CN117981362A

CN117981362A - Method and device for communication through relay terminal and terminal

Info

Publication number: CN117981362A
Application number: CN202180102523.5A
Authority: CN
Inventors: 卢飞; 郭雅莉
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2021-11-26
Filing date: 2021-11-26
Publication date: 2024-05-03
Also published as: WO2023092482A1

Abstract

The embodiment of the application provides a method and a device for communication through a relay terminal, and the terminal, wherein the method comprises the following steps: the relay terminal receives a data unit sent by a first terminal, and forwards the data unit to at least one second terminal; the data unit is transmitted between the first terminal and the relay terminal in a first communication mode, and the data unit is transmitted between the relay terminal and the at least one second terminal in a second communication mode; the first communication mode is a unicast communication mode, and the second communication mode is a multicast communication mode or a broadcast communication mode; or the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode.

Description

Method and device for communication through relay terminal and terminal

Technical Field

The embodiment of the application relates to the technical field of mobile communication, in particular to a method and a device for communication through a relay terminal and a terminal.

Background

For near field communication in broadcast or multicast mode, only direct communication between two terminals with proximity Services (Proximity-based Services) capability is supported, i.e. two terminals need to be in a relatively close range, one of the terminals sends broadcast or multicast, and the other terminal listens to broadcast or multicast. If the distance between two terminals is large, the other terminal cannot hear the broadcast or multicast.

Disclosure of Invention

The embodiment of the application provides a method and a device for communication through a relay terminal, the terminal, a chip, a computer readable storage medium, a computer program product and a computer program.

The method for communication through the relay terminal provided by the embodiment of the application comprises the following steps:

the relay terminal receives a data unit sent by a first terminal, and forwards the data unit to at least one second terminal;

The data unit is transmitted between the first terminal and the relay terminal in a first communication mode, and the data unit is transmitted between the relay terminal and the at least one second terminal in a second communication mode; the first communication mode is a unicast communication mode, and the second communication mode is a multicast communication mode or a broadcast communication mode; or the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode.

The communication device provided by the embodiment of the application is applied to a relay terminal, and comprises:

A receiving unit, configured to receive a data unit sent by a first terminal;

A sending unit, configured to forward the data unit to at least one second terminal;

The terminal provided by the embodiment of the application comprises a processor and a memory. The memory is used for storing a computer program, and the processor is used for calling and running the computer program stored in the memory to execute the method for communication through the relay terminal.

The chip provided by the embodiment of the application is used for realizing the method for communication through the relay terminal.

Specifically, the chip includes: and a processor for calling and running the computer program from the memory, so that the device mounted with the chip executes the above-mentioned method for communication through the relay terminal.

The computer readable storage medium provided by the embodiment of the application is used for storing a computer program, and the computer program enables a computer to execute the method for communication through the relay terminal.

The computer program product provided by the embodiment of the application comprises computer program instructions, wherein the computer program instructions enable a computer to execute the method for communication through the relay terminal.

The computer program provided by the embodiment of the application, when running on a computer, causes the computer to execute the method for communication through the relay terminal.

According to the technical scheme, the first terminal sends the data unit to be relayed to the relay terminal in a unicast communication mode, and the relay terminal forwards the received data unit to at least one second terminal in a multicast communication mode or a broadcast communication mode; or the first terminal sends the data unit needing to be relayed to the relay terminal through a multicast communication mode or a broadcast communication mode, and the relay terminal forwards the received data unit to a second terminal through a unicast communication mode. Therefore, under the condition that the distance between the first terminal and at least one second terminal is far, the communication between the first terminal and at least one second terminal can be realized, and the problem that the distance between the terminals is far and broadcasting or multicasting cannot be monitored is solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute a limitation on the application. In the drawings:

FIG. 1 is a schematic diagram of an application scenario according to an embodiment of the present application;

FIG. 2 is a schematic diagram of another application scenario of an embodiment of the present application;

fig. 3-1 is a schematic flow diagram of a broadcast or multicast mode of near field communication;

Fig. 3-2 is a schematic diagram of relay by a relay UE;

Fig. 4 is a flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application;

Fig. 5 is a flow chart II of a method for communication through a relay terminal according to an embodiment of the present application;

fig. 6 is a flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application;

fig. 7 is a flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application;

Fig. 8 is a flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application;

Fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

Fig. 10 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 11 is a schematic structural view of a chip of an embodiment of the present application.

