Communication method and apparatus, storage medium, and program product

Abstract

Provided are a communication method and apparatus, a storage medium, and a program product, relating to the technical field of communications. The method comprises: a first relay terminal acquires an identifier of a remote terminal, the remote terminal being communicatively connected to an access network device by means of the first relay terminal; sends the identifier of the remote terminal to the access network device; and receives a local identifier of the remote terminal from the access network device.

Description

Communication methods, devices, storage media and software products

[0001] This disclosure claims priority to Chinese patent application No. 202411598370.X, filed on November 8, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of communication technology, and in particular to a communication method, apparatus, storage medium, and program product. Background Technology

[0003] The user equipment to network (U2N) relay, as specified in Release 17 and Release 18 of the 3GPP standard protocol, allows network coverage to be extended to remote terminals, but only through a single relay terminal within the coverage area. Given the relatively short distances of sidelinks (SLs), this single-hop approach clearly has limitations. Using multi-hop relays can provide a more reasonable coverage extension for U2N relays. Summary of the Invention

[0004] Firstly, a communication method is provided, applied to a first relay terminal, comprising:

[0005] Obtain the identity of the remote terminal; here, the remote terminal communicates with the access network equipment through the first relay terminal;

[0006] Send the remote terminal's identity identifier to the access network equipment;

[0007] Receive the local identifier of the remote terminal from the access network device.

[0008] Secondly, a communication method is provided for use on a remote terminal, including:

[0009] Send a second message to the access network device, the second message being used to request a connection with the access network device;

[0010] Receive third information from the access network device; the third information is used to establish a connection with the remote terminal.

[0011] Thirdly, a communication method is provided, applied to access network equipment, including:

[0012] The remote terminal receives the identity identifier of the remote terminal sent by the first relay terminal, and the remote terminal communicates and connects with the access network equipment through the first relay terminal;

[0013] Send the local identifier of the remote terminal to the access network equipment.

[0014] Fourthly, a communication device is provided for use in a first relay terminal, comprising:

[0015] The acquisition unit is used to acquire the identity identifier of the remote terminal; here, the remote terminal communicates with the access network device through the first relay terminal.

[0016] The sending unit is used to send the identity identifier of the remote terminal to the access network equipment.

[0017] The acquisition unit is also used to receive the local identifier of the remote terminal from the access network device.

[0018] Fifthly, a communication device is provided for use in a remote terminal, comprising:

[0019] The sending unit is used to send second information to the access network device, the second information being used to request a connection with the access network device;

[0020] The receiving unit is used to receive third information from the access network device, which is used to establish a connection with the remote terminal.

[0021] Sixthly, a communication device is provided for use in access network equipment, comprising:

[0022] The receiving unit is used to receive the identity identifier of the remote terminal sent by the first relay terminal. The remote terminal communicates with the access network equipment through the first relay terminal.

[0023] The sending unit is used to send the local identifier of the remote terminal to the access network equipment.

[0024] A seventh aspect provides a communication device comprising: a processor and a memory; the memory and the processor being coupled; the memory being used to store instructions executable by the processor; the processor being configured to execute instructions such that the communication device performs the method provided by any one of the first to third aspects described above.

[0025] Eighthly, a computer-readable storage medium is provided that stores computer instructions, which, when executed on a computer, cause the computer to perform the methods provided by any one of the first to third aspects described above. In some embodiments, the computer-readable storage medium includes a non-transitory computer-readable storage medium.

[0026] Ninth aspect, a computer program product comprising computer instructions, which, when executed on a computer, cause the computer to perform the method provided by any one of the first to third aspects described above. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments of this disclosure will be briefly described below. Obviously, the drawings described below are merely drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings.

[0028] Figure 1 is a multi-hop sidelink relay scenario diagram provided according to an embodiment of the present disclosure.

[0029] Figure 2 is a structural diagram of a communication system provided according to an embodiment of the present disclosure.

[0030] Figure 3 is a flowchart of a communication method provided according to an embodiment of the present disclosure.

[0031] Figure 4 is a flowchart of another communication method provided according to an embodiment of the present disclosure.

[0032] Figure 5 is a flowchart of another communication method provided according to an embodiment of the present disclosure.

[0033] Figure 6 is a diagram illustrating the RRC connection establishment process of a multi-hop remote terminal according to an embodiment of the present disclosure.

[0034] Figure 7 is a block diagram of a communication device provided according to an embodiment of the present disclosure.

[0035] Figure 8 is a block diagram of another communication device provided according to an embodiment of the present disclosure.

[0036] Figure 9 is a block diagram of another communication device provided according to an embodiment of the present disclosure.

[0037] Figure 10 is a block diagram of a communication device provided according to an embodiment of the present disclosure. Detailed Implementation

[0038] To enable those skilled in the art to better understand the technical solutions of the embodiments of this disclosure, the technical solutions of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0039] Unless the context otherwise requires, throughout the specification and claims, the term "comprise" and other forms such as the third-person singular "comprises" and the present participle "comprising" are interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0040] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0041] In this disclosure, the terms "exemplarily" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplarily" or "for example" in this disclosure should not be construed as being more preferred or advantageous than other embodiments or designs. Rather, the use of the terms "exemplarily" or "for example" is intended to present the relevant concepts in a specific manner.

[0042] In addition, the use of “based on” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0043] The U2N relay protocol, as specified in Releases 17 and 18 of the 3GPP standard protocol, allows network coverage to be extended to remote terminals, but only through a single relay terminal within the coverage area. Considering the relatively short distance of sidelinks, this single-hop approach clearly has limitations. Using multi-hop relays can provide a more reasonable coverage extension for U2N relays. Extending single-hop U2N relays to multi-hop U2N relays will open up a variety of new application scenarios. For example, in scenarios such as factory sensors and smart metering, IoT devices in disadvantageous deployment locations can be connected; furthermore, even if the companion smartphone of a smartwatch is out of coverage, the smartwatch can still benefit from establishing a connection by connecting to the network through only another UE.

[0044] Figure 1 illustrates a multi-hop sidelink relay scenario according to an embodiment of this disclosure. Referring to Figure 1, terminals are connected via PC5. Relay terminal 1, acting as a U2N relay terminal, connects to the next-generation node B (gNB) via the Uu interface and provides U2N relay services to downstream relay terminals / remote terminals. Remote terminals, acting as U2N remote terminals, establish Protocol Data Unit (PDU) sessions / Data Radio Bearer (DRB) sessions with the network. Data transmission between the remote terminal and the gNB is forwarded via multi-hop relay terminals. The first relay terminal (e.g., relay terminal 3) and the second relay terminal (e.g., relay terminal 4) are referred to as intermediate relay terminals (relay terminals other than the last relay terminal).

[0045] Extending from single-hop U2N trunking to multi-hop U2N trunking requires enhancements to trunk discovery and selection / reselection mechanisms; adaptation layer protocols and control plane procedures also need improvement to support multi-hop U2N trunking transmission. Based on Quality of Service (QoS) requirements, QoS in multi-hop U2N becomes particularly important to meet latency requirements despite the increased latency introduced by trunks. Therefore, how to achieve data transmission between remote terminals and access network devices in multi-hop U2N scenarios is a pressing issue that needs to be addressed.

[0046] Based on this, embodiments of this disclosure provide a communication method, apparatus, storage medium, and program product. A first relay terminal sends the identity identifier of a remote terminal to an access network device, enabling the access network device to know that the remote terminal intends to access the access network device based on the remote terminal's identity identifier, thus allowing the access network device to identify the remote terminal. Data transmitted between the remote terminal and the access network device is forwarded through the first relay terminal, and the data sent by the access network device to the remote terminal includes the remote terminal's local identifier. Thus, after receiving the remote terminal's local identifier, the first relay terminal can identify data destined for the remote terminal based on the remote terminal's local identifier, and then forward the data belonging to the remote terminal to the remote terminal. This achieves data transmission between the remote terminal and the access network device in a multi-hop U2N scenario, improving the accuracy of data transmission between the remote terminal and the access network device in such scenarios.

[0047] For example, after receiving data containing the local identifier of a remote terminal sent by the access network, the first relay terminal can identify that the data is destined for the remote terminal based on the local identifier of the remote terminal in the data. In this way, it can accurately forward the data to the remote terminal, thereby realizing data transmission between the remote terminal and the access network equipment (such as the base station) in the multi-hop U2N scenario and improving the accuracy of data transmission between the remote terminal and the access network equipment in the multi-hop U2N scenario.

[0048] The embodiments of this disclosure will now be described in conjunction with the accompanying drawings.

[0049] The technical solutions provided in this disclosure can be applied to various mobile communication networks, such as new radio (NR) mobile communication networks using 5th generation mobile networks (5G), future mobile communication networks (such as 6G wireless communication systems), or multiple communication convergence systems, etc. This disclosure does not limit these applications.

[0050] Figure 2 shows a structural diagram of a communication system provided according to an embodiment of the present disclosure. As shown in Figure 2, the communication system includes, but is not limited to, multiple terminals (e.g., remote terminal 11, relay terminal 12, relay terminal 13, and relay terminal 14) and an access network device 20. Here, the multiple terminals and the access network device 20 can transmit and receive wireless signals and perform related interactions.

[0051] In some embodiments, the access network device 20 includes a base station, which can be any of the following: an evolved NodeB (eNB), a next-generation NodeB (gNB), a transmission receive point (TRP), a transmission point (TP), a relay node, a smart metasurface (RIS), or some other access node. Based on the size of the service coverage area provided, base stations can be further classified as macro base stations for providing macrocells, micro base stations for providing microcells, and femto base stations for providing femtocells. With the continuous evolution of wireless communication technology, future base stations may also adopt other names.

[0052] In some embodiments, the terminal described above can be a device with wireless transceiver capabilities, such as a mobile phone, tablet computer, wearable device, in-vehicle device, augmented reality (AR) / virtual reality (VR) device, laptop computer, ultra-mobile personal computer (UMPC), netbook, personal digital assistant (PDA), Internet of Things (IoT) terminal, etc. This disclosure does not limit the specific type of terminal.

[0053] As shown in Figure 2, multiple terminals can be connected via PC5 port, and terminals can be connected to access network device 20 via Uu port. Based on the above description, remote terminal 11 can be referred to as a remote UE or remote node, and relay terminals 12, 13, and 14 can be referred to as relay UEs or relay nodes.

[0054] On the one hand, when the remote terminal 11 is not within the coverage area of ​​the access network device 20, the remote terminal 11 communicates with the access network device 20 through a relay path composed of relay terminal 12, relay terminal 13 and relay terminal 14. The connection between the remote terminal 11 and the relay terminal 12 is the first hop, the connection between the relay terminal 12 and the relay terminal 13 is the second hop, and the connection between the relay terminal 13 and the relay terminal 14 is the last hop.

[0055] On the other hand, after the remote terminal 11 moves to the coverage area of ​​the access network device 20, the remote terminal 11 can also switch to a direct connection path through the Uu port to communicate with the access network device 20.

[0056] Figure 2 is an exemplary structural diagram. The number of devices included in the communication system shown in Figure 2 is not limited; for example, the number of terminals and access network devices 20 is not limited. Furthermore, in addition to the devices shown in Figure 2, the communication system shown in Figure 2 may also include other devices, which are not limited thereto.

[0057] Next, as shown in Figure 3, this embodiment of the present disclosure provides a communication method. This method is applied to a first relay terminal, for example, the first relay terminal can be the relay terminal 14 shown in Figure 2 above. The method includes the following steps:

[0058] S101. Obtain the identity identifier of the remote terminal.

