key identity. Specifically, according to an aspect of the present application, the acting a first operation includes the first RLC entity performing a re-establishment.

Specifically, according to an aspect of the present application, a fourth PDCP PDU is transmitted, wherein the fourth PDCP PDU includes at least a part of bits of the first PDCP PDU; a header of the fourth PDCP PDU includes the second key identity. Specifically, according to an aspect of the present application, the first action is related to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is an SRB, the first action is that the first RLC entity clears the first RLC SDU group, or the first action is that the first RLC entity performs re-establishment; when the RB used by the first RLC SDU group is a DRB, the first operation is that the first RLC entity sets the first key identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second key identity.

Specifically, according to an aspect of the present application, after the third message is received, a header of any PDCP PDU sent by the PDCP entity corresponding to the first RLC entity includes the second key identity and does not include the first key identity; when the third message is received, the header of a PDCP PDU included in a fourth RLC PDU sent by the first RLC entity includes the first key identity; a header of a MAC PDU carrying the fourth RLC PDU includes at least a portion of bits of the first legacy identity and at least a portion of bits of the second legacy identity; when the first new identity is used, a header of a PDCP PDU included in any RLC PDU sent by the first RLC entity includes the second critical identity and does not include the first critical identity. Specifically, according to an aspect of the present application, after the third message is sent, a header of any PDCP PDU sent by a PDCP entity of an RB used by the first MAC PDU group includes the second critical identity and does not include the first critical identity; when the third message is sent, the RLC entity corresponding to the RB used by the first MAC PDU group owns a second RLC SDU group to be transmitted, where a header of a PDCP PDU included in the second RLC SDU includes the first key identity and does not include the second key identity; and when the third message is sent, at least one RLC SDU in the second RLC SDU group is sent, and a header of a MAC PDU carrying the at least one RLC SDU in the second RLC SDU group includes at least part of bits of the first old identity and at least part of bits of the second old identity.

As an embodiment, after the third message is sent, if the RLC entity corresponding to the RB used by the first MAC PDU group does not include the RLC SDU with the first key identity, the first new identity is immediately enabled; if the RLC entity corresponding to the RB used by the first MAC PDU group possesses the RLC SDU comprising the first key identity, the first new identity is enabled after a time window;

as a sub-embodiment of this embodiment, when the first new identity is enabled, the header of any MAC PDU sent by the second node includes at least part of the bits of the first new identity.

Specifically, according to an aspect of the present application, a PDCP entity of a transmitting end associated with the first RLC entity transmits a second PDCP PDU; the PDCP PDU includes a first PDCP SDU; the first PDCP PDU group carries the first PDCP SDU, and the head of the second PDCP PDU comprises the second key identity and does not comprise the first key identity.

Specifically, according to an aspect of the present application, a first signaling is received, where the first signaling is a response of the first RLC entity to perform re-establishment, and the first signaling instructs the second node to re-establish an RLC entity of an RB used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs.

Specifically, according to an aspect of the present application, a second signaling is received, where the second signaling instructs the second node to re-establish an RLC entity of an RB used by the second MAC PDU group; the first new identity is used to identify the second node;

transmitting third signaling, the third signaling being used to confirm the second signaling, the first RLC entity performing a re-establishment in response to receiving the third signaling.

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

a first receiver to receive a first group of MAC PDUs, the first group of MAC PDUs including a first message, the first group of MAC PDUs including at least one MAC PDU, a MAC header of each MAC PDU in the first group of MAC PDUs including at least part of bits of a first old identity and at least part of bits of a second old identity, the first message including a first new identity, use of the first new identity being used to trigger decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

a first transmitter for transmitting a second set of MAC PDUs using a first new identity, the second set of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the second set of MAC PDUs comprising at least part of the bits of the first new identity;

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

a second transmitter to transmit a first group of MAC PDUs, the first group of MAC PDUs including a first message, the first group of MAC PDUs including at least one MAC PDU, a MAC header of each MAC PDU in the first group of MAC PDUs including at least part of bits of a first old identity and at least part of bits of a second old identity, the first message including a first new identity, use of the first new identity being used to trigger decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

a first receiver configured to receive a second set of MAC PDUs using a first new identity, the second set of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the second set of MAC PDUs comprising at least part of the bits of the first new identity;

wherein the first message is a PC5-S message, and the first old identity, the second old identity, and the first new identity are each a link layer identity; the first RLC entity is an RLC entity at a sending end of an RB used by the second MAC PDU group, before the first new identity is used, the first RLC entity has a first RLC SDU group to be transmitted, the first RLC SDU group carries a first PDCP PDU group, the first PDCP PDU group includes at least one PDCP PDU, headers of all PDCP PDUs in the first PDCP PDU group include a first key identity, the first key identity is used to identify a first key, and the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group; the first RLC entity performing a first operation on the first set of RLC SDUs before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity is different from the first key identity.

As an example, compared with the conventional scheme, the method has the following advantages:

in the communication from the UE to the UE, the privacy of the user needs to be ensured, the user is prevented from being tracked, the possible safety risk in the process of updating the identity of the user is avoided, and meanwhile, the experience of the user for receiving the service is not influenced by the updating of the identity of the user; since the various identities and related parameters are used by different layers or entities, in conventional approaches, data using partially pre-updated identities or parameters may be sent with the new identity or sent again, leaving a chance for a listener, creating a security risk. The method provided by the application avoids the problems by further processing the data using the old identity or the parameter through the RLC entity; particularly, when the RLC entity directly modifies the header of the RLC SDU or clears the RLC SDU and retransmits the RLC SDU by the PDCP entity, the transmission of data can be ensured to be smooth and seamless, and the user experience is not affected. Some methods proposed by the present application, which are based on the transmitting end, may not affect the reception of data, and may even be nearly transparent to the receiver of data, thus making the system very robust.

Drawings

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

FIG. 1 illustrates a flow diagram of receiving a first group of MAC PDUs, transmitting a second group of MAC PDUs, 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 present application;

FIG. 7 shows a flow diagram of a transmission according to an embodiment of the present application;

FIG. 8 shows a diagram of a MAC PDU in accordance with one embodiment of the present application;

FIG. 9 is a diagram illustrating security algorithm related domains in a PDCP PDU according to an embodiment of the present application;

figure 10 illustrates a schematic diagram of a processing apparatus for use in a first node according to one embodiment of the present application;

fig. 11 illustrates a schematic diagram of a processing device for use in a second node according to an embodiment of the 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 flowchart of receiving a first MAC PDU group and transmitting a second MAC PDU group 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 MAC PDU group in step 101; transmitting a second MAC PDU group in step 102;

wherein the first group of MAC PDUs comprises a first message, the first group of MAC PDUs comprises at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprises at least part of bits of a first old identity and at least part of bits of a second old identity, the first message comprises a first new identity, the use of which is used to trigger the decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

the first node transmitting a second group of MAC PDUs using a first new identity, the second group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the second group of MAC PDUs comprising at least part of the bits of the first new identity;

said first message is a PC5-S message, said first old identity, second old identity and said first new identity are each a link layer identity; the first RLC entity is an RLC entity of an RB used by the second MAC PDU group, before the first new identity is used, the first RLC entity has a first RLC SDU group to be transmitted, the first RLC SDU group carries a first PDCP PDU group, the first PDCP PDU group includes at least one PDCP PDU, headers of all PDCP PDUs in the first PDCP PDU group include a first key identity, the first key identity is used to identify a first key, and the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group; the first RLC entity performing a first operation on the first set of RLC SDUs before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity is different from the first key identity.

For one embodiment, the first MAC PDU group includes P MAC PDUs, where P is a positive integer.

As an embodiment, the logical channel occupied by each MAC PDU in the first MAC PDU group includes scch (sidelink Control channel) and stch (sidelink Traffic channel).

As an embodiment, the physical channel occupied by each MAC PDU in the first MAC PDU group includes a pssch (physical downlink shared channel).

As an embodiment, the first MAC PDU group is transmitted over an SL-SCH channel.

As an embodiment, the first MAC PDU group is transmitted through a sidelink (sidelink).

As one embodiment, the MAC layer is a MAC sublayer.

As an embodiment, the RLC layer is an RLC sublayer.

As an embodiment, the PDCP layer is a PDCP sublayer.

For one embodiment, the first message includes DIRECT LINK a MODIFICATION REQUEST.

For one embodiment, the first message includes DIRECT LINK MODIFICATION ACCEPT.

For one embodiment, the first message includes DIRECT LINK KEEPALIVE REQUEST.

For one embodiment, the first message includes DIRECT LINK KEEPALIVE RESPONSE.

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

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

For one embodiment, the first message includes a Direct link identifier update request.

For one embodiment, the first message includes a partial field in a Direct link identifier update request.

As an embodiment, the first message is a Direct link identifier update request.

As an embodiment, the MAC SDU of the MAC PDU in the first MAC PDU group carries the first message.

As an embodiment, the first message is carried as PDCP SDUs by one or more MAC PDUs.

For one embodiment, the Link layer includes a Link layer.

As one embodiment, the link Layer includes Layer 2.

As one embodiment, the Link layer identity includes a Link layer identifier.

As one embodiment, the Link layer identity includes a Link layer identity.

For one embodiment, the link Layer identity includes a Layer-2 ID.

As one embodiment, the link Layer identity includes a Layer 2 ID.

For one embodiment, the link layer identity includes an L2 ID.

For one embodiment, the link Layer identity comprises Layer 2 identity.

As an embodiment, the link Layer identity comprises a Layer 2 identifier.

As an embodiment, the link layer identity comprises 24 bits.

For one embodiment, each MAC PDU in the first group of MAC PDUs includes K1 bits in the first old identity, where K1 is a positive integer.

As a sub-embodiment of this embodiment, the K1 bits are the K1 most significant bits of the first old identity.

As a sub-embodiment of this embodiment, the K1 bits are the K1 least significant bits of the first old identity.

As a sub-example of this embodiment, K1 ═ 8.

As a sub-example of this embodiment, K1 ═ 16.

As a sub-embodiment of this embodiment, K1 is configured by the serving cell of the first node.

As a sub-embodiment of this embodiment, K1 is self-configured by the first node.

As a sub-embodiment of this embodiment, K1 is configured by the first node hardware curing.