Detailed Description

The following description of the technical solutions according to the embodiments of the present application will be given with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Fig. 1 is a schematic diagram of an application scenario according to an embodiment of the present application.

As shown in fig. 1, communication system 100 may include a terminal 110 and a network device 120. Network device 120 may communicate with terminal 110 over the air. Multi-service transmission is supported between the terminal 110 and the network device 120.

It should be understood that embodiments of the present application are illustrated by way of example only with respect to communication system 100, and embodiments of the present application are not limited thereto. That is, the technical solution of the embodiment of the present application may be applied to various communication systems, for example: long term evolution (Long Term Evolution, LTE) systems, LTE time division duplex (Time Division Duplex, TDD), universal mobile telecommunications system (Universal Mobile Telecommunication System, UMTS), internet of things (Internet of Things, ioT) systems, narrowband internet of things (Narrow Band Internet of Things, NB-IoT) systems, enhanced machine type communications (ENHANCED MACHINE-Type Communications, eMTC) systems, 5G communication systems (also known as New Radio (NR) communication systems), or future communication systems, etc.

In the communication system 100 shown in fig. 1, the network device 120 may be an access network device in communication with the terminal 110. The access network device may provide communication coverage for a particular geographic area and may communicate with terminals 110 (e.g., UEs) located within the coverage area.

The network device 120 may be an evolved base station (Evolutional Node B, eNB or eNodeB) in a long term evolution (Long Term Evolution, LTE) system, or a next generation radio access network (Next Generation Radio Access Network, NG RAN) device, or a base station (gNB) in a NR system, or a radio controller in a cloud radio access network (Cloud Radio Access Network, CRAN), or the network device 120 may be a relay station, an access point, a vehicle device, a wearable device, a hub, a switch, a bridge, a router, or a network device in a future evolved public land mobile network (Public Land Mobile Network, PLMN), etc.

Terminal 110 may be any terminal including, but not limited to, a terminal that employs a wired or wireless connection with network device 120 or other terminals.

For example, the terminal 110 may refer to an access terminal, user Equipment (UE), subscriber unit, subscriber station, mobile station, remote terminal, mobile device, user terminal, wireless communication device, user agent, or User Equipment. An access terminal may be a cellular telephone, a cordless telephone, a session initiation protocol (Session Initiation Protocol, SIP) phone, an IoT device, a satellite handset, a wireless local loop (Wireless Local Loop, WLL) station, a Personal digital assistant (Personal DIGITAL ASSISTANT, PDA), a handset with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal in a 5G network or a terminal in a future evolution network, etc.

The terminal 110 may be used for Device-to-Device (D2D) communication.

The wireless communication system 100 may further comprise a core network device 130 in communication with the base station, which core network device 130 may be a 5G core,5gc device, e.g. an access and mobility management function (ACCESS AND Mobility Management Function, AMF), further e.g. an authentication server function (Authentication Server Function, AUSF), further e.g. a user plane function (User Plane Function, UPF), further e.g. a session management function (Session Management Function, SMF). Optionally, the Core network device 130 may also be a packet Core evolution (Evolved Packet Core, EPC) device of the LTE network, for example, a session management function+a data gateway (Session Management Function +core PACKET GATEWAY, SMF +pgw-C) device of the Core network. It should be appreciated that SMF+PGW-C may perform the functions performed by both SMF and PGW-C. In the network evolution process, the core network device may also call other names, or form new network entities by dividing the functions of the core network, which is not limited in this embodiment of the present application.

Communication may also be achieved by establishing connections between various functional units in the communication system 100 through a next generation Network (NG) interface.