[0059] Here, the remote terminal communicates with the access network device through at least one relay terminal. The at least one relay terminal includes a first relay terminal. The first relay terminal is the last relay terminal in the relay path of the remote terminal. Referring to the communication system shown in Figure 2, the remote terminal can be remote terminal 11 in Figure 2, and the access network device can be access network device 20 in Figure 2.

[0060] In some embodiments, the first relay terminal is a relay terminal located within the coverage area of ​​the access network device among at least one relay terminal, or the first relay terminal is a relay terminal that has been connected to the access network device via the Uu port among at least one relay terminal.

[0061] The identity identifier of a remote terminal is used to uniquely identify the remote terminal. The identity identifier of a remote terminal may also have other names, such as user identifier, device identifier, communication identifier, identity card, unique identifier, terminal identity, host identifier, etc. This disclosure does not limit this.

[0062] In some embodiments, the identity identifier of a remote terminal includes at least one of the following:

[0063] Layer (L)2 identifier;

[0064] User information identifier;

[0065] Temporary mobile station identifier (TMSI);

[0066] Random number.

[0067] Here, TMSI includes 5G-S-TMSI, where S stands for System Architecture Evolution (SAE). 5G-S-TMSI is provided by the 5G core network and is a temporary user identifier used to uniquely identify terminals within the tracking area.

[0068] The first relay terminal can obtain the identity of the remote terminal in the following ways:

[0069] Method A1: Receive the first data packet from the remote terminal, and obtain the identity identifier of the remote terminal based on the first data packet.

[0070] Here, the first data packet is used to carry the second information, which is used to request the establishment of a connection with the access network device.

[0071] In some embodiments, the second information includes a radio resource control (RRC) connection establishment request message. The RRC connection establishment request message may also have other names, such as a signaling radio bearer (SRB) message. The random number in the remote terminal's identity identifier can be the random number included in the RRC connection establishment request message.

[0072] Assume a remote terminal selects a relay path reachable from an access network device through a multi-hop relay discovery process, and PC5 unicast links have been established between the remote terminal and each relay terminal on this relay path. Subsequently, the remote terminal can initiate an RRC connection establishment process with the access network device. In one scenario, the last relay terminal in the relay path is already connected to the access network device, while the first and intermediate relay terminals are in an RRC idle / inactive state or have no coverage, providing multi-hop relay service to the remote terminal. The remote terminal initiates an RRC connection establishment request message (SRB0 message), which needs to be forwarded to the access network device through the multi-hop relay terminals.

[0073] In some embodiments, the remote terminal generates second information, encapsulates the second information to obtain a first data packet, and then sends the first data packet to the access network device through a relay path. Correspondingly, the first relay terminal receives the first data packet sent by the remote terminal.

[0074] In some embodiments, the second information includes the identity identifier of the remote terminal. Obtaining the identity identifier of the remote terminal based on the first data packet can be done based on the second information. For example, after receiving the first data packet, the first relay terminal decapsulates the first data packet to obtain the second information, and then identifies the identity identifier of the remote terminal included in the second information.

[0075] In some embodiments, the second information may also include the DRB identifier of the remote terminal.

[0076] In some embodiments, the identity identifier of the remote terminal includes a first identity identifier and a second identity identifier. The first identity identifier is an identifier defined in the RRC connection establishment request message. For example, the first identity identifier includes at least one of the following: a temporary mobile user identifier and a random number. The second identity identifier is an identifier not defined in the RRC connection establishment request message, which can be understood as an identifier newly added in the RRC connection establishment request message. For example, the second identity identifier includes at least one of the following: an L2 identifier and a user information identifier.

[0077] In other words, if the second information includes a first identity identifier, the first relay terminal can use the first identity identifier in the second information as the identity identifier of the remote terminal. Alternatively, if the second information includes a second identity identifier, the first relay terminal can use the second identity identifier in the second information as the identity identifier of the remote terminal. Or, if the second information includes both a first identity identifier and a second identity identifier, the first relay terminal can use both the first identity identifier and / or the second identity identifier in the second information as the identity identifier of the remote terminal.

[0078] Taking the second information including the first identity identifier of the remote terminal as an example, after the remote terminal generates the second information, it encapsulates the second information into a first data packet and sends it to the first relay terminal in the relay path of the remote terminal through a predefined PC5 relay radio link control (RLC) channel. Then, the first relay terminal sends the first data packet to the first relay terminal through an intermediate relay terminal. After receiving the first data packet, the first relay terminal decapsulates the first data packet to obtain the second information, and then identifies the second information to obtain the first identity identifier of the remote terminal, and then uses the first identity identifier as the identity identifier of the remote terminal. Combining the communication system shown in Figure 2 above, the first relay terminal can be relay terminal 12 in Figure 2.

[0079] The remote terminal sends the second information to the access network device. The second information needs to be forwarded to the access network device through multiple relay terminals in the relay path. Since the first relay terminal / intermediate relay terminal is in a non-RRC connected state (e.g., RRC inactive state or RRC idle state), it cannot be controlled by the access network device. Therefore, each hop relay terminal can use the predefined PC5 relay RLC channel to forward the second information, that is, forward the first data packet.

[0080] Taking the second information including the second identity identifier of the remote terminal as an example, after the remote terminal generates the second information, it adds the second identity identifier to the second information, encapsulates the second information with the added second identity identifier into a first data packet, and sends it to the first relay terminal in the relay path of the remote terminal through a predefined PC5 relay RLC channel. Then, the first relay terminal sends the first data packet to the first relay terminal through an intermediate relay terminal. After receiving the first data packet, the first relay terminal decapsulates the first data packet to obtain the second information, and then identifies the second information to obtain the second identity identifier of the remote terminal, and then uses the second identity identifier as the identity identifier of the remote terminal.

[0081] In some embodiments of this disclosure, data transmission between terminals can be carried out through a predefined PC5 relay RLC channel, which will not be elaborated further below.

[0082] In some embodiments, the first data packet includes a second header, which contains the identity identifier of the remote terminal. Obtaining the identity identifier of the remote terminal based on the first data packet can be done by obtaining the identity identifier of the remote terminal based on the second header. For example, after receiving the first data packet, the first relay terminal identifies the remote terminal by recognizing the second header.

[0083] In some embodiments, the second header also includes the DRB identifier of the remote terminal.

[0084] In some embodiments, the second header is added to the remote terminal, or to the first relay terminal in the relay path of the remote terminal.

[0085] In some embodiments, the second header is a sidelink relay adaptation protocol (SRAP) header.

[0086] Taking the addition of a second header to a remote terminal as an example, after the remote terminal generates second information and encapsulates it into the original first data packet, it submits it to the SRAP sublayer. The SRAP sublayer of the remote terminal further adds a second header to the original first data packet, resulting in the first data packet. Then, it is sent to the first relay terminal in the relay path of the remote terminal through a predefined PC5 relay RLC channel. The first relay terminal then sends the first data packet to the first relay terminal through an intermediate relay terminal. After receiving the first data packet, the first relay terminal decapsulates it to obtain the second header, and then identifies the remote terminal's identity by recognizing the second header.

[0087] Taking the addition of a second header to the first relay terminal as an example, after the remote terminal generates second information and encapsulates it into the original first data packet, it sends the original first data packet to the first relay terminal through the predefined PC5 relay RLC channel. Upon receiving the original first data packet, the first relay terminal adds a second header to it, obtaining the first data packet. Then, the first relay terminal sends the first data packet to itself through an intermediate relay terminal. Upon receiving the first data packet, the first relay terminal decapsulates it to obtain the second header, and then identifies the second header to obtain the remote terminal's identity.

[0088] In some embodiments, the conditional second header for the original first data packet can be understood as assembling the original first data packet and the second header into an SRAP data protocol data unit (PDU).

[0089] Method A2: Receive the first information sent by the second relay terminal, and obtain the identity identifier of the remote terminal based on the first information.

[0090] Here, the first information includes the identity identifier of the remote terminal. The second relay terminal is the next-level relay terminal in the relay path of the first relay terminal in the remote terminal. Referring to the communication system shown in Figure 2 above, the second relay terminal can be relay terminal 13 in Figure 2.

[0091] Taking the second information or the first message header including the first identity identifier and the second identity identifier as an example, after the remote terminal generates the first data packet, it sends the first data packet to the first relay terminal in the relay path of the remote terminal through the predefined PC5 relay RLC channel. After receiving the first data packet, the first relay terminal identifies the second information or the first message header to obtain the first identity identifier and the second identity identifier, and then generates the first information. The first information includes the association between the first identity identifier and the second identity identifier. Then, it sends the first information to the first relay terminal through the intermediate relay terminal. After receiving the first information, the first relay terminal identifies the first information to obtain the first identity identifier and the second identity identifier of the remote terminal, and then uses the first identity identifier and / or the second identity identifier as the identity identifier of the remote terminal.

[0092] Taking the second information or the first message header including the first identity identifier or the second identity identifier as an example, after the remote terminal generates the first data packet, it sends the first data packet to the first relay terminal in the relay path of the remote terminal through the predefined PC5 relay RLC channel. After receiving the first data packet, the first relay terminal identifies the second information or the first message header to obtain the first identity identifier or the second identity identifier, and then generates the first information, which includes the first identity identifier or the second identity identifier. Then, it sends the first information to the first relay terminal through the intermediate relay terminal. After receiving the first information, the first relay terminal identifies the first information to obtain the first identity identifier or the second identity identifier of the remote terminal, and then uses the first identity identifier or the second identity identifier as the identity identifier of the remote terminal.

[0093] In some embodiments, when there are few relay terminal devices in the relay path of the remote terminal, such as when the relay path of the remote terminal only includes the remote terminal and the first relay terminal, the remote terminal is the second relay terminal. Receiving the first information sent by the second relay terminal can be receiving the first information sent by the remote terminal. The first information includes the identity identifier of the remote terminal, or the first information can include the identity identifier of the second relay terminal. Subsequently, sending the identity identifier of the remote terminal to the access network device can be sending the identity identifier of the second relay terminal to the access network device.

[0094] S102. Send the remote terminal's identity identifier to the access network equipment.

[0095] In some embodiments, in order for the access network device to know that a remote terminal has requested access to the access network device for data transmission, the access network device sends the remote terminal's identity identifier to the access network device after obtaining the remote terminal's identity identifier.

[0096] In some embodiments, the first relay terminal sends the remote terminal's identity identifier to the access network device through a predefined / default UU relay RLC channel.

[0097] In some embodiments, after the first relay terminal sends the identity identifier of the remote terminal to the access network device, it sends indication information to the access network device to indicate that the remote terminal is a multi-hop remote terminal.

[0098] S103, Receive the local identifier of the remote terminal sent by the access network device.

[0099] In some embodiments, after receiving the identity identifier of a remote terminal, the access network device determines that the remote terminal wants to access the access network device. The access network device assigns a local identifier to the remote terminal and then sends the local identifier of the remote terminal to the first relay terminal so that the first relay terminal can know the local identifier of the remote terminal for subsequent forwarding / identification of downlink data belonging to the remote terminal. Accordingly, the first relay terminal receives the local identifier of the remote terminal sent by the access network device.

[0100] The local identifier of a remote terminal refers to the identifier or name used to uniquely identify the remote terminal in the local area or on the network.

[0101] The local identifier of a remote terminal includes at least one of the following: hardware address (such as media access control (MAC) address), internet protocol (IP) address, username, device name, or any other string that can uniquely identify the remote terminal.

[0102] The local identifier may also have other names, such as device identifier, device identifier, node identifier, node name, hostname, username, etc., and this disclosure does not limit this.