As a sub-embodiment of this embodiment, K1 is configured by the sender of the first message.

As a sub-embodiment of this embodiment, the first node receives a first SCI (sidelink control information), the first SCI comprising bits of the first old identity other than the K1 bits.

For one embodiment, each MAC PDU in the first group of MAC PDUs includes K2 bits in the second old identity, where K2 is a positive integer.

As a sub-embodiment of this embodiment, the K2 bits are the K2 most significant bits of the second old identity.

As a sub-embodiment of this embodiment, the K2 bits are the K2 least significant bits of the second old identity.

As a sub-example of this embodiment, K2 ═ 8.

As a sub-example of this embodiment, K2 ═ 16.

As a sub-embodiment of this embodiment, K2 is configured by the serving cell of the first node.

As a sub-embodiment of this embodiment, K2 is self-configured by the first node.

As a sub-embodiment of this embodiment, K2 is configured by the first node hardware curing.

As a sub-embodiment of this embodiment, K2 is configured by the sender of the first message.

As a sub-embodiment of this embodiment, the first node receives a second SCI (sidelink control information), which includes bits of the second old identity other than the K2 bits.

As one embodiment, the first message includes a Source layer-2ID field, and the first new identity is the identity indicated by the Source layer-2ID field.

As an embodiment, the first old identity is immediately taken out of use after the first new identity is taken into use.

As an embodiment, the first old identity is taken out of use for a period of time after the first new identity is taken into use.

As an embodiment, the first old identity is immediately stopped for data transmission after the first new identity is used for data transmission.

As an embodiment, the first old identity stops being used for data reception immediately after the first new identity is used for data reception.

As an embodiment, sending data using the first new identity comprises setting a DST field in a header of the sent MAC PDU to partial bits of the first new identity.

As an embodiment, receiving data using the first new identity includes receiving a MAC PDU with the SRC field in the header being part of the bits of the first new identity.

As an embodiment, the first new identity is used immediately after the first old identity is taken out of use.

As an embodiment, the first new identity is used for a period of time after the first old identity is decommissioned.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is used to identify a source identity of the received MAC PDU.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is used to identify a destination identity of the transmitted MAC PDU.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is used to identify the unicast link occupied by the issued MAC PDU.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the context of the unicast link occupied by the issued MAC PDU comprises the first new identity.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is used to identify a sender of the first group of MAC PDUs.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is associated to a DRB occupied by the first MAC PDU group.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: the first new identity is associated to the SRB occupied by the first MAC PDU group.

As an embodiment, the use of the first new identity in the sentence includes the following meanings: listening for a MAC PDU comprising at least part of the bits of the first new identity.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer used to identify the source identity of the received MAC PDU.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer used to identify the destination identity of the transmitted MAC PDU.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer used to identify the unicast link occupied by the transmitted MAC PDU.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the context of the unicast link occupied by the issued MAC PDU no longer includes the first old identity.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer used to identify the sender of the first group of MAC PDUs.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer associated to the DRB occupied by the first MAC PDU group.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the first old identity is no longer associated to the SRB occupied by the first MAC PDU group.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: no longer listens for a MAC PDU comprising at least part of the bits of the first old identity.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the header of the transmitted MAC PDU does not include any bits of the first old identity.

As an embodiment, the decommissioning of the sentence for the first old identity comprises the following meanings: the header of the transmitted MAC PDU does not include any bits of the first old identity nor any bits of the second old identity.

As an embodiment, the decommissioning of the sentence for the second old identity comprises the following meanings: the header of the transmitted MAC PDU does not include any bits of the first old identity nor any bits of the second old identity.

As an embodiment, the second key identity comprises K_NRP-sess ID。

As an embodiment, the second key identity is K_NRP-sess ID。

As an embodiment, the second key identity is K_NRP-sessThe identity of (c).

As an embodiment, the second key identity comprises K_NRPThe identity of (c).

As an embodiment, the first message comprises KN bits of the second key identity, where KN is a positive integer.

As a sub-embodiment of this embodiment, the KN bits are the KN most significant bits of the second key identity.

As a sub-embodiment of this embodiment, the KN bits are the KN least significant bits of the second key identity.

As a sub-embodiment of this embodiment, KN is equal to 8.

As a sub-embodiment of this embodiment, KN is equal to 16.

For one embodiment, the second MAC PDU group includes Q MAC PDUs, where P is a positive integer.

As an embodiment, the logical channel occupied by each MAC PDU in the second MAC PDU group includes an scch (sidelink Control channel).

As an embodiment, the logical channel occupied by each MAC PDU in the second MAC PDU group includes stch (sidelink Traffic channel).

As an embodiment, the physical channel occupied by each MAC PDU in the second MAC PDU group includes a pssch (physical downlink shared channel).

As an embodiment, the second MAC PDU group is transmitted over a SL-SCH channel.

As an embodiment, the second MAC PDU group is transmitted through a sidelink (sidelink).

As an embodiment, the second set of MAC PDUs includes all MAC PDUs transmitted using the first new identity.

As an embodiment, the second set of MAC PDUs comprises MAC PDUs whose all MAC headers comprise the first new identity.

As an embodiment, the second set of MAC PDUs comprises all MAC headers whose DST fields comprise the MAC PDU of the first new identity.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: and the RB used by the data carried by the second MAC PDU group.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: and the RB is used for transmitting the PDCP SDU carried by the second MAC PDU group.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: and the RB used by the PDCP SDU carried by the second MAC PDU group.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: and the RB mapped by the QoS flow carried by the second MAC PDU group.

As a sub-embodiment of this embodiment, the number of RBs used for transmitting the PDCP SDU carried by the second MAC PDU group is KR, where KR is a positive integer.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: the RB used by the second MAC PDU group includes a DRB.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: the RBs used by the second MAC PDU group include SRBs.

As an example, the sentence "RB used by the second MAC PDU group" includes the following meanings: the RB used by the second MAC PDU group is an SLRB.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity included in an RB used by the second MAC PDU group.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity to which the RB used by the second MAC PDU group is mapped.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity providing an RLC bearer service to the RBs used by the second MAC PDU group.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity associated with an RB used by the second MAC PDU group.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: a corresponding RLC entity corresponding to an RB used by the second MAC PDU group.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity having the same slrb-PC5-ConfigIndex as the RB used by the second MAC PDU group.

As an example, the sentence "RLC entity of RB used by the second MAC PDU group" includes the following meanings: an RLC entity providing an RLC channel to PDCP PDUs included in the second MAC PDU group.

As a sub-embodiment of this embodiment, the RLC entity is an RLC entity of a transmitting end.

As a sub-embodiment of this embodiment, the RLC entity is an RLC entity of the first node.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes the meaning that the first RLC SDU group includes RLC SDUs in a buffer of the first RLC entity.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes the meaning that the first RLC SDU group includes unprocessed RLC SDUs of the first RLC entity.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes the meaning that the first RLC SDU group includes the RLC SDUs of the first RLC entity that are not discarded.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes the meaning that the first RLC SDU group includes RLC SDUs in a transmission buffer of the first RLC entity.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes the meaning that the first RLC SDU group includes RLC SDUs in a retransmission buffer of the first RLC entity.

As an embodiment, the sentence "the first RLC entity owns the first RLC SDU group to be transmitted" includes that the first RLC SDU group includes RLC SDUs of the first RLC entity that are not acknowledged by the counterpart as received.

For one embodiment, the first RLC entity is in AM mode.

For one embodiment, the first RLC entity is in UM mode.

As an embodiment, the content of the first operation relates to a mode in which the first RLC entity is located.

For one embodiment, the first PDCP PDU group includes KP PDCP PDUs, where KP is a positive integer.

As an embodiment, one PDCP PDU is one RLC SDU; one RLC SDU is one PDCP PDU.

As an embodiment, the sentence "the first RLC SDU group carries a first PDCP PDU group" includes the following meanings: the first RLC SDU group includes the first PDCP PDU group.

As an embodiment, the sentence "the first RLC SDU group carries a first PDCP PDU group" includes the following meanings: the first RLC SDU group corresponds to the first PDCP PDU group.

As an embodiment, a field in the header of all PDCP PDUs in the first PDCP PDU group is set to the first critical identity.

As an embodiment, the first key identity comprises K_NRP-sess ID。

As an embodiment, the first key identity is K_NRP-sess ID。

As an embodiment, the first key identity is K_NRP-sessThe identity of (c).

As an embodiment, the first key identity comprises K_NRPThe identity of (c).

As an embodiment, a header of a PDCP PDU carried by the first MAC PDU group includes the first key identity.

As an embodiment, a header of a PDCP PDU carried by at least one MAC PDU in the first MAC PDU group includes the first critical identity.

As an embodiment, the header of all PDCP PDUs in the first PDCP PDU group includes a field indicating the first key identity.

As an embodiment, the headers of all PDCP PDUs in the first PDCP PDU group do not include the second critical identity.

As an embodiment, the header of all PDCP PDUs in the first PDCP PDU group indicates the first critical identity and not the second critical identity.

As one embodiment, the first key includes K_NRP-sess。

As one embodiment, the first key includes K_NRP。

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the first key is used to generate a key used by a security algorithm applied to each PDCP PDU in the first group of PDCP PDUs.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the security algorithm applied to the first PDCP PDU group includes ciphering.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the security algorithm applied to the first PDCP PDU group includes integrity protection.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: a security algorithm applied to the first group of PDCP PDUs is applied to a load (payload) included in any one of the first group of PDCP PDUs.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the security algorithm applied to the first PDCP PDU group is applied to a MAC-I (message Authentication Code for integrity) included in any one PDCP PDU of the first PDCP PDU group.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the security algorithm applied to the first PDCP PDU group comprises ciphering, the key used for ciphering comprises NRPEK, and the first key is used to generate NRPEK.

As a sub-embodiment of this embodiment, the first node generates the NRPEK by the first key according to an internal algorithm.

As a sub-embodiment of this embodiment, the first node generates the NRPEK from the first key according to a standard algorithm.

As a sub-embodiment of this embodiment, the first node randomly selects some bits from the first key to generate the NRPEK.