For example, the terminal establishes an air interface connection with the access network device through an NR interface, and is used for transmitting user plane data and control plane signaling; the terminal can establish control plane signaling connection with AMF through NG interface 1 (N1 for short); an access network device, such as a next generation radio access base station (gNB), can establish a user plane data connection with a UPF through an NG interface 3 (N3 for short); the access network equipment can establish control plane signaling connection with AMF through NG interface 2 (N2 for short); the UPF can establish control plane signaling connection with the SMF through an NG interface 4 (N4 for short); the UPF can interact user plane data with the data network through an NG interface 6 (N6 for short); the AMF may establish a control plane signaling connection with the SMF through NG interface 11 (N11 for short); the SMF may establish a control plane signaling connection with the PCF via NG interface 7 (N7 for short).

Fig. 1 illustrates one base station, one core network device, and two terminals, alternatively, the wireless communication system 100 may include a plurality of base station devices and may include other numbers of terminals within the coverage area of each base station, which is not limited by the embodiment of the present application.

It should be noted that fig. 1 is only an exemplary system to which the present application is applicable, and of course, the method shown in the embodiment of the present application may be applicable to other systems. Furthermore, the terms "system" and "network" are often used interchangeably herein. The term "and/or" is herein merely an association relationship describing an associated object, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship. It should also be understood that, in the embodiments of the present application, the "indication" may be a direct indication, an indirect indication, or an indication having an association relationship. For example, a indicates B, which may mean that a indicates B directly, e.g., B may be obtained by a; it may also indicate that a indicates B indirectly, e.g. a indicates C, B may be obtained by C; it may also be indicated that there is an association between a and B. It should also be understood that "corresponding" mentioned in the embodiments of the present application may mean that there is a direct correspondence or an indirect correspondence between the two, may mean that there is an association between the two, and may also be a relationship between an instruction and an indicated, configured, or the like. It should also be understood that "predefined" or "predefined rules" mentioned in the embodiments of the present application may be implemented by pre-storing corresponding codes, tables or other means that may be used to indicate relevant information in devices (e.g., including terminals and network devices), and the present application is not limited to the specific implementation thereof. Such as predefined may refer to what is defined in the protocol. It should be further understood that, in the embodiment of the present application, the "protocol" may refer to a standard protocol in the field of communications, and may include, for example, an LTE protocol, an NR protocol, and related protocols applied in a future communication system, which is not limited by the present application.

Fig. 2 is a schematic diagram of another application scenario of an embodiment of the present application.

As shown in fig. 2, the network element involved in the network system architecture includes: a User Equipment (UE), a radio access Network (Radio Access Network, RAN), a User plane function (User Plane Function, UPF), a Data Network (DN), a receive Core access and mobility tube (Core ACCESS AND Mobility Management Function, AMF), a session management function (Session Management Function, SMF), a policy control function (Policy Control function, PCF), an application function (Application Function, AF), an authentication server function (Authentication Server Function, AUSF), a Unified Data management (Unified DATA MANAGEMENT, UDM). The UE is connected with AN Access Stratum (AS) through a Uu interface, and exchanges access stratum information and wireless data transmission. The UE performs non-access stratum (NAS) connection with the AMF through an N1 interface, and interacts NAS messages. The AMF is a mobility management function in the core network, the SMF is a session management function in the core network, and the AMF is responsible for forwarding session management related messages between the UE and the SMF in addition to mobility management of the UE. The PCF is a policy management function in the core network, responsible for formulating policies related to mobility management, session management, charging, etc. for the UE. The UPF is a user plane function in the core network, performs data transmission with AN external DN through AN N6 interface, and performs data transmission with AN AN through AN N3 interface. After the UE accesses the mobile communication network through the Uu port, the PDU session is established under the control of the SMF to carry out data transmission.

It should be noted that fig. 2 is an example of a 5G network architecture, and the technical solution of the embodiment of the present application is not limited to use in a 5G network, but is also used in other mobile communication networks in the future.