[0103] Using a remote terminal's local identifier serves several purposes. First, it ensures the remote terminal has a unique identity within the network or system, facilitating management and tracking. Second, in network communication, the local identifier determines the data transmission and reception paths, ensuring correct data delivery to the remote terminal. Third, a local identifier is shorter than a traditional identifier, saving overhead. For example, in a relay scenario with multiple remote terminals, the local identifier of each remote terminal only needs to be unique within that relay scenario. This allows the relay terminal and access network equipment to identify the remote terminal's data, and subsequent data transmissions between the remote terminal and access network equipment will carry a data packet header containing the remote terminal's local identifier.

[0104] In this embodiment, the first relay terminal sends the remote terminal's identity identifier to the access network device, enabling the access network device to recognize the remote terminal's intention to connect based on the identifier, thus allowing the access network device to identify the remote terminal. Data transmitted between the remote terminal and the access network device is forwarded through the first relay terminal, and the data sent by the access network device to the remote terminal includes the remote terminal's local identifier. Thus, after receiving the remote terminal's local identifier, the first relay terminal can identify data destined for the remote terminal based on this identifier, and accurately forward the data to the remote terminal. This achieves data transmission between the remote terminal and the access network device in a multi-hop U2N scenario, improving the accuracy of data transmission in such scenarios.

[0105] The above embodiment illustrates how a first relay terminal, after obtaining the identity identifier of a remote terminal, sends the remote terminal's identity identifier to an access network device to obtain the remote terminal's local identifier. In some embodiments, after receiving a first data packet containing the remote terminal's identity identifier (e.g., second information includes the remote terminal's identity identifier or a first header includes the remote terminal's identity identifier) ​​sent by the remote terminal, any relay terminal in the remote terminal's relay path does not process the first data packet but forwards it to the next higher-level relay terminal, indicating that the first data packet is forwarded to the access network device. After receiving the first data packet, the access network device identifies the first data packet, obtains the remote terminal's identity identifier, assigns a local identifier to the remote terminal, and then sends the remote terminal's local identifier to the first relay terminal. Accordingly, the first relay terminal receives the remote terminal's local identifier sent by the access network device.

[0106] In some embodiments, after receiving a first data packet containing second information from a remote terminal, the first relay terminal may send the second information to the access network device in order to establish a communication connection between the remote terminal and the access network device. The first relay terminal may send the second information to the access network device in the following ways.

[0107] Method B1: Send the first data packet to the access network device.

[0108] In other words, the first relay device does not process the first data packet but directly sends it to the access network device. Correspondingly, the access network device receives the first data packet sent by the first relay device.

[0109] Method B2: Send a second data packet to the access network device.

[0110] Here, the second data packet is used to carry the second information. The second data packet has a first header added to it, and the first header includes the local identifier of the remote terminal.

[0111] In other words, after receiving the first data packet, the first relay device adds the first header to the first data packet without adding the second header, thus obtaining the second data packet, and then sends the second data packet.

[0112] Alternatively, if the first data packet has a second header, the second header can be removed and the first header added to obtain the second data packet, which can then be sent.

[0113] In some embodiments, after the first relay device sends a first data packet or a second data packet to the access network device, that is, after sending second information to the access network device, it receives a third data packet from the access network device. The third data packet is used to carry third information, which relates to establishing a connection with a remote terminal.

[0114] In some embodiments, the third information includes an RRC setup message.

[0115] After receiving a third data packet containing third information, the first relay device can send the third information to a remote terminal through an intermediate relay terminal. For example, this may include the following scenarios:

[0116] Scenario 1: The third data packet is appended with a first header, which includes the local identifier of the remote terminal.

[0117] In scenario 1, in order for the second relay terminal to identify the remote terminal based on the local identifier of the remote terminal in the first packet header, and to enable the second relay terminal to further route / forward data, the first relay device sends a third data packet and fourth information to the second relay terminal. Here, the fourth information includes the identity identifier of the remote terminal and the local identifier of the remote terminal.

[0118] Thus, the second relay terminal can determine that the third data packet is destined for the remote terminal based on the identity identifier of the remote terminal and the local identifier of the remote terminal included in the fourth information, and then the second relay terminal forwards the third data packet and the fourth information to the next level relay terminal of the second relay terminal.

[0119] In some embodiments, in order for each relay terminal to correctly route signaling belonging to a remote terminal to the next-level relay terminal during downlink data forwarding, each relay terminal records which sub-node each remote terminal received second information from. Based on this recorded information, each relay terminal can obtain and save a downlink routing map, which, for example, contains the identity of the remote terminal and the identifier of the next-hop relay terminal.

[0120] Based on this, the first relay terminal sending the third data packet and the fourth information to the second relay terminal can be achieved by the first relay terminal determining the second relay terminal based on the downlink routing table, and then sending the third data packet and the fourth information to the second relay terminal. This method of the first relay terminal determining the second relay terminal based on the downlink routing table and then sending the third data packet and the fourth information to the second relay terminal is merely illustrative; this example also applies to scenarios 2 to 4 below, and will not be elaborated further.

[0121] In some embodiments, the fourth information includes a PC5 RRC message.

[0122] In some embodiments, the first header may also include the DRB identifier of the remote terminal.

[0123] Scenario 2: The third data packet is appended with a first header, which includes the local identifier of the remote terminal.

[0124] In scenario 2, in order for the second relay terminal to identify the remote terminal and to further route / forward data, the first relay terminal sends a fourth data packet to the second relay terminal. Here, the fourth data packet carries the third information and includes a second header containing the remote terminal's identifier.

[0125] In other words, when the first relay terminal receives a third data packet with a first header, it removes the first header, adds a second header, and obtains a fourth data packet, which it then sends to the second relay terminal. Upon receiving the fourth data packet, the second relay terminal can determine that the fourth data packet is destined for a remote terminal based on the remote terminal identifier in the second header. It then determines the next-level relay terminal based on the downlink routing table and forwards the fourth data packet to that next-level relay terminal.

[0126] In the relay path of the remote terminal, each relay terminal stores the identity identifier of the remote terminal. If the first relay terminal directly forwards the third data packet to the second relay terminal, the third data packet only includes the local identifier of the remote terminal. The second relay terminal cannot determine that the third data packet is sent to the remote terminal. Therefore, in case 2, the first relay terminal changes the header of the third data packet to obtain the fourth data packet, and then sends the fourth data packet to the second relay terminal. This enables the second relay terminal to identify the remote terminal and to continue routing / forwarding data.

[0127] In some embodiments, the second header also includes the DRB identifier of the remote terminal.

[0128] Scenario 3: The third data packet is accompanied by a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal.

[0129] In scenario 3, the first relay terminal sends a third data packet to the second relay terminal.

[0130] If the third header includes the local identifier and the remote terminal's identity identifier, the second relay terminal can determine that the third data packet is destined for the remote terminal based on its own stored remote terminal identity identifier and the remote terminal's identity identifier in the third header. Therefore, in scenario 3, the first relay terminal can directly send the third data packet to the second relay terminal. The second relay terminal then continues to forward the third data packet to the next lower-level relay terminal.

[0131] In some embodiments, the third header may also include the DRB identifier of the remote terminal.

[0132] Scenario 4: The third piece of information includes the identity identifier of the remote terminal.

[0133] In scenario 4, the first relay terminal sends a third data packet to the second relay terminal.

[0134] If the third header includes the local identifier and the remote terminal's identity identifier, the second relay terminal can determine that the third data packet is destined for the remote terminal based on its own stored remote terminal identity identifier and the remote terminal's identity identifier in the third header. Therefore, in scenario 3, the first relay terminal can directly send the third data packet to the second relay terminal. The second relay terminal then continues to forward the third data packet to the next lower-level relay terminal until the remote terminal receives it.

[0135] The above embodiments illustrate how to achieve data transmission between remote terminals and access network devices in multi-hop U2N scenarios. In some embodiments, in single-hop L2 U2N relay scenarios, the access network device needs to guarantee the QoS of the remote terminal. For example, the access network device configures the corresponding Uu relay RLC channel and PC5 relay RLC channel according to the Uu QoS of the remote terminal. In addition, to support mode 2 resource selection, a programmable delay block (PDB) is associated with the configuration of the PC5 relay RLC channel. Similarly, in multi-hop relay scenarios, the access network device can divide the Uu QoS of the remote terminal's DRB into the Uu QoS between the last relay terminal and the access network device and configure appropriate Uu relay RLC channels and the remaining QoS (multiple hops between the remote terminal and the last terminal). How to guarantee the QoS of multiple hops between the remote terminal and the last terminal in multi-hop U2N scenarios, that is, how to guarantee the QoS of each link in the relay path of the remote terminal in multi-hop U2N scenarios, becomes an urgent problem to be solved.

[0136] Based on this, the method may also include the following steps:

[0137] X1, Receive the sixth message.

[0138] Here, the sixth piece of information is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path, that is, to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal. A link can be understood as a hop, that is, the configuration of the PC5 relay RLC channel of the hop between the remote terminal and the first relay terminal.

[0139] In some embodiments, the configuration of the PC5 trunk RLC channel of the link between the remote terminal and the first trunk terminal in the trunk path can be used for other links in the trunk path. That is, the configuration of the PC5 trunk RLC channel of different links in the trunk path can be the same.

[0140] In some embodiments, the sixth information is also used to indicate the configuration of the PC5 relay RLC channel of other links in the relay path, wherein the configuration of the PC5 relay RLC channel of at least one of the other links is different from the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path. That is, the configuration of the PC5 relay RLC channel of different links in the relay path can be different.

[0141] In some embodiments, the sixth information further includes the DRB identifier associated with each link in the relay path of the remote terminal. In some embodiments, the sixth information further includes the DRB identifier associated with the link between the relay terminal and the first relay terminal.

[0142] Thus, after receiving the sixth information, a relay terminal can associate the configuration of the PC5 relay RLC channel of the link corresponding to the relay terminal with the corresponding DRB identifier.

[0143] Taking the link between the remote terminal and the first relay terminal as the first link as an example, the sixth information is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path. This can be understood as the sixth information indicating the configuration of the PC5 relay RLC channel of the DRB associated with the first link. The configuration of the PC5 relay RLC channel for different DRBs of the remote terminal can be the same or different. When the configuration of the PC5 relay RLC channel for different DRBs of the remote terminal is different, it can be understood that the different DRBs of the remote terminal are transmitted through different PC5 relay RLC channels.

[0144] In some embodiments, the sixth information described above, which is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal, can be replaced by the sixth information being used to indicate the configuration of the PC5 relay RLC channel of the link between the first relay terminal and the second relay terminal in the relay path of the remote terminal.

[0145] The configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path can be used for other links in the relay path, and can be replaced by the configuration of the PC5 relay RLC channel of the link between the first relay terminal and the second relay terminal, which can be used for other links in the relay path.

[0146] The configuration of the PC5 relay RLC channel in at least one of the other links is different from the configuration of the PC5 relay RLC channel in the link between the remote terminal and the first relay terminal in the relay path. It can be replaced by the configuration of the PC5 relay RLC channel in at least one of the other links being different from the configuration of the PC5 relay RLC channel in the link between the first relay terminal and the second relay terminal.

[0147] In some embodiments, the sixth information also includes the DRB identifier of the remote terminal. Thus, a relay terminal in the relay path of the remote terminal can determine the configuration of the PC5 relay RLC channel indicated by the sixth information and associate it with the remote terminal based on the DRB identifier of the remote terminal.

[0148] In some embodiments, after determining the configuration of the PC5 relay RLC channel of the link between the first relay terminal and the second relay terminal based on the sixth information, the first relay terminal establishes a receiving entity corresponding to the PC5 relay RLC channel between itself and the second relay terminal.