As an embodiment, the sentence "the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group" includes the following meanings: the security algorithm applied to the first PDCP PDU group comprises integrity protection using a key comprising NRPIK, the first key being used to generate NRPIK.

As a sub-embodiment of this embodiment, the first node generates the NRPIK by the first key according to an internal algorithm.

As a sub-embodiment of this embodiment, the first node generates the NRPIK from the first key according to a standard algorithm.

As a sub-embodiment of this embodiment, the first node randomly selects some bits from the first key to generate the NRPIK.

As an embodiment, the first key identity is used for determining the first key uniquely.

As an embodiment, the first key identity is mapped to the first key.

As an embodiment, the second key identity is used for determining the first key uniquely.

As an embodiment, the second key identity is mapped to the first key.

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation is performed before the first new identity is used.

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation is performed before sending a MAC PDU using the first new identity.

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation is performed after determining to use a first new identity and before sending a MAC PDU using the first new identity.

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation includes the first RLC entity setting the first critical identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second critical identity.

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation includes the first RLC entity clearing the first RLC SDU group.

As a sub-embodiment of this embodiment, the behavior cleanup includes a delete (delete).

As a sub-embodiment of this embodiment, the behavior cleanup comprises a clear.

As a sub-embodiment of this embodiment, the behavior cleanup includes discard (discard).

As an embodiment, the sentence "the first RLC entity performs a first operation on the first set of RLC SDUs before the first new identity is used" includes the following meanings: the first operation includes the first RLC entity performing a re-establishment (re-establishment).

As a sub-embodiment of this embodiment, the behavior performing re-establishment comprises deleting or flushing or discarding the first RLC SDU.

As an embodiment, the sentence said "when the first new identity is used, the header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity being different from the first key identity "includes the following meanings: transmitting the second set of MAC PDUs using the first new identity.

As an embodiment, the sentence said "when the first new identity is used, the header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity being different from the first key identity "includes the following meanings: the header of the PDCP PDUs included or carried by the second MAC PDU group sent using the first new identity includes the second critical identity and not the first critical identity.

As an embodiment, the sentence said "when the first new identity is used, the header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity being different from the first key identity "includes the following meanings: the DST field of the second MAC PDU includes the first new identity, and a header of a PDCP PDU included or carried by the second MAC PDU group includes the second key identity but not the first key identity.

As an embodiment, after the first operation is performed, a header of a PDCP PDU included in any RLC SDU to be transmitted, which is owned by the first RLC entity, includes only the second critical identity and does not include the first critical identity.

As one embodiment, the first message includes an Application layer identity (Application layer ID).

As a sub-embodiment of this embodiment, the first message includes a Source user info field, which indicates an application layer identity.

For one embodiment, the first message includes an IP address.

As a sub-embodiment of this embodiment, the first message includes a Source link local IPv6 address field, where the Source link local IPv6 address field indicates an IP address.

As a sub-embodiment of this embodiment, the IP address is a new IP address.

As an embodiment, a PDCP entity associated with the first RLC entity transmits a second PDCP PDU; the PDCP PDU includes a first PDCP SDU; the first PDCP PDU group carries the first PDCP SDU, and the head of the second PDCP PDU comprises the second key identity and does not comprise the first key identity.

As a sub-embodiment of this embodiment, the sentence "the PDCP entity associated with the first RLC entity transmits the second PDCP PDU" includes that the PDCP entity associated with the first RLC entity transmits the second PDCP PDU to a lower layer (lower layer).

As a sub-embodiment of this embodiment, the PDCP entity associated with the first RLC entity sends a third PDCP PDU group, where the PDCP SDUs included in the third PDCP PDU group are the same as the PDCP SDUs included in the first PDCP PDU group.

As a sub-embodiment of this embodiment, the second PDCP PDU includes a second PDCP SDU and a second SN (sequence number ), the first PDCP PDU group includes a 1a PDCP PDU, the 1a PDCP PDU includes the second PDCP SDU, and the 1a PDCP PDU includes the second SN.

As a sub-embodiment of this embodiment, the PDCP entity associated with the first RLC entity retransmits lower unacknowledged PDCP SDUs using the second critical identity.

As a sub-embodiment of this embodiment, the PDCP entity associated with the first RLC entity transmits PDCP SDUs to which SN numbers have been assigned using the second key identity.

As a sub-embodiment of this embodiment, the PDCP entity associated with the first RLC entity uses the second key identity to transmit PDCP SDUs that have been assigned SN numbers and are not handed to a lower layer.

As an embodiment, the action first operation relates to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is SRB, the action first operation is that the first RLC entity clears the first RLC SDU group, or the action first operation is that the first RLC entity performs re-establishment; when the RB used by the first RLC SDU group is a DRB, the first operation is that the first RLC entity sets the first key identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second key identity.

As an embodiment, the behavior first operation relates to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is an SRB, the behavior first operation is that the first RLC entity clears the first RLC SDU group; the behavior first operation is that the first RLC entity performs re-establishment when an RB used by the first RLC SDU group is a DRB.

As an embodiment, the behavior first operation relates to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is a DRB, the behavior first operation is that the first RLC entity clears the first RLC SDU group; when the RB used by the first RLC SDU group is an SRB, the behavior first operation is that the first RLC entity performs re-establishment.

As an embodiment, the behavior first operation relates to a mode of the first RLC entity, and when the first RLC entity is in AM, the behavior first operation is that the first RLC entity clears the first RLC SDU group; when the first RLC entity is in the UM mode, the first operation is that the first RLC entity sets the first key identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second key identity, or the first operation is that the first RLC entity performs re-establishment.

As an embodiment, the first action is related to a mode of the first RLC entity, and when the first RLC entity is in AM, the first action is that the first RLC entity clears the first RLC SDU group, or the first action is that the first RLC entity sets the first key identity included in a header of PDCP PDUs in all the first PDCP PDU groups as the second key identity; the behavior first operation is that the first RLC entity performs re-establishment when the first RLC entity is in UM mode.

As an embodiment, the behavior first operation is related to a mode of the first RLC entity, the behavior first operation is that the first RLC entity clears the first RLC SDU group when the first RLC entity is in AM, and the behavior first operation is that the first RLC entity performs re-establishment when the first RLC entity is in UM mode.

As an embodiment, the behavior first operation is related to a mode of the first RLC entity, the behavior first operation is that the first RLC entity clears the first RLC SDU group when the first RLC entity is in UM, and the behavior first operation is that the first RLC entity performs re-establishment when the first RLC entity is in AM mode.

As an embodiment, the benefits of the above approach include that for SRBs, it can be guaranteed that the signaling is up-to-date; for the DRB, continuity of data transmission can be guaranteed.

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 (5GSystem)/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 b (gNB)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/EPC 210. 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. Those skilled in the art may also refer to UE201 as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communication 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 domain)/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/EPC 210. In general, the MME/AMF/SMF211 provides bearer and connection management. All user IP (Internet protocol) packets are transported through the S-GW/UPF212, which S-GW/UPF212 itself is connected to the P-GW/UPF 213. 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. In a network using a 5G core network, to support v2x, functions required by the core network may be implemented by a PCF (Policy Control Function). The ProSe application server 230 has the functions of storing EPC ProSe subscriber identities, mapping between application layer subscriber identities and EPC ProSe subscriber identities, allocating ProSe restricted code suffix pools, etc. In the 5G core network, functions similar to those provided by the ProSe function 250 may be implemented in pcf (policy Control function), or may be implemented alone or in combination with a V2X Application Server (V2X Application Server). For V2X traffic, in a 5G core network, functions similar to the ProSe Application Server 230 may be implemented by a V2X Application Server (V2X Application Server). In 5GC, the ProSe function 250 can be implemented within PCF. In 5GS, the ProSe application server 230 may be implemented within the AF of 5 GC.

As an embodiment, the UE201 and the UE241 are connected through a Reference Point (Reference Point) of the PC 5.

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 with the ProSe application of the UE201 and the ProSe application of the UE241 through a PC1 reference point, respectively.

As an embodiment, the first node and the second 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 the present 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 radio link from the UE241 to the NR node B is an uplink.

As an embodiment, the radio link from the NR node B to the UE241 is the downlink.

As an embodiment, the UE201 supports relay transmission.

As an embodiment, the UE241 supports relay transmission.

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 a radio protocol architecture for a user plane 350 and a control plane 300, fig. 3 showing the radio protocol architecture for the control plane 300 between a first node (UE, satellite or aircraft in a gNB or NTN) and a second node (gNB, satellite or aircraft in a UE or NTN), or 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 PHY 301. 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 PHY 301. 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. The RRC (Radio Resource Control) sublayer 306 in layer 3 (layer L3) 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 (PC5Signaling Protocol ) sublayer 307 is responsible for processing 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.).

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

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

As an embodiment, the first MAC PDU group in this application is generated in the MAC302 or the MAC 352.

As an embodiment, the second MAC PDU group in this application is generated in the MAC302 or the MAC 352.

As an embodiment, the first message in this application is generated in the PC 5-S307.

As an embodiment, the second message in this application is generated in the PC 5-S307.

As an example, the third message in this application is generated in the PC 5-S307.

As an embodiment, the first signaling in this application is generated in the PC5-S307 or RRC306 or MAC302 or MAC352 or RLC303 or RLC 353.

As an embodiment, the second signaling in this application is generated in the PC5-S307 or RRC306 or MAC302 or MAC352 or RLC303 or RLC 353.

As an embodiment, the third signaling in this application is generated in the PC5-S307 or RRC306 or MAC302 or MAC352 or RLC303 or RLC 353.

For one embodiment, the first RLC entity corresponds to RLC303 or RLC 353.

For one embodiment, the first PDCP PDU group is generated in the PDCP304 or PDCP 354.

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 communication 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 layer L2. 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 processing 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 transmit 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 stream from the 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 functionality 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 implements header compression, encryption, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocation, implementing 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 communications 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 functionality of the L1 layer. Controller/processor 475 implements the 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 group of MAC PDUs, the first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message requesting the use of a first new identity, the use of the first new identity being used to trigger the decommissioning of the first old identity; maintaining the first timer; sending a second message in response to receiving the first message, the second message indicating use of a second new identity, the use of the second new identity being used to trigger decommissioning of the second old identity; receiving a third message, the third message used to acknowledge the second message; or, when the first timer expires, sending a fourth message indicating a third new identity, the use of which is used to trigger the decommissioning of the second old identity; wherein the act of maintaining a first timer comprises resetting the first timer in response to sending the second message; or the act of maintaining the first timer comprises resetting the first timer in response to receiving the third message; or the act of maintaining the first timer comprises suspending updating the first timer in response to sending the second message; said first message and said second message and said third message are PC5-S messages, said first old identity, said first new identity and said third new identity are each a link layer identity.