In order to facilitate understanding of the technical solutions of the embodiments of the present application, the following description describes related technologies of the embodiments of the present application, and the following related technologies may be optionally combined with the technical solutions of the embodiments of the present application as alternatives, which all belong to the protection scope of the embodiments of the present application.

The Prose capable UE may multicast or broadcast data units over the PC5 interface and other Prose capable UEs may receive multicast or broadcast data units over the PC5 interface. FIG. 3-1 is a schematic flow diagram of near field communication in broadcast or multicast mode, wherein UE-1 is the transmitting side of a data unit and UE-2 through UE-n are the receiving sides of the data unit; as shown in fig. 3-1, the method comprises the following steps:

1. UE-2 to UE-n determine a target Layer 2 identity (Layer-2 ID) for reception.

2. The application layer of UE-1 provides the data units that need to be sent, optionally providing quality of service (Quality of Service, qoS) requirements.

3. The UE-1 determines a source layer 2 identity and a target layer 2 identity for transmission.

4. The UE-1 identifies the multicast or broadcast data unit according to the target layer 2.

In the above solution, the direct communication between UEs is implemented through a PC5 interface, for example: UE-1 multicasts or broadcasts data units over the PC5 interface and UE-2 through UE-n receive data units over the PC5 interface.

For near field communication in broadcast or multicast mode, only direct communication between two UEs with Prose capability is supported, that is, two UEs need to be in a relatively close range, one UE performs broadcast or multicast transmission, and the other UE performs broadcast or multicast monitoring. If the distance between two UEs is large, the other UE cannot hear the broadcast or multicast.

Therefore, the technical scheme of the embodiment of the application is provided. According to the technical scheme provided by the embodiment of the application, the data units of broadcast or multicast are forwarded through Relay UE (Relay UE). Specifically, when two UEs with Prose capability are far away and cannot directly establish communication through the PC5 interface, the relay of the communication can be performed by one relay UE with Prose capability. As shown in fig. 3-2, UE-R is a relay UE, and UE-R may directly communicate with UE1 through a PC5 interface, may also directly communicate with UE2 through a PC5 interface, and UE1 and UE2 may communicate through R-UE.

In order to facilitate understanding of the technical solution of the embodiments of the present application, the technical solution of the present application is described in detail below through specific embodiments. The above related technologies may be optionally combined with the technical solutions of the embodiments of the present application, which all belong to the protection scope of the embodiments of the present application. Embodiments of the present application include at least some of the following.

It should be noted that, in the following embodiments of the present application, the description about "terminal" may be replaced by "UE".

It should be noted that, in the following embodiments of the present application, a terminal supports Prose capability.

It should be noted that, in the following embodiments of the present application, "source layer 2 identifier" refers to a layer 2 identifier of a transmitting side corresponding to a data unit, and "destination layer 2 identifier" refers to a layer 2 identifier of a receiving side corresponding to a data unit.

Fig. 4 is a flowchart of a method for communication through a relay terminal according to an embodiment of the present application, as shown in fig. 4, the method for communication through a relay terminal includes the following steps:

Step 401: the relay terminal receives a data unit sent by a first terminal, and forwards the data unit to at least one second terminal; the data unit is transmitted between the first terminal and the relay terminal in a first communication mode, and the data unit is transmitted between the relay terminal and the at least one second terminal in a second communication mode; the first communication mode is a unicast communication mode, and the second communication mode is a multicast communication mode or a broadcast communication mode; or the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode.

In the embodiment of the application, the communication between the first terminal and at least one second terminal is realized through the forwarding of the relay terminal, wherein the distance between the first terminal and the second terminal can be longer. Here, the communication between the first terminal and the at least one second terminal is achieved by forwarding of the relay terminal, which may be achieved by:

Mode one: the relay terminal receives a data unit sent by the first terminal through a unicast communication mode, and forwards the data unit to at least one second terminal through a multicast communication mode or a broadcast communication mode.

Mode two: the relay terminal receives a data unit sent by the first terminal through a multicast communication mode or a broadcast communication mode, and forwards the data unit to a second terminal through a unicast communication mode.