[0149] In some embodiments, receiving the sixth information may be receiving the sixth information from a remote terminal (i.e., receiving the sixth information sent by the second relay terminal) or receiving the sixth information from an access network device.

[0150] Receiving the sixth information from the remote terminal can be achieved by the remote terminal receiving the sixth information forwarded by the access network device through a relay terminal in the relay path, and then sending the sixth information to the first relay terminal through the relay path. Correspondingly, the first relay terminal receives the sixth information from the remote terminal.

[0151] Information sent from access network devices to remote terminals via relay terminals in the relay path is generally encrypted. The relay terminals in the relay path only forward the information without decryption. Therefore, after receiving the encrypted sixth message, the remote terminal can decrypt it and then send the decrypted sixth message to the first relay terminal via the relay terminals in the relay path. Each relay terminal in the relay path, upon receiving the sixth message, obtains the PC5 relay RLC channel configuration for its corresponding link based on the sixth message and sends the sixth message to the next higher-level relay terminal until the first relay terminal receives it.

[0152] The first relay terminal receives the sixth information from the access network equipment. This can be achieved by receiving the encrypted sixth information, decrypting it, and then sending the decrypted sixth information to the remote terminal. Each relay terminal in the relay path, upon receiving the sixth information, obtains the PC5 relay RLC channel configuration for its corresponding link based on the sixth information and sends the sixth information to the next-level relay terminal, until the remote terminal receives the sixth information.

[0153] The above embodiments illustrate how the access network device directly instructs each relay terminal in the relay path of the remote terminal to send the configuration of the PC5 relay RLC channel of the link corresponding to each relay terminal. In some embodiments, the access network device may also indirectly instruct each relay terminal in the relay path of the remote terminal to send the configuration of the PC5 relay RLC channel of the link corresponding to each relay terminal.

[0154] Based on this, the method may also include the following steps:

[0155] Q1. Receive the seventh message from the second relay terminal.

[0156] The seventh piece of information is used to indicate the PC5 service quality configuration between the second relay terminal and the first relay terminal.

[0157] In some embodiments, the seventh information also includes the association (mapping) between the DRB identifier of the remote terminal and the PC5 service quality configuration between the second relay terminal and the first relay terminal.

[0158] After receiving the seventh information, the first relay terminal can determine the configuration of the PC5 relay RLC channel between the first relay terminal and the second relay terminal based on its own coverage status, the configuration in the system information block (SIB) / pre-configuration, and the PC5 service quality configuration between the second relay terminal and the first relay terminal. It then associates the configuration of the PC5 relay RLC channel between the first relay terminal and the second relay terminal with the DRB identifier of the remote terminal.

[0159] In some embodiments, in order to assist the access network device in configuring the PC5 trunk RLC channel, the first trunk terminal sends fifth information to the access network device. The fifth information is used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first trunk terminal.

[0160] In this way, each relay terminal in the relay path determines the configuration of the PC5 relay RLC channel of the link corresponding to each relay terminal based on the sixth or seventh information, thus ensuring the QoS of each link in the relay path of the remote terminal in the multi-hop U2N scenario.

[0161] The above embodiments illustrate a communication method provided by this disclosure from the perspective of a first relay terminal. In some embodiments, as shown in FIG4, this disclosure also provides a communication method applied to a remote terminal, which may include the following steps:

[0162] S201. Send the second information to the access network equipment through the first relay terminal.

[0163] Here, the relay path of the remote terminal includes at least one relay terminal, the first relay terminal is one of the at least one relay terminal, and the second information is used to request the establishment of a connection with the access network device. For the description of the second information and the first relay terminal, please refer to the corresponding description in the embodiment shown in Figure 3 above, and it will not be repeated here.

[0164] In some embodiments, when a remote terminal determines a relay path that can reach an access network device through a multi-hop relay discovery process, and a PC5 unicast link has been established between each relay terminal on the relay path, the remote terminal sends the second information to the access network device through the relay terminals in the relay path.

[0165] In some embodiments, the remote terminal sends a first data packet to the access network device, the first data packet being used to carry second information.

[0166] In some embodiments, the second information includes the identity identifier of the remote terminal.

[0167] The identity of a remote terminal includes at least one of the following:

[0168] L2 sign;

[0169] User information identifier;

[0170] Temporary mobile user identifier;

[0171] Random number.

[0172] For a description of the identity of the remote terminal, please refer to the corresponding description in the embodiment shown in Figure 3 above, which will not be repeated here.

[0173] In some embodiments, the first data packet is appended with a second header, which includes the identity identifier of the remote terminal. For a description of the second header, please refer to the corresponding description in the embodiment shown in Figure 3 above, and it will not be repeated here.

[0174] S202, Receive third information from the access network device.

[0175] Here, the third piece of information is used to establish a connection with the remote terminal.

[0176] In some embodiments, the third information includes an RRC establishment message. For a description of the third information, please refer to the description of the third information in the above embodiments, and it will not be repeated here.

[0177] In some embodiments, a third data packet is received from an access network device, the third data packet being used to carry third information.

[0178] In some embodiments, the third data packet is appended with a first header, which includes a local identifier of the remote terminal.

[0179] In some embodiments, the third data packet is supplemented with a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal.

[0180] In some embodiments, the third information includes the identity identifier of the remote terminal.

[0181] For a description of receiving a third data packet from an access network device, please refer to the descriptions of Situations 1 to 4 above, which will not be repeated here.

[0182] In some embodiments, a fourth data packet is received from the first relay terminal. This fourth data packet carries third information. The description of the fourth data packet can be found in the corresponding description in scenario 2 above, and will not be repeated here.

[0183] In some embodiments, in order to guarantee the QoS of each link in the relay path of a remote terminal in a multi-hop U2N scenario, the method may further include the following steps:

[0184] W1, Receive the sixth message from the access network device.

[0185] Here, the sixth piece of information is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

[0186] In some embodiments, the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path can be used for other links in the relay path.

[0187] In some embodiments, the sixth information is also used to indicate the configuration of the PC5 relay RLC channel of other links in the relay path, wherein the configuration of the PC5 relay RLC channel of at least one link in the other links is different from the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path.

[0188] In some embodiments, the sixth information also includes a DRB identifier associated with the link between the relay terminal and the first relay terminal.

[0189] The description of the sixth piece of information can be found in the corresponding description of the sixth piece of information in step X1 above, and will not be repeated here.

[0190] W2, send the sixth message to the first relay terminal.

[0191] After receiving the sixth information, the first relay terminal establishes the receiver entity corresponding to the PC5 relay RLC channel with the remote terminal, and further initiates the PC5 relay RLC channel establishment process with the first relay terminal's upstream relay terminal. Then, the upstream relay terminal of the first relay terminal continues to transmit the sixth information to the upstream relay terminal of that upstream relay terminal until the sixth information is transmitted to the first relay terminal.

[0192] The above embodiments illustrate the example of the access network device directly instructing the configuration of the PC5 trunk RLC channel of each link in the trunk path. In some embodiments, the access network device can indirectly instruct the configuration of the PC5 trunk RLC channel of each link in the trunk path. The method may also include the following steps:

[0193] R1 receives the eighth message from the access network device.

[0194] Here, the eighth piece of information is used to indicate the PC5 service quality configuration of each link in the relay path of the remote terminal.

[0195] R2, send the ninth message to the first relay terminal in the relay path.

[0196] Here, the ninth information is used to indicate the PC5 quality of service configuration for links in the relay path other than the link between the remote terminal and the first relay terminal.

[0197] After receiving the ninth message, the first relay terminal sends the eleventh message to the next-level relay terminal. The eleventh message is used to indicate the PC5 service quality configuration of the links in the relay path other than the link between the first relay terminal and the next-level relay terminal.

[0198] In other words, after receiving information including the PC5 service quality configuration of multiple links, a relay terminal saves the PC5 service quality configuration of its own corresponding link, divides the PC5 service quality configuration of multiple links, deletes the PC5 service quality configuration of its own corresponding link from the information, and then sends the PC5 service quality configuration of the remaining links to the next higher-level relay terminal, until the first relay terminal receives the seventh information sent by the second relay terminal.

[0199] The effect of step R2 can be referred to the corresponding description in step Q1 above, and will not be repeated here.

[0200] In some embodiments, in order to assist the access network device in configuring the PC5 relay RLC channel, the remote terminal sends fifth information to the access network device. The fifth information is used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first relay terminal.

[0201] In some embodiments, in order to assist the access network device in configuring the PC5 relay RLC channel, the remote terminal sends tenth information to the access network device. The tenth information is used to indicate the PC5 link quality of each link in the relay path of the remote terminal.

[0202] The above embodiments describe a communication method provided by the present disclosure from the perspective of a first relay terminal or a remote terminal. In some embodiments, as shown in FIG5, the present disclosure also provides a communication method applied to an access network device, which may include the following steps:

[0203] S301, Receive the identity identifier of the remote terminal sent by the first relay terminal.

[0204] Here, the remote terminal communicates with the access network equipment through the first relay terminal.

[0205] In some embodiments, the identity identifier of a remote terminal includes at least one of the following:

[0206] L2 sign;

[0207] User information identifier;

[0208] Temporary mobile user identifier;

[0209] Random number.

[0210] For a description of the identity of the remote terminal, please refer to the corresponding description in the embodiment shown in Figure 3 above, which will not be repeated here.

[0211] S302, Send the local identifier of the remote terminal to the first relay terminal.

[0212] In some embodiments, after receiving the identity identifier of a remote terminal, the access network device identifies the remote terminal and determines that the remote terminal wants to access the access network device. The access network device assigns a local identifier to the remote terminal and then sends the local identifier of the remote terminal to the first relay terminal so that the first relay terminal can identify the remote terminal and receive / identify downlink data belonging to the remote terminal. This enables data transmission between the remote terminal and the access network device in a multi-hop U2N scenario and improves the accuracy of data transmission between the remote terminal and the access network device in a multi-hop U2N scenario.

[0213] In some embodiments, the method may further include the following steps:

[0214] T1. Receive the second information sent by the remote terminal through the first relay terminal.

[0215] Here, the second piece of information is used to request the establishment of a connection with the access network device.

[0216] For a description of the second information, please refer to the corresponding description in the embodiment shown in Figure 3 above, which will not be repeated here.

[0217] In some embodiments, a first data packet sent by a remote terminal through a first relay terminal is received, the first data packet being used to carry second information.

[0218] In some embodiments, the second information includes the identity identifier of the remote terminal.

[0219] In some embodiments, the first data packet is appended with a second header, which includes the identity identifier of the remote terminal.

[0220] In some embodiments, a second data packet sent by a first relay terminal is received. The second data packet carries second information and has a first header added to it. The first header includes the local identifier of the remote terminal.

[0221] T2. Send third information to the remote terminal.

[0222] Here, the third information is used to establish a connection with the remote terminal. For a description of the third information, please refer to the corresponding description in the embodiment shown in Figure 3 above, which will not be repeated here.

[0223] In some embodiments, a third data packet is sent from a first relay terminal to a remote terminal, the third data packet being used to carry third information.

[0224] In some embodiments, the third data packet is appended with a first header, which includes a local identifier of the remote terminal.

[0225] In some embodiments, the third data packet is supplemented with a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal.

[0226] In some embodiments, the third information includes the identity identifier of the remote terminal.

[0227] For a description of step T2, please refer to the descriptions of cases 1 to 4 above, which will not be repeated here.