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 group of MAC PDUs, the first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message requesting the use of a first new identity, the use of the first new identity being used to trigger the decommissioning of the first old identity; maintaining the first timer; sending a second message in response to receiving the first message, the second message indicating use of a second new identity, the use of the second new identity being used to trigger decommissioning of the second old identity; receiving a third message, the third message used to acknowledge the second message; or, when the first timer expires, sending a fourth message indicating a third new identity, the use of which is used to trigger the decommissioning of the second old identity; wherein the act of maintaining a first timer comprises resetting the first timer in response to sending the second message; or the act of maintaining the first timer comprises resetting the first timer in response to receiving the third message; or the act of maintaining the first timer comprises suspending updating the first timer in response to sending the second message; said first message and said second message and said third message are PC5-S messages, said first old identity, said first new identity and said third new identity are each a link layer identity.

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: transmitting a first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message requesting the use of a first new identity, the use of the first new identity being used to trigger the decommissioning of the first old identity; a recipient of the first message maintains a first timer; in response to receiving the first message, the second message is sent, the second message indicating use of a second new identity, the use of the second new identity being used to trigger decommissioning of the second old identity; when the second message is received, sending a third message; the third message is used to acknowledge the second message; when the first timer expires, a fourth message is sent, the fourth message indicating a third new identity, the use of the third new identity being used to trigger the decommissioning of the second old identity, receiving the fourth message; wherein the act of maintaining a first timer comprises resetting the first timer in response to sending the second message; or the act of maintaining the first timer comprises resetting the first timer in response to receiving the third message; or the act of maintaining the first timer comprises suspending updating the first timer in response to sending the second message; said first message and said second message and said third message are PC5-S messages, said first old identity, said first new identity and said third new identity are each a link layer identity.

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: failing to correctly receive the first MAC PDU group; the first MAC PDU group comprises at least a first MAC PDU; transmitting a first group of MAC PDUs comprising a first message, the first group of MAC PDUs comprising at least one MAC PDU, the MAC header of each MAC PDU in the first group of MAC PDUs comprising at least part of the bits of a first old identity and at least part of the bits of a second old identity, the first message requesting the use of a first new identity, the use of the first new identity being used to trigger the decommissioning of the first old identity; a recipient of the first message maintains a first timer; in response to receiving the first message, the second message is sent, the second message indicating use of a second new identity, the use of the second new identity being used to trigger decommissioning of the second old identity; when the second message is received, sending a third message; the third message is used to acknowledge the second message; when the first timer expires, a fourth message is sent, the fourth message indicating a third new identity, the use of the third new identity being used to trigger the decommissioning of the second old identity, receiving the fourth message; wherein the act of maintaining a first timer comprises resetting the first timer in response to sending the second message; or the act of maintaining the first timer comprises resetting the first timer in response to receiving the third message; or the act of maintaining the first timer comprises suspending updating the first timer in response to sending the second message; said first message and said second message and said third message are PC5-S messages, said first old identity, said first new identity and said third new identity are each a link layer identity.

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.

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 set of MAC PDUs.

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 third message in this application.

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

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

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

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 signaling.

For one embodiment, receiver 416 (including antenna 420), receive processor 412, and controller/processor 440 are used to receive the second set of MAC PDUs.

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

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

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

For one embodiment, a transmitter 416 (including antenna 420), a transmit processor 412, and a controller/processor 440 are used to transmit the first set of MAC PDUs.

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 transmit the third message in this application.

For one embodiment, the transmitter 416 (including the antenna 420), the transmit processor 412, and the controller/processor 440 are used to transmit the third signaling.

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 the first node of the present application, U02 corresponds to the second node of the present application, and it is specifically illustrated that the sequence in the present example does not limit the signal transmission sequence and the implemented sequence in the present application, wherein the steps in F51 are optional.

For theFirst node U01Receiving a first MAC PDU group in step S5101; sending a second message in step S5102; receiving a third message in step S5103; a first operation is performed in step S5104; the second MAC PDU group is transmitted in step S5105.

For theSecond node U02Transmitting the first MAC PDU group in step S5201; receiving the second message in step S5202; transmitting the third message in step S5203; the second MAC PDU group is received in step S5204.

In embodiment 5, the first MAC PDU group comprises a first message, the first MAC PDU group comprises at least one MAC PDU, a MAC header of each MAC PDU in the first MAC PDU group comprises at least part of bits of a first old identity and at least part of bits of a second old identity, the first message comprises a first new identity, use of the first new identity is used to trigger decommissioning of the first old identity; the first message comprises at least a portion of bits of a second key identity.

In step S5105, the first node U01 sends a second group of MAC PDUs using a first new identity, the second group of MAC PDUs including at least one MAC PDU, the MAC header of each MAC PDU in the second group of MAC PDUs including at least part of the bits of the first new identity;

wherein the first message is a PC5-S message, and the first old identity, the second old identity, and the first new identity are each a link layer identity; the first RLC entity is an RLC entity of an RB used by the second MAC PDU group, before the first new identity is used, the first RLC entity has a first RLC SDU group to be transmitted, the first RLC SDU group carries a first PDCP PDU group, the first PDCP PDU group includes at least one PDCP PDU, headers of all PDCP PDUs in the first PDCP PDU group include a first key identity, the first key identity is used to identify a first key, and the first key is used to generate a key used by a security algorithm applied to the first PDCP PDU group; in step S5104, the first RLC entity performs a first operation on the first set of RLC SDUs, the performing of the first operation occurring before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the second MAC PDU group includes the second key identity and does not include the first key identity, the second key identity being used to identify the first key; the second key identity is different from the first key identity.

For one embodiment, the communication interface between the first node U01 and the second node U02 is a PC 5.

For one embodiment, the communication interface between the first node U01 and the second node U02 is Uu.

As an embodiment, the first node U01 is a UE and the second node U02 is also a UE.

As an embodiment, the first node U01 is a UE and the second node U02 is a relay.

As an embodiment, the first node U01 is a relay and the second node U02 is a UE.

For one embodiment, the first node U01 receives first physical layer signaling, the first physical layer signaling including configuration information for a first channel on which the first set of MAC PDUs are transmitted; the first physical layer signaling and any MAC PDU in the first group of MAC PDUs collectively comprise the first old identity; the first physical layer signaling and any MAC PDU in the first group of MAC PDUs collectively include the second old identity.

As a sub-embodiment of this embodiment, the first physical layer signaling includes dci (downlink Control information).

As a sub-embodiment of this embodiment, the first physical layer signaling includes sci (sidelink Control information).

As a sub-embodiment of this embodiment, the physical layer channel occupied by the first physical layer signaling includes PSCCH.

As a sub-embodiment of this embodiment, the physical layer channel occupied by the first physical layer signaling includes a PDCCH.

As a sub-embodiment of this embodiment, the first physical layer signaling includes time-frequency resource information occupied by the first MAC PDU.

As a sub-embodiment of this embodiment, the first physical layer signaling includes scheduling information of the first MAC PDU.

As a sub-embodiment of this embodiment, the first channel comprises a PDSCH.

As a sub-embodiment of this embodiment, the first channel comprises a pscch.

As a sub-embodiment of this embodiment, the configuration information of the first channel includes time-frequency resource information.

As a sub-embodiment of this embodiment, the configuration information of the first channel includes Redundancy Version (RV) information.

As a sub-embodiment of this embodiment, the configuration information of the first channel includes New Data Indication (NDI) information.

As a sub-embodiment of this embodiment, the configuration information of the first channel includes HARQ information.

As a sub-embodiment of this embodiment, the first physical layer signaling includes N1 Least Significant Bits (LSB) of the first old identity, and any MAC PDU in the first MAC PDU group includes all bits other than the N1 least significant bits of the first old identity, where N1 is an integer greater than 0.

As a sub-embodiment of this embodiment, the first physical layer signaling includes N2 Most Significant Bits (MSB) of the second old identity, and any MAC PDU in the first MAC PDU group includes all bits other than the N2 most significant bits of the second old identity, where N2 is an integer greater than 0.

As one embodiment, the second message is used to grant the request of the first message.

For one embodiment, the first message is DIRECT LINK IDENTIFIER UPDATE REQUEST.

For one embodiment, the second message is DIRECT LINK IDENTIFIER UPDATE ACCEPT.

For one embodiment, the third message is an DIRECT LINK IDENTIFIER UPDATE ACK.

As an embodiment, the first message indicates a new application layer identity and a new IP address.

As an embodiment, the first message indicates KN1 most significant bits of the second key identity.

For one embodiment, the first key identity is used for ciphering PDCP PDUs included in the first MAC PDU group received by the first node U01.

As an embodiment, the first message is sent as a payload (payload) of PDCP PDUs carried by the first MAC PDU group.

As an embodiment, the second message includes KN1 least significant bits and KN2 most significant bits of the second key identity, wherein the second key identity includes KN1+ KN2 bits.

As a sub-embodiment of this embodiment, the first message carries the KN2 most significant bits of the second key identity.

For one embodiment, the second message includes the first new identity and the second new identity.

As an embodiment, the second message includes a first application layer identity and a second application layer identity, wherein the first message includes the first application layer identity; the first application layer identity and the second application layer identity are each an application layer identity (application layer ID).

For one embodiment, the second message includes a first IP address and a second IP address; wherein the first message comprises the first IP address; the second IP address is used for transmission of higher layer data carried by the second MAC PDU group.

As a sub-embodiment of this embodiment, the higher layer data comprises IP layer data.

As an embodiment, the third message is used to acknowledge (acknowledge) the second message.

As an embodiment, the third message includes KN1 least significant bits of the second key identity.

As an embodiment, the third message includes the second new identity.

As an embodiment, the third message comprises the second application layer identity, which is used to identify the application of the first node U01 or the first node U01.

For one embodiment, the third message includes the second IP address.

As an embodiment, higher layers of the second node U02 trigger the sending of the first message.

For one embodiment, expiration of a first privacy timer (privacy timer) of the second node U02 triggers the sending of the first message.

For one embodiment, the second node U02 starts a first timer when the first message is sent, and the second node U02 retransmits the first message when the first timer expires and the second message is not received.

As a sub-embodiment of this embodiment, the second node U02 stops the first timer when the first message is received.

As a sub-embodiment of this embodiment, the first timer is T5009.

As a sub-embodiment of this embodiment, the first timer is restarted when the first message is retransmitted.

For one embodiment, the first node U01 starts a second timer when the second message is sent, and the first node U01 retransmits the second message when the second timer expires and the third message is not received.

As a sub-embodiment of this embodiment, the first node U01 stops the second timer when the third message is received.

As a sub-embodiment of this embodiment, the second timer is T5010.

As a sub-embodiment of this embodiment, the second timer is restarted when the second message is retransmitted.

As a sub-embodiment of this embodiment, the retransmitted MAC PDU carrying the second message comprises at least a part of bits of the first old identity and at least a part of bits of the second old identity.

For one embodiment, the first node U01 starts a second timer when the second message is sent, and the first node U01 sends a fourth message when the second timer expires and the third message is not received and the second message has reached a maximum number of retransmissions; the fourth message comprises a third new identity, use of the third new identity being used to trigger decommissioning of the second old identity; the first message comprises at least a portion of bits of a third key identity.

As a sub-embodiment of this embodiment, the fourth message is DIRECT LINK IDENTIFIER UPDATE REQUEST.

As a sub-embodiment of this embodiment, the fourth message is DIRECT LINK an ESTABLISHMENT REQUEST.

As a sub-embodiment of this embodiment, the fourth message is DIRECT LINK REKEYING REQUEST.

As a sub-embodiment of this embodiment, the use of the third new identity is used to trigger the decommissioning of the first old identity.

As a sub-embodiment of this embodiment, the third new identity is the second new identity.

As a sub-embodiment of this embodiment, the third key-identity is the second key-identity.

As a sub-embodiment of this embodiment, the use of the third new identity triggers the use of the third key identity.

As a sub-embodiment of this embodiment, a header of a MAC PDU carrying the fourth message comprises at least a part of bits of the first old identity and at least a part of bits of the second old identity.

As an embodiment, the first key identity included in a header of a PDCP PDU or a context (security context) used to determine a security algorithm of the PDCP PDU.

As an embodiment, a header of a MAC PDU carrying the third message comprises at least a part of bits of the first old identity and at least a part of bits of the second old identity.

As a sub-embodiment of this embodiment, the header of the MAC PDU carrying the third message does not comprise the first new identity nor the second new identity.

As an embodiment, a header of an X1 th retransmitted MAC PDU carrying the third message includes at least a part of bits of the first new identity and at least a part of bits of the second new identity; wherein X1 is a positive integer.

As a sub-embodiment of this embodiment, the header of the X1 th retransmitted MAC PDU carrying the third message does not include the first old identity nor the second old identity.

For one embodiment, expiration of a second privacy timer of the first node is used to initiate a link identity update.

As a sub-embodiment of this embodiment, the act of initiating a link identity UPDATE includes sending DIRECT LINK IDENTIFIER an UPDATE REQUEST message.

For one embodiment, the first node U01 foregoes initiating a link identity update when the second privacy timer of the first node U01 expires after the first node U01 receives the first message and before the third message is not received.

As a sub-embodiment of this embodiment, the second message is sent less than the maximum number of retransmissions.

As a sub-embodiment of this embodiment, the sending of the second message reaches a maximum number of retransmissions and the second timer has not expired.

For one embodiment, when the first node U01 receives the first message and does not receive the third message, the first node U01 maintains the second privacy timer.

As a sub-embodiment of this embodiment, the act of maintaining the second privacy timer includes resetting the second privacy timer in response to sending the second message; or the act of maintaining the second privacy timer comprises resetting the second privacy timer in response to receiving the third message; or the act of maintaining the second privacy timer comprises suspending updating the second privacy timer in response to sending the second message.

As a sub-embodiment of this embodiment, the sending of the second message reaches a maximum number of retransmissions, and the first node starts a link identity update when the second timer expires.

As an embodiment, the benefits of the above method include that the identity in the UE-to-UE communication can be updated in a timely manner, especially when the message sent by one of the parties is not received by the other.

For one embodiment, the first node U01 determines the maximum number of retransmissions of the second message according to an internal algorithm.

For one embodiment, the first node U01 determines the maximum number of retransmissions for the second message based on received network criteria.

For one embodiment, the second node U02 determines the maximum number of retransmissions of the first message according to an internal algorithm.

For one embodiment, the second node U02 determines the maximum number of retransmissions of the first message based on received network criteria.

As an example, the benefits of the above approach include: the conflict caused by the fact that two parties communicating between the UE and the UE simultaneously start the link identity updating within a certain time is avoided.

For one embodiment, the first node U01 receives second physical layer signaling, the second physical layer signaling including configuration information for a second channel, the second MAC PDU group being sent on the first channel; the second physical layer signaling and any MAC PDU in the second MAC PDU group together comprise the first new identity; the second physical layer signaling and any MAC PDU in the second group of MAC PDUs collectively comprise the second new identity.

As a sub-embodiment of this embodiment, the second physical layer signaling includes dci (downlink Control information).

As a sub-embodiment of this embodiment, the second physical layer signaling includes sci (sidelink Control information).

As a sub-embodiment of this embodiment, the physical layer channel occupied by the second physical layer signaling includes PSCCH.

As a sub-embodiment of this embodiment, the physical layer channel occupied by the second physical layer signaling includes a PDCCH.

As a sub-embodiment of this embodiment, the second physical layer signaling includes time-frequency resource information occupied by the first MAC PDU.

As a sub-embodiment of this embodiment, the second physical layer signaling includes scheduling information of the first MAC PDU.

As a sub-embodiment of this embodiment, the second channel comprises a PDSCH.

As a sub-embodiment of this embodiment, the second channel comprises a pscch.

As a sub-embodiment of this embodiment, the configuration information of the second channel includes time-frequency resource information.

As a sub-embodiment of this embodiment, the configuration information of the second channel includes Redundancy Version (RV) information.

As a sub-embodiment of this embodiment, the configuration information of the second channel includes New Data Indication (NDI) information.

As a sub-embodiment of this embodiment, the configuration information of the second channel includes HARQ information.

As a sub-embodiment of this embodiment, the second physical layer signaling includes N1 Least Significant Bit (LSB) bits of the first new identity, and any MAC PDU in the second MAC PDU group includes all bits other than the N1 least significant bit bits of the first new identity, where N1 is an integer greater than 0.

As a sub-embodiment of this embodiment, the second physical layer signaling includes N2 Most Significant Bits (MSB) of the second new identity, and any MAC PDU in the second MAC PDU group includes all bits other than the N2 most significant bits of the second new identity, where N2 is an integer greater than 0.

As an embodiment, the second MAC PDU group includes the first RLC SDU.

As an embodiment, the first RLC entity is not re-established during the handover of the first key identity to the second key identity.

As a sub-embodiment of this embodiment, the switching of the first critical identity to the second critical identity comprises the header of PDCP PDUs issued by the first node U01 only including the second critical identity and not including the first critical identity.

As a sub-embodiment of this embodiment, the first operation is that the first RLC entity sets the first key identity included in the header of the PDCP PDU in all the first PDCP PDU groups as the second key identity, or the first RLC entity clears the first RLC SDU group.

As an embodiment, during the process of switching the first key identity to the second key identity, the PDCP entity associated with the first RLC entity is not re-established.

As a sub-embodiment of this embodiment, the RB corresponding to the first RLC entity includes or corresponds to a PDCP entity associated with the first RLC entity.

As a sub-embodiment of this embodiment, the first RLC entity is an entity that provides an RLC bearer to a PDCP entity with which the first RLC entity is associated.

As a sub-embodiment of this embodiment, the PDCP entity with which the first RLC entity is associated is an entity served by the first RLC entity.

As a sub-embodiment of this embodiment, the key used by the PDCP entity with which the first RLC entity is associated is not updated.

As one embodiment, the first MAC PDU group and the second MAC PDU group use the same RB.

For one embodiment, the second node U02 transmits a third group of MAC PDUs, the transmission of the third group of MAC PDUs being performed after the second node U02 transmits the third message.

As a sub-embodiment of this embodiment, the header of each MAC PDU in the third MAC PDU group includes at least a portion of bits of the first new identity and at least a portion of bits of the second new identity.

As a sub-embodiment of this embodiment, the header of each MAC PDU in the third MAC PDU group does not include the first old identity nor the second old identity.

As a sub-embodiment of this embodiment, the second RLC entity is an RLC entity of an RB used by the third MAC PDU group, before the first new identity is used, the second RLC entity has a second RLC SDU group to be transmitted, the second RLC SDU group carries a second PDCP PDU group, the second PDCP PDU group includes at least one PDCP PDU, and headers of all PDCP PDUs in the second PDCP PDU group include the first key identity.

As a sub-embodiment of this embodiment, the second RLC entity performs a second operation on the second set of RLC SDUs before the first new identity is used; when the first new identity is used, a header of any PDCP PDU included in the third MAC PDU group includes the second critical identity and does not include the first critical identity.

As a sub-embodiment of this embodiment, the third MAC PDU group includes all MAC PDUs issued by the second node U02 using the first new identity and the second new identity.

As a sub-embodiment of this embodiment, the third MAC PDU group includes all MAC PDUs sent by the second node U02 that use at least a part of bits of the first new identity as the value of the SRC domain of the header of the MAC PDU and that use at least a part of bits of the second new identity as the value of the DST domain of the header of the MAC PDU.

As a sub-embodiment of this embodiment, the action of the second operation includes that the second RLC entity sets the first key identity included in the header of the PDCP PDU in all the second PDCP PDU groups as the second key identity.

As a sub-embodiment of this embodiment, the action second operation comprises the first RLC entity clearing the first set of RLC SDUs.