[0228] In some embodiments, to assist the access network device in configuring the PC5 trunk RLC channel and improve the accuracy of the PC5 trunk RLC channel configuration, the access network device receives fifth information. This fifth information indicates the hop count between the remote terminal and the access network device, or between the remote terminal and the first trunk terminal. Here, receiving the fifth information can be either receiving fifth information sent by the remote terminal or receiving fifth information sent by the first intermediate terminal.

[0229] After receiving the fifth information, the access network device can configure the PC5 relay RLC channel based on the fifth information.

[0230] In some embodiments, in order to assist the access network device in configuring the PC5 trunk RLC channel and improve the accuracy of configuring the PC5 trunk RLC channel, the access network device receives tenth information from the remote terminal. The tenth information is used to indicate the PC5 link quality of each link in the trunk path of the remote terminal.

[0231] After receiving the tenth information, the access network device can configure the PC5 relay RLC channel based on the tenth information.

[0232] In some embodiments, to ensure QoS of each link in the relay path of a remote terminal in a multi-hop U2N scenario, the access network device can determine the configuration of the PC5 relay RLC channel of each link in the relay path of the remote terminal, and then indicate the configuration of the PC5 relay RLC channel of each link in the relay path of the remote terminal. Based on this, the method may further include the following steps:

[0233] Y1, Send the sixth message.

[0234] The sixth piece of information is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

[0235] In some embodiments, the sixth information also includes a DRB identifier associated with the link between the relay terminal and the first relay terminal.

[0236] In some embodiments, the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path can be used for other links in the relay path.

[0237] In some embodiments, the sixth information is also used to indicate the configuration of the PC5 relay RLC channel of other links in the relay path, wherein the configuration of the PC5 relay RLC channel of at least one link in the other links is different from the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path.

[0238] Sending the sixth message can be done by sending the sixth message to a remote terminal or by sending the sixth message to the first relay terminal.

[0239] The description of step Y1 can be found in the description of step X1 above, and will not be repeated here.

[0240] The method described in step Y1 above is illustrated by taking the example of the access network device directly instructing the configuration of the PC5 relay RLC channels of each link in the relay path of the remote terminal. In some embodiments, the access network device can indirectly instruct the configuration of the PC5 relay RLC channels of each link in the relay path of the remote terminal. Based on this, the method may further include the following steps:

[0241] P1. Send the eighth message to the remote terminal.

[0242] Here, the eighth piece of information is used to indicate the PC5 service quality configuration of each link in the relay path of the remote terminal.

[0243] The description of step P1 can be found in the descriptions of steps Q1 and R2 above, and will not be repeated here.

[0244] The following examples illustrate a communication method provided in this disclosure. In these examples, Remote UE is a remote terminal, First relay UE is the first relay terminal, Intermediate relay UE is the second relay terminal, Last relay UE is the first relay terminal, and the base station is an access network device.

[0245] First, in order to achieve data transmission between remote terminals and access network devices in multi-hop U2N scenarios, the following example can be included.

[0246] Example H1.

[0247] The Remote UE sends an RRC connection establishment request message to the First relay UE via a predefined PC5 Relay RLC channel. The First relay UE adds an SRAP header to the received data packet (SRB0) (assembling it into an SRAP data PDU) and sends it to the Intermediate relay UE via the predefined PC5 Relay RLC channel. The SRAP header contains the Remote UE's identity (e.g., L2 ID) and may include an SRB identifier. Upon receiving the data packet, the Intermediate relay UE directly sends it to the Last relay UE via the predefined PC5 Relay RLC channel. Upon receiving the data packet (SRAP data PDU), the Last relay UE identifies the Remote UE's L2 ID through the SRAP header, reports the Remote UE's L2 ID to the base station, and indicates that the UE is a multi-hop Remote UE. The base station assigns a local identifier to the Remote UE and sends this local identifier to the Last relay UE. The Last relay UE removes the original SRAP header from the received Remote UE data packets and adds a new SRAP header. The header (assembled into an SRAP data PDU) contains the local identifier of the Remote UE and the SRB identifier, and the Remote UE's data packets (new SRAP data PDU) are sent to the base station through the configured Uu Relay RLC channel according to the base station's configuration.

[0248] Alternatively, after receiving the data packet, the Last relay UE directly sends the received data packet to the base station through the predefined / default Uu Relay RLC channel. Upon receiving the data packet, the base station identifies the Remote UE's L2 ID through the SRAP header, parses the Remote UE's RRC connection establishment request message, assigns a local identifier to the Remote UE, and sends the Remote UE's local identifier (along with the Remote UE's L2 ID) to the Last relay UE so that the Last relay UE knows the Remote UE's local identifier and can thus receive / identify the Remote UE's downlink data.

[0249] Example H2.

[0250] After the Remote UE generates an RRC connection establishment request, it submits it to the SRAP sublayer. The Remote UE's SRAP sublayer further adds an SRAP header to the SRB0 data packet (assembling it into an SRAP data PDU) and sends it to the First relay UE through the predefined PC5 relay RLC channel. The SRAP header contains the Remote UE's L2 ID and the SRB identifier. Subsequently, the First relay UE and the Intermediate relay UE directly forward the received data packet without any processing (or remove the original SRAP header and re-add the same SRAP header). After the Last relay UE receives the data packet (SRAP data PDU), it identifies the Remote UE's L2 ID through the SRAP header. The processing at the Last relay UE is the same as in Example H1.

[0251] Example H2 corresponds to the example in method A1 above where the second message header is added for the remote terminal.

[0252] Example H3.

[0253] The Remote UE introduces a new Remote UE identifier, such as the Remote UE's L2 ID or user InfoID, into its RRC connection establishment request message. The Remote UE sends the RRC connection establishment request message containing the L2 ID to the First relay UE (the data packet has no SRAP header) through the predefined PC5 relay RLC channel, and then forwards it to the Last relay UE via the First relay UE and the Intermediate relay UE (the intermediate relay node does not process the data packet and forwards it directly). Since the Remote UE's SRB0 is not encrypted, assuming the Last relay can identify the Remote UE's identity (L2 ID) in the RRC message, the Last relay UE reports the Remote UE's L2 ID to the base station and indicates that the UE is a multi-hop Remote UE. The base station assigns a local identifier to the Remote UE and sends the Remote UE's local identifier to the Last relay. The Last relay adds an SRAP header to the received Remote UE data packets (assembling them into SRAP data PDUs). The SRAP header contains the Remote UE's local identifier and SRB identifier, and according to the base station's configuration, sends the Remote UE's data packets (SRAP data PDUs) to the base station through the configured Uu RelayRLC channel.

[0254] Alternatively, after receiving the data packet, the Last relay UE directly sends the received data packet to the base station through the predefined / default Uu Relay RLC channel. Upon receiving the data packet, the base station parses the Remote UE's RRC connection establishment request message and identifies the Remote UE's L2 ID. It then assigns a local identifier to the Remote UE and sends the Remote UE's local identifier (along with its L2 ID) to the Last relay UE so that the Last relay UE knows the Remote UE's local identifier and can thus receive / identify the Remote UE's downlink data.

[0255] Example H4.

[0256] The remote UE sends its RRC connection establishment request message to the First relay UE via the predefined PC5 relay RLC channel (the data packet has no SRAP header); it is then forwarded by the First relay UE and the Intermediate relay UE (the intermediate relay nodes do not process the data packet and forward it directly) to the Last relay UE. The remote UE's RRC connection establishment request message contains its 5G-S-TMSI or a random number as an identifier. The Last relay UE reports the remote UE's 5G-S-TMSI or random number as an identifier to the base station. The base station assigns a local identifier to the remote UE and sends the remote UE's local identifier to the Last relay UE. Subsequent processing at the Last relay UE is the same as in Example H3.

[0257] Example H5.

[0258] The Remote UE sends an RRC connection establishment request message to the First relay UE via a predefined PC5 relay RLC channel. The Remote UE then sends its own 5G-S-TMSI or random number identifier to the First relay UE via a PC5-RRC message. Alternatively, the First relay UE identifies the Remote UE's 5G-S-TMSI or random number identifier in the RRC connection establishment request message, and then sends the association between the Remote UE's 5G-S-TMSI or random number identifier and the Remote UE's L2 ID to the Intermediate relay UE via a PC5-RRC message. That is, the PC5 RRC message contains at least one of the following: the Remote UE's 5G-S-TMSI, a random number, or an L2 ID. The Intermediate relay UE further sends this association to the Last relay UE via a PC5-RRC message, and the Last relay UE obtains the Remote UE's L2 ID. Subsequent processing at the Last relay is the same as in Example H3.

[0259] Example H5 corresponds to the example in method A1 above where the second message header is added for the first relay terminal.

[0260] Example H6.

[0261] After receiving the RRC connection establishment request message from the Intermediate relay UE, the Last relay UE reports the Intermediate relay's identity (e.g., L2 ID) to the base station and indicates that the UE is the Intermediate relay. The base station assigns a local identifier to the Intermediate relay and configures the Uu Relay RLC channel and bearer mapping for forwarding SL-RLC0. The Last relay adds an SRAP header to the Remote UE's SRB0 data packets and sends them to the base station. The SRAP header contains the Intermediate relay's local identifier and the SL RLC channel identifier. Upon receiving the message, the base station parses the Remote UE's RRC connection establishment request message, assigns a local identifier to the Remote UE, and sends the Remote UE's local identifier to the Last relay UE.

[0262] Example H6 corresponds to a scenario where the relay path for the Remote UE only includes the Remote UE and the Last relay UE, where the Remote UE is the Intermediate relay UE.

[0263] For the descriptions of examples H1 to H6, please refer to the descriptions of methods A1 and A2 above, which will not be repeated here.

[0264] After receiving the RRC connection establishment request message from the Remote UE, the base station configures the local identifier, the PC5 relay RLC channel for sending SRB1, and the bearer mapping for the Remote UE, and includes the above information in the RRC setup message and sends it to the Remote UE (via multi-hop relays). To ensure that each hop node correctly routes the Remote UE's signaling to downstream nodes during downlink, the Intermediate Relay UE / Last Relay UE needs to record which sub-node each Remote UE's RRC setup request was received from. That is, the Last Relay UE and all Intermediate Relay UEs obtain and save the downlink routing mapping table based on this record information, which includes, for example, the Remote UE's identity and the next-hop node's identifier.

[0265] When transmitting downlink data, in order for the Last relay UE and each Intermediate relay UE to recognize the Remote UE's RRC setup message, the following example may be included:

[0266] Example K1.

[0267] After the base station generates the RRC setup message for the Remote UE, it passes it down to the SRAP sublayer. The SRAP sublayer adds an SRAP header and sends it to the Last relay via the configured Uu Relay RLC channel. The SRAP header contains the Remote UE's local identifier and SRB identifier. The Last relay UE identifies the Remote UE using the local identifier in the SRAP header and identifies the next-hop node (Intermediate relay UE) based on the recorded / saved downlink routing mapping table. It then forwards the received data packets to the next-hop Intermediate relay UE via the predefined PC5 relay RLC channel. To enable the next-hop Intermediate relay UE to identify the Remote UE based on the local identifier in the data packet's SRAP header and continue routing / forwarding data downstream, the Last relay UE can send the Remote UE's identity and local identifier to the Intermediate relay UE via a PC5-RRC message. Subsequent processing at the Intermediate relay UE is the same as at the Last relay UE. For example, the Intermediate relay UE identifies the Remote UE based on the local identifier in the SRAP header of the data packet and the association between the Remote UE's identity identifier and the local identifier sent by the Last relay UE. Then, it further finds the next-hop node (First relay UE) according to the stored downlink routing mapping table, sends the data packet to the First relay UE, and sends the Remote UE's identity identifier and local identifier to the First relay UE via a PC5-RRC message. After receiving the data packet, the First relay UE identifies the Remote UE based on the SRAP header, removes the SRAP header, and then sends the data packet to the Remote UE through the predefined PC5 relay RLC channel.