As a sub-embodiment of this embodiment, the action second operation comprises the first RLC entity performing a re-establishment.

As a sub-implementation of this embodiment, the behavior second operation relates to a type of RB used by the second RLC SDU group, and when the RB used by the second RLC SDU group is an SRB, the behavior second operation is that the second RLC entity clears the second RLC SDU group, or the behavior second operation is that the second RLC entity performs re-establishment; when the RB used by the second RLC SDU group is a DRB, the second operation is that the second RLC entity sets the first key identity included in the header of the PDCP PDU in all the second PDCP PDU groups as the second key identity.

As an example, the benefits of the above approach include: the privacy risk caused by sending RLC SDUs comprising the first critical identity of the relevant RLC entity of the second node U02 with a new link layer identity is avoided.

For one embodiment, the first node U01 deletes the first critical identity after the first node U01 receives any MAC PDU from the third set of MAC PDUs and the first node U01 still owns the first critical identity.

For one embodiment, the second node U02 deletes the first critical identity after the second node U02 receives any MAC PDU from the second set of MAC PDUs and the second node U02 still owns the first critical identity.

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, U12 corresponds to the second node of the present application, and it is specifically illustrated that the sequence in the present example does not limit the signal transmission sequence and the implemented sequence in the present application, wherein the steps in F61 are optional. Example 6 is based on example 5, and the parts of example 6 that are involved but not described in detail can be referred to in example 5.

For theFirst node U11In step S6101, a first operation is performed; transmitting a first signaling in step S6102; transmitting a second MAC PDU group in step S6103; a third MAC PDU group is received in step S6104.

For theSecond node U12Receiving the first signaling in step S6201; a second operation is performed in step S6202; receiving a second MAC PDU group in step S6203; the third MAC PDU group is transmitted in step S6204.

As an embodiment, the action first operation includes the first RLC entity clearing the first set of RLC SDUs.

As an embodiment, the action first operation includes the first RLC entity performing a re-establishment.

As an embodiment, the first signaling explicitly indicates the second operation.

For one embodiment, the first signaling comprises RRC or PC5-RRC signaling.

As an embodiment, the first signaling comprises rrcreconconfigurationsildelink.

As one embodiment, the first signaling includes SLRB-Config.

As an embodiment, the first signaling comprises SL-PDCP-ConfigPC 5.

For one embodiment, the first signaling comprises SL-RLC-ConfigPC 5.

For one embodiment, the first signaling comprises PC5-S signaling.

As an embodiment, the action second operation includes the second RLC entity clearing the second set of RLC SDUs.

As an embodiment, the action second operation includes the second RLC entity performing a re-establishment.

As an embodiment, the acting the second operation includes the second RLC entity setting the first critical identity included in the header of the PDCP PDU in all the second PDCP PDU groups as the second critical identity.

As one embodiment, the first signaling includes the second message.

As one embodiment, the first signaling implicitly indicates the second operation.

As an embodiment, the first signaling comprises a second key identity.

For one embodiment, the first signaling includes a first new identity.

As an embodiment, the first signaling comprises a second new identity.

As an embodiment, the first signaling comprises sending MAC PDUs with the first new identity and the second new identity; the second RLC entity performs the second operation when the second node U12 receives a MAC PDU including at least part of the bits of the first new identity and at least part of the bits of the second new identity.

As an embodiment, the first signaling comprises sending PDCP PDUs in the second critical identity; when the second node U12 receives PDCP PDUs including the second critical identity, the second RLC entity performs the second operation.

As an embodiment, a header of any PDCP PDU carried or carried by the second MAC PDU group includes the second key identity but not the first key identity.

As an embodiment, a header of any PDCP PDU carried or carried by the third MAC PDU group includes the second key identity but not the first key identity.

As one embodiment, the second MAC PDU group and the third MAC PDU group use the same RB.

As an embodiment, the second MAC PDU group and the third MAC PDU group use the same unicast link.

As an embodiment, the first MAC PDU group and the third MAC PDU group use the same unicast link.

As one embodiment, the first MAC PDU group and the third MAC PDU group use the same RB.

As an embodiment, the first MAC PDU group and the third MAC PDU group use different RBs.

For one embodiment, the PDCP PDUs received by the first node U11 are discarded after the first node U11 receives PDCP PDUs including a second critical identity.

For one embodiment, the PDCP PDUs received by the second node U12 are discarded after the second node U12 receives PDCP PDUs including a second critical identity.

As an embodiment, when the first node U11 deletes the first critical identity, the first node U11 discards any PDCP PDU that includes the first critical identity in the PDCP header.

As an embodiment, when the second node U12 deletes the first critical identity, the second node U12 discards any PDCP PDU that includes the first critical identity in the PDCP header.

As an embodiment, when the first operation is that the first RLC entity clears the first RLC SDU group, the first signaling instructs the second RLC entity to clear the second RLC SDU group.

As an embodiment, when the first operation is that the first RLC entity performs re-establishment, the first signaling instructs the second RLC entity to perform re-establishment.

As an embodiment, the first RLC entity performing re-establishment includes: all RLC SDUs, RLC SDU segments and RLC PDUs are discarded.

As an embodiment, the first RLC entity performing re-establishment includes: stopping and resetting all timers maintained by the first RLC entity.

As an embodiment, the first RLC entity performing re-establishment includes: all state variables are reset to initial values.

As an embodiment, when the first operation is to clear the first RLC SDU group, a segment of an RLC SDU of which a header of a PDCP PDU included in the corresponding RLC SDU includes the first critical identity is also cleared.

As an embodiment, when the first operation is to clear the first RLC SDU group, a first RLC SDU segmentation group is also cleared, where the first RLC SDU segmentation group includes RLC SDU segments to be sent of the first RLC entity, and a header of a PDCP PDU included in an RLC SDU corresponding to any one RLC SDU segment in the first RLC SDU segmentation group includes the first key identity.

As an embodiment, when the first operation is to clear the first RLC SDU group, the first RLC PDU group is also cleared; the first RLC PDU group comprises RLC PDUs to be sent of the first RLC entity; a header of a PDCP PDU included in any one of the first set of RLC PDUs includes the first key identity.

As an embodiment, the first operation includes that the first RLC entity sets the first key identity included in the header of the PDCP PDU in all the first PDCP PDU groups to be the second key identity and discards a first RLC SDU segmentation group, the first RLC SDU segmentation group includes the RLC SDU segment to be sent of the first RLC entity, and the header of the PDCP PDU included in the RLC SDU corresponding to any RLC SDU segment in the first RLC SDU segmentation group includes the first key identity.

As an embodiment, the first operation includes the first RLC entity setting the first critical identity included in the header of the PDCP PDU in all first PDCP PDU groups as the second critical identity and discarding the first RLC PDU group; the first RLC PDU group comprises RLC PDUs to be sent of the first RLC entity; a header of a PDCP PDU included in any one of the first set of RLC PDUs includes the first key identity.

Example 7

Embodiment 7 illustrates a wireless signal transmission flow chart according to an embodiment of the present application, as shown in fig. 7. In fig. 7, U21 corresponds to the first node of the present application, U22 corresponds to the second node of the present application, and it is specifically illustrated that the sequence in the present example does not limit the signal transmission sequence and the implemented sequence in the present application, wherein the steps in F71 are optional. Example 7 is based on example 5, and the parts of example 7 that are involved but not described in detail can be referred to in example 5.

For theFirst node U21Transmitting a second signaling in step S7101; receiving a third signaling in step S7102; a first operation is performed in step S7103; transmitting a second MAC PDU group in step S7104; a third MAC PDU group is received in step S7105.

For theSecond node U22Receiving the second signaling in step S7201; a second operation is performed in step S7202; transmitting the third signaling in step S7203; receiving the second MAC PDU group in step S7204; the third MAC PDU group is transmitted in step S7205.

As an embodiment, the second signaling explicitly indicates the second operation.

For one embodiment, the second signaling comprises RRC or PC5-RRC signaling.

As an embodiment, the second signaling comprises rrcreconconfigurationsildenk.

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

For one embodiment, the second signaling comprises SL-PDCP-ConfigPC 5.

For one embodiment, the second signaling comprises SL-RLC-ConfigPC 5.

For one embodiment, the second signaling comprises a SL-test list rlc.

For one embodiment, the second signaling comprises a resendabilishRLC.

As an embodiment, the second signaling comprises rrcreeconfiguration completesidelink.

As an embodiment, the second signaling includes a first logical channel identity, and a header of any MAC PDU in the second MAC PDU group includes the first logical channel identity.

As an embodiment, the third signaling includes a second logical channel identity, and a header of any MAC PDU in the third MAC PDU group includes the second logical channel identity.

As an embodiment, a header of any MAC PDU in the third MAC PDU group includes the first logical channel identity.

As an embodiment, when the first operation is that the first RLC entity clears the first RLC SDU group, the second signaling instructs the second RLC entity to clear the second RLC SDU group.

As an embodiment, when the first operation is that the first RLC entity performs re-establishment, the second signaling instructs the second RLC entity to perform re-establishment (re-establishment).

As one embodiment, the second signaling includes the second message.

As an embodiment, the third signaling includes the third message.

As an embodiment, the second signaling and the third signaling are both PC5-S signaling.

For one embodiment, the second signaling comprises an DIRECT LINK IDENTIFIER UPDATE ACCEPT message.

For one embodiment, the third signaling comprises an DIRECT LINK IDENTIFIER UPDATE ACK message.

As an embodiment, the second signaling is used to exchange the first key identity in context as the second key identity.

As an embodiment, the second signaling is used to update the first key identity in context to the second key identity.

As an embodiment, the performing of the re-establishment by the second RLC entity includes: all RLC SDUs, RLC SDU segments and RLC PDUs are discarded.

As an embodiment, the performing of the re-establishment by the second RLC entity includes: stopping and resetting all timers maintained by the first RLC entity.

As an embodiment, the performing of the re-establishment by the second RLC entity includes: all state variables are reset to initial values.

As an embodiment, when the second operation is to clear the second RLC SDU group, a segment of an RLC SDU of which a header of a PDCP PDU included in the corresponding RLC SDU includes the first key identity is also cleared.

As an embodiment, when the second operation is to clear the second RLC SDU group, the second RLC SDU segmentation group is also cleared, where the second RLC SDU segmentation group includes RLC SDU segments to be sent of the second RLC entity, and a header of a PDCP PDU included in an RLC SDU corresponding to any one RLC SDU segment in the second RLC SDU segmentation group includes the first key identity.

As an embodiment, when the second operation is to clear the second RLC SDU group, the second RLC PDU group is also cleared; the second RLC PDU group comprises RLC PDUs to be sent of the second RLC entity; a header of a PDCP PDU included in any one of the second set of RLC PDUs includes the first key identity.

As an embodiment, the second operation includes that the second RLC entity sets the first key identity included in the header of the PDCP PDU in all the second PDCP PDU groups as the second key identity and discards a second RLC SDU segmentation group, the second RLC SDU segmentation group includes an RLC SDU segment (RLC SDU segment) to be sent by the second RLC entity, and the header of the PDCP PDU included in the RLC SDU corresponding to any RLC SDU segment in the second RLC SDU segmentation group includes the first key identity.

As an embodiment, the second operation includes the second RLC entity setting the first critical identity included in the header of the PDCP PDU of all the second PDCP PDU groups as the second critical identity and discarding the second RLC PDU group; the second RLC PDU group comprises RLC PDUs to be sent of the second RLC entity; a header of a PDCP PDU included in any one of the second set of RLC PDUs includes the first key identity.

As an embodiment, the RLC SDU to be transmitted is segmented into RLC SDU segments in a transmission buffer.

As an embodiment, the RLC SDU to be transmitted is segmented into RLC SDU segments in a retransmission buffer.

Example 8

Embodiment 8 illustrates a schematic diagram of a MAC PDU according to an embodiment of the present application, as shown in fig. 8.

In embodiment 8, one MAC PDU includes one MAC Header and at least one MAC sub PDU (sub PDU); the MAC header includes a source identity, a destination identity, and other bits.

As an embodiment, the MAC PDU is transmitted on SL-SCH (SideLink Shared CHannel).

As an embodiment, the number of bits included in the MAC header is fixed.

As an embodiment, the number of bits included in the MAC header is 32.

For one embodiment, the MAC header is a SL-SCH MAC subheader (subheader).

As an embodiment, the further bits comprise 5 fields, V, R, R, R, R, the number of bits comprised being 4, 1, respectively.

As an embodiment, the source identity and the destination identity comprise 16 bits and 8 bits, respectively.

As an embodiment, the source identity in the MAC header and the destination identity in the MAC header are the SRC domain and the DST domain, respectively.

As an embodiment, each MAC sub-PDU includes one MAC sub-header and one MAC SDU, and the MAC sub-header in each MAC sub-PDU includes an LCID field (Logical Channel IDentifier), where the LCID field indicates a Channel identity of a Logical Channel corresponding to the corresponding MAC SDU.

For one embodiment, the LCID field includes 5 bits.

For one embodiment, the LCID field includes 6 bits.

As an embodiment, each MAC PDU is also allowed to include padding bits (padding).

As an embodiment, one MAC sub-PDU includes an RLC PDU.

As an embodiment, one MAC sub-PDU includes a MAC CE.

As an embodiment, the MAC PDU in fig. 8 is a MAC PDU in the first MAC PDU group in this application.

As a sub-embodiment of the above embodiment, the first MAC PDU includes at least a first MAC sub-PDU.

As an example, the MAC PDU in fig. 8 is a MAC PDU in the second MAC PDU group in this application.

As a sub-embodiment of the above embodiment, the second MAC PDU includes at least a second MAC sub-PDU.

As an example, the MAC PDU in fig. 8 is a MAC PDU in the third MAC PDU group in this application.

As an embodiment, the source identity included in the MAC PDU in fig. 8 is a part of bits of the first old identity in this application.

As an example, the destination identity included in the MAC PDU in fig. 8 is a part of bits of the second old identity in this application.

As an example, the source identity included in the MAC PDU in fig. 8 is a part of bits of the first new identity in this application.

As an embodiment, the source identity included in the MAC PDU in fig. 8 is a part of bits of the third new identity in this application.

As an example, the destination identity included in the MAC PDU in fig. 8 is a part of bits of the second new identity in this application.

Example 9

Embodiment 9 illustrates a schematic diagram of a domain related to a security algorithm in a PDCP PDU according to an embodiment of the present application, as shown in FIG. 9, the domain'K_NPR-sessThe ID "and the field" LSBs of counter "are carried by the header of the PDCP PDU; the domain "Ciphered payload" carries the encrypted payload; the domain "Ciphered MAC (if required)" carries an encrypted Message Authentication Code, and it should be specifically noted that the MAC in the domain "Ciphered MAC (if required)" is a Message Authentication Code (Message Authentication Code) instead of a Medium Access Control (Medium Access Control).

As an embodiment, a field (field) included in one PDU is a field.

As an embodiment, the field "K" in the header of any PDCP PDU included in or carried by the first MAC PDU group_NPR-sessID "is set to the first key identity.

As an embodiment, the field "K" in the header of any PDCP PDU included in or carried by the second MAC PDU group_NPR-sessID "is set to the second key identity.

As an embodiment, the field "K" in the header of any PDCP PDU included in or carried by the third MAC PDU group_NPR-sessID "is set to the second key identity.

For one embodiment, the field "LSBs of counter" indicates or corresponds to the SN (sequence number) of the PDCP PDU.

As an embodiment, the field "LSBs of counter" is the SN (sequence number) of PDCP PDUs.

As an embodiment, when the first operation is that the first RLC entity clears the first RLC SDU group, the field of 'LSBs of counter' is set to an initial value.

As an embodiment, when the first operation is that the first RLC entity clears the first RLC SDU group, the field "LSBs of counter" of a new PDCP PDU sent by the PDCP entity of the RB corresponding to the first RLC SDU is set to a specific modified value.

As a sub-embodiment of this embodiment, the specific modified value is the sum of the current value and a specified offset, modulo the maximum possible value of the field "LSBs of counter".

As a sub-implementation of this embodimentFor example, when the first operation is performed, the specific modification value satisfies (TX _ NEXT + D1) modulo2^S(ii) a Wherein, TX _ NEXT is a state variable of the PDCP entity and indicates a COUNT value of the NEXT PDCP SDU to be sent, D1 is a positive integer, S is the bit number occupied by the field 'LSBs of counter', and modulo is a modulus operation.

As a sub-embodiment of this embodiment, when the PDCP PDU comprising the second critical identity is received, the value of the field "LSBs of counter" of the header of the PDCP PDU comprising the second critical identity is used to determine at least a part of the lowest order bits of the COUNT value.

As a sub-embodiment of this embodiment, when the PDCP PDU comprising the second critical identity is received, the value of the field "LSBs of counter" of the header of the PDCP PDU comprising the second critical identity is used to determine the RCVD _ SN.

As a sub-embodiment of this embodiment, when the PDCP PDU comprising the second critical identity is received, the value of the field "LSBs of counter" of the header of the PDCP PDU comprising the second critical identity is used to determine the RCVD _ SN; where RCVD _ SN equals (LSN-D1+ 2)^S)modulo 2^SWhere LSN is the value of the field "LSBs of counter".

As an embodiment, when the first operation is that the first RLC entity sets the first critical identity included in the headers of the PDCP PDUs in all first PDCP PDU groups as the second critical identity, the value of the domain "LSBs of counter" of the xth PDCP PDU header in the first PDCP PDU group is modified to satisfy (SN1+ D1) module 2^S(ii) a Wherein, the x PDCP PDU is any PDCP PDU in the first PDCU PDU group, the value of a domain 'LSBs of counter' of the head of the x PDCP PDU before the first operation is executed is SN1, D1 is a positive integer, S is the bit number occupied by the domain 'LSBs of counter', and modulo operation is modulo operation.

As an example, the value of D1 is a fixed value.

As an embodiment, the value of D1 is explicitly determined by PC5-S signaling during the direct link setup.

As an embodiment, the value of D1 is indicated by the first message.

As an embodiment, the value of D1 is indicated by the second message.

As an embodiment, the value of D1 is indicated by the third message.

As an embodiment, the value of D1 is indicated by the first message.

As an embodiment, the value of D1 is indicated by the first signaling.

As an embodiment, the value of D1 is indicated by the second signaling.

As an embodiment, the value of D1 is indicated by the third signaling.

As an embodiment, the value of D1 is related to the second key identity, or the value of D1 is generated by the second key identity.

As an embodiment, after the first operation is performed, a value of SN included in a header of an RLC PDU transmitted by the first RLC entity is set to (TX _ Next + D2) module 2^TWherein TX _ Next is a state variable of the first RLC entity, the TX _ Next stores an SN value of a newly generated PDU, D2 is a positive integer, T is the number of bits of an SN of an RLC PDU header transmitted by the first RLC entity, and modulo is a modulo operation.

As an embodiment, the second MAC PDU group is used to carry a first RLC PDU, the SN included in the header of the first RLC PDU has a value of RSN, and when the first RLC PDU is received, the SN of the RLC SDU carried by the first RLC PDU is determined to be (RSN-D2+ 2)^T)modulo 2^S。

As an example, the value of D2 is a fixed value.

As an embodiment, the value of D2 is explicitly determined by PC5-S signaling during the direct link setup.

As an embodiment, the value of D2 is indicated by the first message.

As an embodiment, the value of D2 is indicated by the second message.

As an embodiment, the value of D2 is indicated by the third message.

As an embodiment, the value of D2 is indicated by the first message.

As an embodiment, the value of D2 is indicated by the first signaling.

As an embodiment, the value of D2 is indicated by the second signaling.

As an embodiment, the value of D2 is indicated by the third signaling.

As an embodiment, the value of D2 is related to the second key identity, or the value of D2 is generated by the second key identity.

As an embodiment, after the first operation is performed, a value of SN included in a header of an RLC PDU transmitted by the first RLC entity is set to an initial value.

As a sub-embodiment of this embodiment, the initial value is 0.

As an embodiment, after the first operation is performed, a value of a field "LSBs of counter" included in a header of a PDCP PDU sent by a PDCP of an RB corresponding to the first RLC entity is set to an initial value.

As a sub-embodiment of this embodiment, the initial value is 0.