[0268] Example K1 corresponds to case 1 above.

[0269] Example K2.

[0270] After the base station generates the RRC setup message for the Remote UE, it passes it down to the SRAP sublayer. The SRAP sublayer adds an SRAP header and sends it to the Last relay UE via the configured Uu Relay RLC channel. The SRAP header contains the Remote UE's Local ID and SRB identifier. The Last relay UE identifies the Remote UE using the Local ID in the SRAP header and identifies the next-hop node (Intermediate relay UE) based on the recorded / stored downlink routing mapping table. Since all Intermediate relay UEs store the Remote UE's identity, the Intermediate relay does not have the association between the Remote UE's identity and Local ID, and therefore cannot identify the Remote UE solely through the Local ID in the packet's SRAP header. To enable the Intermediate relay UE to identify the Remote UE, the Last relay UE, upon receiving the Remote UE's data packet from the base station, removes the original SRAP header and adds a new one. This new SRAP header contains the Remote UE's identity and SRB identifier. The Last relay UE sends a data packet containing the new SRAP header to the identified next-hop Intermediate relay UE. Upon receiving the packet, the Intermediate relay UE can identify the Remote UE based on the identity identifier in the SRAP header.

[0271] Example K2 corresponds to case 2 above.

[0272] Example K3.

[0273] To enable the Intermediate Relay UE to know the mapping between the Remote UE's identity and its local identifier, the base station generates an RRC setup message for the Remote UE and then submits it to the SRAP sublayer. The SRAP sublayer adds an SRAP header containing the Remote UE's local identifier and identity (as well as its SRB identifier). The base station then sends the data packet containing the SRAP header to the Last Relay UE via the configured Uu Relay RLC channel. The Last Relay UE identifies the Remote UE based on the identity and local identifier in the SRAP header, finds the next-hop Intermediate Relay UE according to the stored downlink routing table, and directly forwards the data packet received from the base station to the next-hop Intermediate Relay UE via the predefined PC5 Relay RLC channel (the Last Relay does not modify the data packet SRAP header). The Intermediate Relay UE can then identify the Remote UE based on the identity and local identifier in the data packet SRAP header.

[0274] Example K3 corresponds to case 3 above.

[0275] Example K4.

[0276] The RRC setup message includes the Remote UE's identity and local identifier. Since the RRC setup message (SRB0) is unencrypted, it can be assumed that each Intermediate relay UE, upon receiving the Remote UE's RRC setup message, can identify the Remote UE's identity and local identifier contained in the RRC setup message.

[0277] After receiving the RRC setup, the Remote UE obtains the Remote UE's local identifier, the configuration of the PC5 Relay RLC channel corresponding to SRB1, and the bearer mapping. The Remote UE adds an SRAP header to SRB1 (RRC Setup Complete), which contains the local identifier and the DRB identifier, and sends it to the Intermediate relay UE through the corresponding PC5 Relay RLC channel.

[0278] Example K4 corresponds to case 4 above.

[0279] The following issue exists regarding how the Intermediate Relay determines the PC5 Relay RLC channel for forwarding Remote UE SRB1. One approach is to define a default SL-RLC1 or a predefined PC5 Relay RLC channel specifically for forwarding Remote UE SRB1. Another approach is that when the current Intermediate Relay UE receives an invitation from the Remote UE or the previous Intermediate Relay UE to establish a PC5 Relay RLC channel for forwarding SRB1, it determines the configuration of the next-hop PC5 Relay RLC channel and the mapping relationship based on this configuration information. SRB1 / 2 used for forwarding Remote UEs can uniformly use the default SL-RLC1 or a dedicated predefined PC5 Relay RLC channel. After the Last Relay UE receives the Remote UE's SRB1, it sends the Remote UE's SRB1 to the base station according to the mapping relationship between the Remote UE SRB and the Uu Relay RLC channel configured by the base station.

[0280] The above examples illustrate how to achieve data transmission between a remote terminal and access network devices in a multi-hop U2N scenario. The following examples illustrate how to guarantee QoS for each link in the relay path of a remote terminal in a multi-hop U2N scenario, and may include the following examples.

[0281] Example Z1.

[0282] The base station performs coarse-grained equal allocation based on the number of hops between the Remote UE and the Last relay UE, determines the QoS of each PC5 hop, and provides the corresponding PC5 relay RLC channel configuration.

[0283] The base station sends the configuration of the PC5 Relay RLC channel corresponding to the Remote UE's DRB to the Remote UE (via multi-hop relay forwarding). The Remote UE initiates the establishment process of the PC5 Relay RLC channel (used to send the Remote UE's DRB identifier) ​​with the First relay UE. The Remote UE sends the complete PC5 Relay RLC channel configuration received from the base station and the associated Remote UE DRB identifier to the First relay UE. After receiving this, the First relay UE establishes the corresponding receiver entity for the PC5 Relay RLC channel with the Remote UE, and further initiates the establishment process of the PC5 Relay RLC channel with the Intermediate relay UE. The First relay UE sends the complete PC5 Relay RLC channel configuration received from the Remote UE and the associated Remote UE DRB identifier to the Intermediate relay UE.

[0284] Alternatively, the base station sends the configuration of the PC5 Relay RLC channel corresponding to the Remote UE DRB to the Last relay UE. The Last relay UE initiates the establishment process of the PC5 Relay RLC channel (used to send the Remote UE DRB) with the downstream node (Intermediate relay UE). The Last relay UE sends the complete PC5 Relay RLC channel configuration received from the base station and the associated Remote UE DRB identifier to the Intermediate relay UE. Similarly, the Intermediate relay UE further sends the complete PC5 Relay RLC channel configuration received from the Last relay UE and the associated Remote UE DRB identifier to the First relay UE.

[0285] The base station needs to know the number of hops the Remote UE has reached to the base station / Last relay. The Remote UE or the Last relay UE can report the number of hops to the base station.

[0286] Example Z1 corresponds to the sixth information mentioned above, which indicates the configuration of the PC5 relay radio link control (RLC) channel of the link between the remote terminal and the first relay terminal in the relay path. The configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path can be used for other links in the relay path.

[0287] Example Z2.

[0288] There is no restriction on the base station to equally allocate QoS between the Remote UE and the Last relay UE for each hop. The base station can flexibly configure the PC5 relay RLC channel and the corresponding PDB for each hop.

[0289] The base station sends the PC5 Relay RLC channel configuration for each hop corresponding to the Remote UE's DRB (each hop between the Remote UE and the Last relay) to the Remote UE (forwarded via multiple relays). The Remote UE sends the PC5 Relay RLC channel configuration for each remaining hop, excluding the configuration for the first hop (between the Remote UE and the First relay), to the First relay UE. Similarly, the First relay further sends the PC5 Relay RLC channel configuration for each remaining hop, excluding the configuration for the second hop (between the First relay and the Intermediate relay), to the Intermediate relay UE.

[0290] Alternatively, the base station sends the PC5 Relay RLC channel configuration for each hop corresponding to the Remote UE DRB (each hop between the Remote UE and the Last relay) to the Last relay UE. The Last relay UE sends the PC5 Relay RLC channel configuration for each remaining hop to the next-hop node, excluding the configuration for the PC5 Relay RLC channel between the Last relay and the Intermediate relay.

[0291] Example Z2 corresponds to the sixth information mentioned above, which indicates the configuration of the PC5 relay radio link control (RLC) channel of the link between the remote terminal and the first relay terminal in the relay path. The sixth information is also used to indicate the configuration of the PC5 relay RLC channel of other links in the relay path. The configuration of the PC5 relay RLC channel of at least one of the other links is different from the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path.

[0292] Example Z3.

[0293] The remote UE reports the PC5 link quality for each hop to assist the base station in configuring the PC5 relay RLC channel. The remote UE can obtain the PC5 link quality for each hop by carrying / adding the PC5 link quality of the previous hop during the discovery message propagation process in a multi-hop relay path discovery process. Alternatively, the remote UE can report the PC5 QoS supported by each hop to the base station.

[0294] Example Z3 corresponds to the tenth piece of information mentioned above.

[0295] Example Z4.

[0296] The base station determines the PC5 QoS configuration for each hop corresponding to the Remote UE DRB and sends this configuration to the Remote UE (except for the first hop, where the PC5 Relay RLC channel configuration is configured by the base station). The Remote UE further sends the PC5 QoS configuration for each hop (and the mapping between the Remote UE DRB and PC5 QoS configurations) to the First relay UE. Similarly, the First relay UE further sends this to the Intermediate relay UE. All Intermediate relay UEs determine the PC5 Relay RLC channel configuration based on their coverage status, the configuration in the SIB / pre-config, and the PC5 QoS configuration for each hop, and associate the Remote UE DRB identifier with that PC5 Relay RLC channel. How the base station translates the Remote UE Uu QoS into the PC5 QoS configuration for each hop is implemented by the base station.

[0297] Example Z4 corresponds to the eighth piece of information mentioned above.

[0298] Example Z5.

[0299] The base station sends the remaining PC5 QoS profile (PC5 QoS from the Remote UE to the Last relay; or PC5 QoS from the First Intermediate relay UE to the Last relay UE) to the Remote UE. The Remote UE then sends this PC5 QoS configuration to the First relay UE. The First relay UE performs QoS splitting, dividing it into the PC5 QoS configuration between the Remote UE and the First relay UE, and the remaining PC5 QoS configuration. When performing QoS splitting, the First relay UE considers the quality of adjacent PC5 hop links and the number of hops between the Remote UE and the Last relay. The First relay then sends the remaining PC5 QoS to the Second relay UE, which performs further QoS splitting. For example, after the Second relay UE performs QoS splitting, the First relay UE obtains the PC5 QoS for the second hop. The First relay UE determines the PC5 relay RLC channel configuration based on its own coverage status, the configuration in the SIB / pre-config, and the PC5 QoS configuration for each hop.

[0300] The following describes the RRC connection establishment process for multi-hop remote terminals.

[0301] Figure 6 illustrates an RRC connection establishment process for a multi-hop remote terminal according to an embodiment of this disclosure. Referring to Figure 6, the process may include the following steps:

[0302] V1. The remote terminal initiates the discovery process.

[0303] The remote terminal selects a relay path that can reach the base station through a multi-hop relay discovery process.

[0304] V2. The remote terminal initiates the PC5 connection establishment process.

[0305] After the remote terminal selects a relay path that can reach the base station through the multi-hop relay discovery process, it initiates a PC5 connection establishment process with the relay terminal in the relay path.

[0306] V3. The remote terminal sends an RRC connection establishment request message to the base station through the relay path.

[0307] V4. The base station sends an RRC establishment message to the remote terminal through the relay path.

[0308] V5, prepare PC5 and Uu relay RCL channels for SRB1.

[0309] Subsequently, the remote terminal, each relay terminal, and the base station prepare PC5 and Uu relay RCL channels for SRB1.

[0310] V6. The remote terminal sends an RRC establishment completion message to the base station through the relay path.

[0311] V7. The base station sends a security mode command to the remote terminal via a relay path.

[0312] After the RRC is established, the base station can send a security mode command to the remote terminal to instruct the remote terminal to establish a security mode.

[0313] V8: The remote terminal sends a security mode completion message to the base station via a relay path.

[0314] After establishing a secure mode, the remote terminal sends a "security mode complete" message to the base station.