As a sub-embodiment of this embodiment, when the first operation is to clear the first RLC SDU group, the PDCP PDUs sent by the PDCP of the RB corresponding to the first RLC entity do not include retransmitted PDCP PDUs, and the retransmitted PDCP PDUs include PDCP PDUs included in the first RLC SDU group.

As a sub-embodiment of this embodiment, when the first operation is to clear the first RLC SDU group, the PDCP PDU sent by the PDCP of the RB corresponding to the first RLC entity includes only a new PDCP PDU.

As a sub-embodiment of this embodiment, the new PDCP PDU is a PDCP PDU whose included PDCP SDUs are not transmitted to a lower layer.

As an embodiment, after the first operation is performed, a value of a field "LSBs of counter" included in a header of a PDCP PDU including any PDCP SDU to which a SN has been allocated, which is sent by a PDCP of an RB corresponding to the first RLC entity, is set to an initial value.

As a sub-embodiment of this embodiment, the initial value is 0.

As an embodiment, after the first operation is performed, a value of a field "LSBs of counter" included in a header of a PDCP PDU including any PDCP SDU to which a SN has been allocated, which is sent by a PDCP of an RB corresponding to the first RLC entity, is set to a specific modification value; wherein SN3 is the allocated SN, and SN3 is a positive integer.

As a sub-embodiment of this embodiment, the particular modified value satisfies (SN3+ D3) modulo2 after the first operation is performed^S(ii) a Wherein, TX _ NEXT is a state variable of the PDCP entity and indicates a COUNT value of the NEXT PDCP SDU to be sent, D3 is a positive integer, S is the bit number occupied by the field 'LSBs of counter', and modulo is a modulus operation.

As an example, the benefits of the above approach include: the SN in the PDCP PDU is set to have no relation with the SN in the PDCP PDU when the first old identity and the second old identity are used for communication, and the privacy performance is further improved.

As an example, the benefits of the above approach include: the SN in the RLC PDU is set to have no relation with the SN in the RLC PDU when the first old identity and the second old identity are used for communication, and privacy performance is further improved.

Example 10

Embodiment 10 illustrates a block diagram of a processing apparatus for use in a first node according to one embodiment of the present application; as shown in fig. 10. In fig. 10, a processing means 1000 in a first node comprises a first receiver 1001 and a first transmitter 1002. In the case of the embodiment 10, the following,

a first receiver 1001 receiving a first MAC PDU group comprising a first message, the first MAC PDU group comprising at least one MAC PDU, a MAC header of each MAC PDU in the first MAC PDU group comprising at least part of bits of a first old identity and at least part of bits of a second old identity, the first message comprising a first new identity, use of the first new identity being used to trigger decommissioning of the first old identity; the first message comprises at least a part of bits of a second key identity;

a first transmitter 1002 configured to transmit a second MAC PDU group using a first new identity, the second MAC PDU group comprising at least one MAC PDU, a MAC header of each MAC PDU in the second MAC PDU group comprising at least part of bits of the first new identity;

As an embodiment, in response to receiving the first message, the first transmitter 1002 sends a second message comprising a second new identity, the use of which is used to trigger the decommissioning of the second old identity; the second new identity is a link layer identity;

the first receiver 1001 receives a third message, which is used to acknowledge the second message; the second message and the third message are both PC5-S messages.

As an embodiment, the performing the first operation includes the first RLC entity setting the first key identity included in the header of the PDCP PDU in all the first PDCP PDU groups as the second key identity.

In response to the first RLC entity performing re-establishment, the first transmitter 1002 transmitting first signaling instructing a recipient of the second MAC PDU group to re-establish an RLC entity of RBs used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs.

As an embodiment, the first transmitter 1002 transmits a second signaling instructing the receiver of the second MAC PDU group to re-establish the RLC entity of the RB used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs;

the first receiver 1001 receives third signaling, which is used to confirm the second signaling, and in response to receiving the third signaling, the first RLC entity performs re-establishment.

As an embodiment, the first transmitter 1002 resets (reset) the MAC entities associated with both the first old identity and the second old identity.

As an embodiment, the action first operation includes that the first RLC entity transmits a third RLC PDU including at least a part of bits of RLC SDUs in the first RLC SDU group; a header of a MAC PDU carrying the third RLC PDU includes at least a portion of bits of the first old identity and at least a portion of bits of the second old identity.

As an embodiment, when the first receiver 1001 receives the third message, a header of any PDCP PDU sent by the PDCP entity corresponding to the first RLC entity includes the second key identity and does not include the first key identity; when the third message is received, the header of a PDCP PDU included in a fourth RLC PDU sent by the first RLC entity includes the first key identity; a header of a MAC PDU carrying the fourth RLC PDU includes at least a portion of bits of the first legacy identity and at least a portion of bits of the second legacy identity; when the first new identity is used, a header of a PDCP PDU included in any RLC PDU sent by the first RLC entity includes the second critical identity and does not include the first critical identity.

As an embodiment, after the first RLC entity completes sending the first RLC SDU group, the first RLC entity reports to a higher layer that the PDCP PDU including the first key identity has been sent.

As an embodiment, when the first receiver 1001 receives a third message, the first transmitter 1001 starts a third timer, a header of any MAC PDU sent after the third timer expires does not include the first old identity nor the second old identity, and a header of a PDCP PDU included in any MAC PDU sent after the third timer expires includes the second critical identity and does not include the first critical identity. 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 1001 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 1002 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 11

Embodiment 11 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. 11. In fig. 11, a processing means 1100 in the second node comprises a second receiver 1102 and a second transmitter 1101. In the case of the embodiment 11, however,

As an embodiment, the second receiver 1102, receives a second message, the second message being used in response to the first message, the second message comprising a second new identity, the use of the second new identity being used to trigger the decommissioning of the second old identity; the second new identity is a link layer identity;

the second transmitter 1101, which transmits a third message, the third message being used to acknowledge the second message; the second message and the third message are both PC5-S messages.

Specifically, according to an aspect of the present application, the acting a first operation includes the first RLC entity performing a re-establishment.

As an embodiment, a PDCP entity of a transmitting end associated with the first RLC entity transmits a second PDCP PDU; the PDCP PDU includes a first PDCP SDU; the first PDCP PDU group carries the first PDCP SDU, and the head of the second PDCP PDU comprises the second key identity and does not comprise the first key identity.

As an embodiment, the second receiver 1102 receives a first signaling, the first signaling being a response of the first RLC entity performing re-establishment, the first signaling instructing the second node to re-establish an RLC entity of RBs used by the second MAC PDU group; the first new identity is used to identify a recipient of the second group of MAC PDUs.

For one embodiment, the second receiver 1102 receives a second signaling instructing the second node to re-establish the RLC entity of the RB used by the second MAC PDU group; the first new identity is used to identify the second node;

the second transmitter 1101, sending a third signaling, the third signaling being used to confirm the second signaling, the first RLC entity performing a re-establishment in response to receiving the third signaling.

For one embodiment, the second transmitter 1101 resets the MAC entities associated with both the first old identity and the second old identity.

As an embodiment, when the third message is received, a header of any PDCP PDU sent by the PDCP entity corresponding to the first RLC entity includes the second key identity and does not include the first key identity; when the third message is received, the header of a PDCP PDU included in a fourth RLC PDU sent by the first RLC entity includes the first key identity; a header of a MAC PDU carrying the fourth RLC PDU includes at least a portion of bits of the first legacy identity and at least a portion of bits of the second legacy identity; when the first new identity is used, a header of a PDCP PDU included in any RLC PDU sent by the first RLC entity includes the second critical identity and does not include the first critical identity.

As an embodiment, after the second transmitter 1101 transmits the third message, a header of any PDCP PDU transmitted by a PDCP entity of an RB used by the first MAC PDU group includes the second critical identity and does not include the first critical identity; when the second transmitter 1101 transmits the third message, an RLC entity corresponding to an RB used by the first MAC PDU group owns a second RLC SDU group to be transmitted, where a header of a PDCP PDU included in the second RLC SDU includes the first key identity and does not include the second key identity; when the second transmitter 1101 transmits the third message, at least one RLC SDU in the second RLC SDU group is transmitted, and a header of a MAC PDU carrying the at least one RLC SDU in the second RLC SDU group includes at least part of bits of the first old identity and at least part of bits of the second old identity. 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 1101 includes at least one of the antenna 420, the transmitter 418, the transmit processor 416, the multi-antenna transmit processor 471, the controller/processor 475, and the memory 476 of embodiment 4.

For one embodiment, the second receiver 1102 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, network card, thing networking terminal, the RFID terminal, NB-IoT terminal, MTC (Machine Type Communication) terminal, eMTC (enhanced MTC) terminal, the data card, 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:

2. The first node of claim 1, comprising:

in response to receiving the first message, the first transmitter sending a second message, the second message comprising a second new identity, use of the second new identity being used to trigger decommissioning of the second old identity; the second new identity is a link layer identity;

receiving, by the first receiver, a third message, the third message being used to acknowledge the second message; the second message and the third message are both PC5-S messages.

3. The first node according to any of claims 1 or 2,

the action first operation includes that the first RLC entity sets the first key identity included in the header of the PDCP PDU in all the first PDCP PDU groups as the second key identity.

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

the action first operation includes the first RLC entity clearing the first RLC SDU group.

5. The first node according to any of claims 1 to 4,

the behavior first operation includes the first RLC entity performing a re-establishment.

6. The first node according to any of claims 1 to 3,

the behavior first operation is related to a type of RB used by the first RLC SDU group, and when the RB used by the first RLC SDU group is an SRB, the behavior first operation is that the first RLC entity clears the first RLC SDU group, or the behavior first operation is that the first RLC entity performs re-establishment; when the RB used by the first RLC SDU group is a DRB, the first operation is that the first RLC entity sets the first key identity included in the headers of the PDCP PDUs in all the first PDCP PDU groups as the second key identity.

7. The first node of claim 4,

a PDCP entity associated with the first RLC entity transmits a second PDCP PDU; the PDCP PDU includes a first PDCP SDU; the first PDCP PDU group carries the first PDCP SDU, and the head of the second PDCP PDU comprises the second key identity and does not comprise the first key identity.

8. A second node for wireless communication, comprising:

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

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