[0315] V9. The base station sends an RRC reconfiguration message to the remote terminal via a relay path.

[0316] V10: The remote terminal sends an RRC reconfiguration complete message to the base station via a relay path.

[0317] V11, Prepare PC5 and Uu relay RLC channels for SRB2 / DRB.

[0318] Subsequently, the remote terminal, each relay terminal, and the base station prepare PC5 and Uu relay RLC channels for SRB2 / DRB.

[0319] Thus, the RRC connection establishment process for multi-hop remote terminals is completed.

[0320] During link handover, if the base station decides to switch the Remote UE from the multi-hop indirect path to the direct Uu link or to the single-hop indirect path, after the base station sends an RRC reconfiguration message containing the handover command to the Remote UE, or after the base station receives the Remote UE's RRC reconfiguration completion message on the new link / target link, the base station will configure each relay UE on the original multi-hop indirect path to release the Remote UE's related configurations.

[0321] Specifically, the gNB will send an RRC reconfiguration message to the Last relay UE on the original link, instructing the Last relay UE to release the bearer mapping information related to the Remote UE, as well as the Uu Relay RLC channel (if this logical channel is not used for data forwarding of other Remote UEs) and the PC5 Relay RLC channel (the PC5 Relay RLC channel between the Last relay UE and the child Intermediate relay UE, if this logical channel is not used for data forwarding of other Remote UEs).

[0322] If the Intermediate relay UE on the original link is in RRC connected state, the base station sends an RRC reconfiguration message to it, instructing the Intermediate relay UE to release the PC5 Relay RLC channel configuration and bearer mapping configuration related to the Remote UE and its neighboring relay UEs (e.g., between the Intermediate relay and the parent relay, and between the Intermediate relay and the child Intermediate relay / or the Remote UE).

[0323] If the Intermediate relay UE on the source link is in a non-RRC connected state, after receiving the RRC reconfiguration message from the base station indicating the release of the Remote UE's related configuration information, the Last relay UE sends a PC5-RRC message to the child Intermediate relay on that link. This message contains an indication to release the Remote UE's related configuration information, specifically including the Remote UE's identifier (L2 ID or Local ID) and the configuration release indication. Upon receiving this PC5-RRC message, the child Intermediate relay UE (of the Last relay UE) further sends a PC5-RRC message to its child Intermediate relay UE, indicating the release of the Remote UE's related configuration information. This process continues until the first Intermediate relay UE connected to the Remote UE releases the configuration information related to the Remote UE.

[0324] Alternatively, after receiving a link handover command from the base station, the Remote UE sends a PC5 unicast link release message to the First Intermediate relay UE. Upon receiving the PC5 unicast link release message from the Remote UE, the First Intermediate relay sends a PC5-RRC message to its parent Intermediate relay UE, containing indications for releasing the Remote UE's configuration information. Specifically, this may include the Remote UE's identifier (L2 ID or Local ID) and the configuration release indication. This parent Intermediate relay UE further sends a PC5-RRC message to its upstream relay node, instructing it to release the Remote UE's configuration information. This process continues until all Intermediate relay UEs on the source link have released their Remote UE configuration information.

[0325] The above primarily describes the solution provided in this disclosure from the perspective of interaction between various nodes. It is understood that each node, such as a remote terminal, a first relay terminal, or an access network device, includes corresponding hardware structures and / or software modules to perform the aforementioned functions. Those skilled in the art should readily recognize that, based on the algorithmic steps of the examples described in conjunction with the embodiments disclosed herein, this disclosure can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this disclosure.

[0326] This disclosure embodiment can divide the remote terminal, the first relay terminal, or the access network device into functional modules according to the above method embodiment. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one functional module. The integrated module can be implemented in hardware or software. It should be noted that the module division in this disclosure embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods. The following description uses the example of dividing each functional module according to each function.

[0327] Figure 7 is a block diagram of a communication device according to an embodiment of the present disclosure. As shown in Figure 7, the communication device 40 includes an acquisition unit 401 and a transmission unit 402.

[0328] The communication device 40 can be the first relay terminal or a chip within the first relay terminal. When the communication device 40 is used to implement the functions of the first relay terminal in the above embodiments, each unit is specifically used to implement the following functions.

[0329] The acquisition unit 401 is used to acquire the identity identifier of the remote terminal; here, the remote terminal communicates with the access network device through the first relay terminal.

[0330] The sending unit 402 is used to send the identity identifier of the remote terminal to the access network device;

[0331] The acquisition unit 401 is also used to receive the local identifier of the remote terminal from the access network device.

[0332] In some embodiments, the acquisition unit 401 is specifically used to receive first information sent by the second relay terminal, the first information including the identity identifier of the remote terminal, the second relay terminal being the next-level relay terminal of the first relay terminal in the relay path of the remote terminal; and to acquire the identity identifier of the remote terminal based on the first information.

[0333] In some embodiments, the acquisition unit 401 is specifically used to receive a first data packet sent by a remote terminal, the first data packet being used to carry second information, the second information being used to request connection with the access network device; and to acquire the identity identifier of the remote terminal based on the first data packet.

[0334] In some embodiments, the sending unit 402 is further configured to send a first data packet to the access network device.

[0335] In some embodiments, the sending unit 402 is further configured to send a second data packet to the access network device. The second data packet carries second information and has a first header added to it. The first header includes the local identifier of the remote terminal.

[0336] In some embodiments, the acquisition unit 401 is specifically used to acquire the identity identifier of the remote terminal based on the second information.

[0337] In some embodiments, the acquisition unit 401 is further configured to receive a third data packet from the access network device, the third data packet being used to carry third information, the third information being used to establish a connection with a remote terminal.

[0338] In some embodiments, the sending unit 402 is further configured to send a third data packet and fourth information to a second relay terminal, wherein the second relay terminal is the next-level relay terminal of the first relay terminal in the relay path of the remote terminal, and the fourth information includes the identity identifier of the remote terminal and the local identifier of the remote terminal.

[0339] In some embodiments, the sending unit 402 is further configured to send a fourth data packet to the second relay terminal. The fourth data packet carries third information and has a second header added to it. The second header includes the identity identifier of the remote terminal. The second relay terminal is the next-level relay terminal of the first relay terminal in the relay path of the remote terminal.

[0340] In some embodiments, the sending unit 402 is further configured to send a third data packet by the second relay terminal, wherein the second relay terminal is the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

[0341] In some embodiments, the sending unit 402 is further configured to send a third data packet to a second relay terminal, the second relay terminal being the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

[0342] In some embodiments, the sending unit 402 is further configured to send fifth information to the access network device, the fifth information being used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first relay terminal.

[0343] In some embodiments, the acquisition unit 401 is further configured to receive sixth information, which is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

[0344] In some embodiments, the acquisition unit 401 is further configured to receive seventh information from the second relay terminal, the seventh information being used to indicate the PC5 service quality configuration between the second relay terminal and the first relay terminal, the second relay terminal being the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

[0345] Figure 8 is a block diagram of another communication device provided according to an embodiment of the present disclosure. As shown in Figure 8, the communication device 50 includes a transmitting unit 501 and a receiving unit 502.

[0346] The communication device 50 can be the aforementioned remote terminal or a chip within the remote terminal. When the communication device 50 is used to implement the functions of the remote terminal in the above embodiments, each unit is specifically used to implement the following functions.

[0347] The sending unit 501 is used to send second information to the access network device through the first relay terminal. The second information is used to request a connection with the access network device. The relay path of the remote terminal includes at least one relay terminal, and the first relay terminal is one of the at least one relay terminal.

[0348] The receiving unit 502 is used to receive third information from the access network device, and the third information is used to establish a connection with the remote terminal.

[0349] In some embodiments, the sending unit 501 is specifically used to send a first data packet to the access network device, the first data packet being used to carry second information.

[0350] In some embodiments, the receiving unit 502 is specifically configured to receive a third data packet from the access network device, the third data packet being used to carry third information.

[0351] In some embodiments, the receiving unit 502 is further configured to receive sixth information from the access network device, the sixth information being used to indicate the configuration of the PC5 relay radio link control (RLC) channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

[0352] The sending unit 501 is also used to send the sixth information to the first relay terminal, and the remote terminal communicates with the access network equipment through the first relay terminal.

[0353] In some embodiments, the receiving unit 502 is further configured to receive eighth information from the access network device, the eighth information being used to indicate the configuration of the PC5 service quality of each link in the relay path of the remote terminal;

[0354] The sending unit 501 is also used to send a ninth message to the first relay terminal in the relay path. The ninth message is used to indicate the PC5 service quality configuration of other links in the relay path other than the link between the remote terminal and the first relay terminal.

[0355] In some embodiments, the sending unit 501 is further configured to send tenth information to the access network device, the tenth information being used to indicate the PC5 link quality of each link in the relay path of the remote terminal.

[0356] Figure 9 is a block diagram of another communication device provided according to an embodiment of the present disclosure. As shown in Figure 9, the communication device 60 includes a receiving unit 601 and a transmitting unit 602.

[0357] The communication device 60 can be the access network device described above or a chip within the access network device. When the communication device 60 is used to implement the functions of the access network device in the above embodiments, each unit is specifically used to implement the following functions.

[0358] The receiving unit 601 is used to receive the identity identifier of the remote terminal sent by the first relay terminal, and the remote terminal communicates with the access network equipment through the first relay terminal;

[0359] The sending unit 602 is used to send the local identifier of the remote terminal to the access network device.

[0360] In some embodiments, the receiving unit 601 is further configured to receive second information sent by the remote terminal through the first relay terminal, the second information being used to request the establishment of a connection with the access network device;

[0361] The sending unit 602 is also used to send third information to the remote terminal, the third information being used to establish a connection with the remote terminal.

[0362] In some embodiments, the receiving unit 601 is specifically used to receive a first data packet sent by a remote terminal through a first relay terminal, the first data packet being used to carry second information.

[0363] In some embodiments, the sending unit 602 is specifically used to send a third data packet to a remote terminal through a first relay terminal, the third data packet being used to carry third information.

[0364] In some embodiments, the receiving unit 601 is further configured to receive fifth information, which is used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first relay terminal.

[0365] In some embodiments, the receiving unit 601 is further configured to receive tenth information from a remote terminal, the tenth information being used to indicate the PC5 link quality of each link in the relay path of the remote terminal.

[0366] In some embodiments, the sending unit 602 is further configured to send sixth information, which is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

[0367] In some embodiments, the sending unit 602 is further configured to send eighth information, which is used to indicate the configuration of the PC5 service quality of each link in the relay path of the remote terminal.

[0368] It should be noted that the units in Figures 7 to 9 can also be called modules; for example, the transmitting unit can be called a transmitting module. Furthermore, in the embodiments shown in Figures 7 to 9, the names of the units may not be those shown in the figures; for example, the transmitting unit can also be called a communication unit, and the receiving unit can also be called a communication unit.

[0369] If the units in Figures 7 to 9 are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this disclosure, in essence, or the parts that contribute to the prior art, or all or part of the technical solutions, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this disclosure. Storage media for storing computer software products include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0370] When the communication device 40, communication device 50, or communication device 60 implements the functions of the integrated module in hardware, a block diagram of a communication device is provided according to an embodiment of this disclosure. As shown in FIG10, the communication device 70 includes: a processor 702, a communication interface 703, and a bus 704. In some embodiments, the communication device 70 may further include a memory 701.

[0371] Processor 702 may implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with this disclosure. Processor 702 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with this disclosure. Processor 702 may also be a combination that implements computational functions, such as a combination of one or more microprocessors, a digital signal processor (DSP), and a microprocessor.

[0372] The communication interface 703 is used to connect to other devices via a communication network. This communication network can be Ethernet, wireless access network, wireless local area network (WLAN), etc.

[0373] The memory 701 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), disk storage medium or other magnetic storage device, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but is not limited thereto.

[0374] In one possible implementation, the memory 701 can exist independently of the processor 702. The memory 701 can be connected to the processor 702 via a bus 704 and is used to store instructions or program code. When the processor 702 calls and executes the instructions or program code stored in the memory 701, it can implement the communication method provided in the embodiments of this disclosure.

[0375] In another possible implementation, the memory 701 can also be integrated with the processor 702.

[0376] Bus 704 can be an extended industry standard architecture (EISA) bus, etc. Bus 704 can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in Figure 10, but this does not mean that there is only one bus or one type of bus.

[0377] Through the above description of the implementation methods, those skilled in the art can clearly understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the remote terminal, the first relay terminal, or the access network device can be divided into different functional modules to complete all or part of the functions described above.

[0378] This disclosure also provides a computer-readable storage medium. All or part of the processes in the above method embodiments can be executed by computer instructions instructing related hardware. The program can be stored in the computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The computer-readable storage medium can also be an external storage device for the remote terminal, the first relay terminal, or the access network device, such as a pluggable hard drive, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the remote terminal, the first relay terminal, or the access network device. Further, the computer-readable storage medium can include both internal storage units of the remote terminal, the first relay terminal, or the access network device and external storage devices. The computer-readable storage medium is used to store the computer program and other programs and data required by the remote terminal, the first relay terminal, or the access network device. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0379] This disclosure also provides a computer program product comprising a computer program that, when run on a computer, causes the computer to perform any of the communication methods provided in the above embodiments.

[0380] Although this disclosure has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed disclosure. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce a good effect.

[0381] Although this disclosure has been described in conjunction with specific features and embodiments, it will be apparent that various modifications and combinations can be made therein without departing from the spirit and scope of this disclosure. Accordingly, this specification and drawings are merely exemplary illustrations of the disclosure as defined by the appended claims and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this disclosure. It is obvious that those skilled in the art can make various alterations and modifications to this disclosure without departing from its spirit and scope. Thus, this disclosure is also intended to include any such modifications and modifications that fall within the scope of the claims of this disclosure and their equivalents.

[0382] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions within the technical scope disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A communication method, wherein, Applied to the first relay terminal, including: Obtain the identity identifier of the remote terminal; the remote terminal communicates with the access network device through the first relay terminal; Send the remote terminal's identity identifier to the access network device; Receive the local identifier of the remote terminal from the access network device.

2. The method according to claim 1, wherein, The identity identifier of the remote terminal includes at least one of the following: L2 sign; User information identifier; Temporary mobile user identifier; Random number.

3. The method according to claim 1 or 2, wherein, The process of obtaining the identity identifier of the remote terminal includes: The system receives first information sent by a second relay terminal, the first information including the identity identifier of the remote terminal, and the second relay terminal is the next-level relay terminal of the first relay terminal in the relay path of the remote terminal; Based on the first information, the identity identifier of the remote terminal is obtained.

4. The method according to any one of claims 1 to 3, wherein, The process of obtaining the identity identifier of the remote terminal includes: Receive a first data packet sent by the remote terminal, the first data packet being used to carry second information, the second information being used to request to establish a connection with the access network device; Based on the first data packet, the identity identifier of the remote terminal is obtained.

5. The method according to claim 4, wherein, The method further includes: The first data packet is sent to the access network device.

6. The method according to claim 4 or 5, wherein, The method further includes: A second data packet is sent to the access network device. The second data packet carries the second information and has a first header added to it. The first header includes the local identifier of the remote terminal.

7. The method according to any one of claims 4 to 6, wherein, The second information includes the identity identifier of the remote terminal; obtaining the identity identifier of the remote terminal based on the first data packet includes: Based on the second information, the identity identifier of the remote terminal is obtained.

8. The method according to any one of claims 4 to 7, wherein, The first data packet is appended with a second header, which includes the identity identifier of the remote terminal; The step of obtaining the identity identifier of the remote terminal based on the first data packet includes: Based on the second message header, the identity identifier of the remote terminal is obtained.

9. The method according to claim 8, wherein, The second header is added to the remote terminal, or to the first relay terminal in the relay path of the remote terminal.

10. The method according to claim 5 or 6, wherein, The method further includes: The system receives a third data packet from the access network device. The third data packet carries third information, which is used to establish a connection with the remote terminal.

11. The method according to claim 10, wherein, The third data packet is appended with a first header, the first header including the local identifier of the remote terminal; the method further includes: The third data packet and the fourth information are sent to the second relay terminal, which is the next-level relay terminal of the first relay terminal in the relay path of the remote terminal. The fourth information includes the identity identifier of the remote terminal and the local identifier of the remote terminal.

12. The method according to claim 10, wherein, The third data packet is appended with a first header, the first header including the local identifier of the remote terminal; the method further includes: A fourth data packet is sent to the second relay terminal. The fourth data packet carries the third information and has a second header. The second header includes the identity identifier of the remote terminal. The second relay terminal is the next-level relay terminal of the first relay terminal in the relay path of the remote terminal.

13. The method according to claim 10, wherein, The third data packet is appended with a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal; the method further includes: The third data packet is sent to a second relay terminal, which is the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

14. The method of claim 10, wherein, The third information includes the identity identifier of the remote terminal; the method further includes: The third data packet is sent to a second relay terminal, which is the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

15. The method according to any one of claims 1 to 14, wherein, The method further includes: Send a fifth message to the access network device, the fifth message being used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first relay terminal.

16. The method according to claim 1, 5, 6 or 15, wherein, The method further includes: Receive sixth information, the sixth information being used to indicate the configuration of the PC5 relay radio link control (RLC) channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

17. The method according to claim 16, wherein, The configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path can be used for other links in the relay path.

18. The method according to claim 16 or 17, wherein, The sixth piece of information is also used to indicate the configuration of the PC5 relay RLC channel of other links in the relay path, wherein the configuration of the PC5 relay RLC channel of at least one of the other links is different from the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path.

19. The method according to any one of claims 16 to 18, wherein, The sixth piece of information also includes a DRB identifier associated with the link between the relay terminal and the first relay terminal.

20. The method according to claim 1, 5, 6 or 15, wherein, The method further includes: The system receives a seventh message from a second relay terminal, the seventh message indicating the PC5 service quality configuration between the second relay terminal and the first relay terminal, the second relay terminal being the next-level relay terminal in the relay path of the first relay terminal in the remote terminal.

21. A communication method, wherein, Applied to a remote terminal, the method includes: The remote terminal sends second information to the access network device through a first relay terminal. The second information is used to request the establishment of a connection with the access network device. The relay path of the remote terminal includes at least one relay terminal, and the first relay terminal is one of the at least one relay terminal. Receive third information from the access network device, the third information being used to establish a connection with the remote terminal.

22. The method according to claim 21, wherein, Sending the second information to the access network device includes: A first data packet is sent to the access network device, the first data packet being used to carry the second information.

23. The method according to claim 21 or 22, wherein, The second information includes the identity identifier of the remote terminal.

24. The method according to claim 23, wherein, The identity identifier of the remote terminal includes at least one of the following: L2 sign; User information identifier; Temporary mobile user identifier; Random number.

25. The method according to any one of claims 22 to 24, wherein, The first data packet is appended with a second header, which includes the identity identifier of the remote terminal.

26. The method according to any one of claims 21 to 25, wherein, The receiving of third information from the access network device includes: Receive a third data packet from the access network device, the third data packet being used to carry the third information.

27. The method according to claim 26, wherein, The third data packet is appended with a first header, which includes the local identifier of the remote terminal.

28. The method according to claim 26, wherein, The third data packet is appended with a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal.

29. The method according to any one of claims 26 to 28, wherein, The third piece of information includes the identity identifier of the remote terminal.

30. The method according to any one of claims 21 to 29, wherein, The method further includes: The system receives sixth information from the access network device, the sixth information being used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal; The sixth message is sent to the first relay terminal.

31. The method according to any one of claims 21 to 30, wherein, The method further includes: The system receives eighth information from the access network device, the eighth information being used to indicate the configuration of PC5 service quality for each link in the relay path of the remote terminal; A ninth message is sent to the first relay terminal in the relay path, the ninth message being used to indicate the PC5 service quality configuration of other links in the relay path besides the link between the remote terminal and the first relay terminal.

32. The method according to any one of claims 21 to 31, wherein, The method further includes: The tenth information is sent to the access network device, and the tenth information is used to indicate the PC5 link quality of each link in the relay path of the remote terminal.

33. A communication method, wherein, Applied to access network equipment, the method includes: The system receives the identity identifier of a remote terminal sent by a first relay terminal, and the remote terminal communicates with the access network device through the first relay terminal. Send the local identifier of the remote terminal to the first relay terminal.

34. The method according to claim 33, wherein, The method further includes: Receive second information sent by the remote terminal through the first relay terminal, the second information being used to request the establishment of a connection with the access network device; Send a third message to the remote terminal, the third message being used to establish a connection with the remote terminal.

35. The method according to claim 34, wherein, Receiving the second information sent by the remote terminal through the first relay terminal includes: The system receives a first data packet sent by the remote terminal through the first relay terminal, the first data packet being used to carry the second information.

36. The method according to claim 34 or 35, wherein, The second information includes the identity identifier of the remote terminal.

37. The method of claim 35, wherein, The first data packet is appended with a second header, which includes the identity identifier of the remote terminal.

38. The method according to any one of claims 33 to 37, wherein, The identity identifier of the remote terminal includes at least one of the following: L2 sign; User information identifier; Temporary mobile user identifier; Random number.

39. The method according to any one of claims 34 to 37, wherein, Sending third information to the remote terminal includes: The third data packet is sent from the first relay terminal to the remote terminal, and the third data packet is used to carry the third information.

40. The method according to claim 39, wherein, The third data packet is appended with a first header, which includes the local identifier of the remote terminal.

41. The method according to claim 39, wherein, The third data packet is appended with a third header, which includes the local identifier of the remote terminal and the identity identifier of the remote terminal.

42. The method according to claim 39, wherein, The third piece of information includes the identity identifier of the remote terminal.

43. The method according to any one of claims 33 to 42, wherein, The method further includes: The system receives a fifth piece of information, which is used to indicate the number of hops between the remote terminal and the access network device, or to indicate the number of hops between the remote terminal and the first relay terminal.

44. The method according to any one of claims 33 to 43, wherein, The method further includes: The system receives tenth information from the remote terminal, which indicates the PC5 link quality of each link in the relay path of the remote terminal.

45. The method according to claim 33, 43 or 44, wherein, The method further includes: Send a sixth message, which is used to indicate the configuration of the PC5 relay RLC channel of the link between the remote terminal and the first relay terminal in the relay path of the remote terminal.

46. ​​The method according to any one of claims 33 to 45, wherein, The method further includes: Send an eighth message to the remote terminal, the eighth message being used to indicate the PC5 service quality configuration of each link in the relay path of the remote terminal.

47. A communication device, wherein, include: Memory and processor; Memory and processor are coupled; The memory is used to store instructions that can be executed by the processor; When the processor executes the instructions, it performs the method as described in any one of claims 1 to 46.

48. A computer-readable storage medium, wherein, The computer-readable storage medium stores computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1 to 46, wherein the computer-readable storage medium includes a non-transitory computer-readable storage medium.

49. A computer program product, wherein, The computer program product includes computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1 to 46.

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