In the first aspect, that is, in the case where the first communication method is a unicast communication method and the second communication method is a multicast communication method or a broadcast communication method.

In the second mode, that is, in the case where the first communication mode is a multicast communication mode or a broadcast communication mode, the second communication mode is a unicast communication mode.

The following describes the technical scheme of the embodiment of the present application in detail in combination with different cases.

Scheme one

For the case that the first communication mode is a unicast communication mode and the second communication mode is a multicast communication mode or a broadcast communication mode, the relay terminal establishes a unicast channel with the first terminal, and the unicast channel is used for unicast communication. After the unicast channel is established, the relay terminal receives the data unit sent by the first terminal through the unicast communication mode, and forwards the data unit to at least one second terminal through the multicast communication mode or the broadcast communication mode.

In some alternative embodiments, the relay terminal establishes a unicast channel with the first terminal, which may be implemented by:

The method comprises the steps that A) the relay terminal receives a direct communication request message sent by the first terminal, wherein the direct communication request message is used for requesting to establish a unicast channel; the relay terminal sends a direct communication response message to the first terminal, wherein the direct communication response message is used for indicating that unicast channel establishment is completed.

In some alternative embodiments, the direct communication request message carries information related to broadcast communication or information related to broadcast communication; the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier, a destination layer 2 identifier, a ProSe service identifier and a destination layer 2 identifier; the broadcast communication related information includes at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.

Accordingly, the relay terminal forwards the data unit to at least one second terminal through a multicast communication mode or a broadcast communication mode, which can be realized by the following modes:

the relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on the information carried in the direct communication request message and/or the first configuration information; the relay terminal forwards the data unit to at least one second terminal in a broadcast communication mode based on the destination layer 2 identifier, or forwards the data unit to at least one second terminal in a multicast communication mode based on the destination layer 2 identifier and the multicast IP address.

Here, the first configuration information is preconfigured or configured by a first network function network element. In some alternative embodiments, the first network function network element is a policy control function network element, or a close-range management network element, or a close-range application server.

In some optional embodiments, the first configuration information includes multicast communication related information or broadcast communication related information; the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier and a destination layer 2 identifier; the broadcast communication related information includes: and a mapping relation between the ProSe service identification and the destination layer 2 identification.

Scheme II

Mode B) the relay terminal sends a direct communication request message to the first terminal, where the direct communication request message is used to request establishment of a unicast channel; the relay terminal receives a direct communication response message sent by the first terminal, wherein the direct communication response message is used for indicating that the unicast channel establishment is completed.

In some alternative embodiments, the direct communication response message carries information related to broadcast communication or information related to broadcast communication; the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier, a destination layer 2 identifier, a ProSe service identifier and a destination layer 2 identifier; the broadcast communication related information includes at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.

The relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on information and/or first configuration information carried in the direct communication response message; the relay terminal forwards the data unit to at least one second terminal in a broadcast communication mode based on the destination layer 2 identifier, or forwards the data unit to at least one second terminal in a multicast communication mode based on the destination layer 2 identifier and the multicast IP address.

Scheme III

And in the case that the first communication mode is a multicast communication mode or a broadcast communication mode and the second communication mode is a unicast communication mode, the relay terminal establishes a unicast channel with the second terminal, and the unicast channel is used for unicast communication. After the unicast channel is established, the relay terminal receives the data unit sent by the first terminal through the multicast communication mode or the broadcast communication mode, and forwards the data unit to a second terminal through the unicast communication mode.

In some alternative embodiments, the relay terminal establishes a unicast channel with the second terminal, which may be implemented by:

Mode C) the relay terminal sends a direct communication request message to the second terminal, where the direct communication request message is used to request to establish a unicast channel; the relay terminal receives a direct communication response message sent by the second terminal, wherein the direct communication response message is used for indicating that the unicast channel is established.

Accordingly, the relay terminal forwards the data unit to a second terminal through a unicast communication mode, which can be realized by the following steps:

The relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on information and/or first configuration information carried in the direct communication response message; and the relay terminal forwards the data unit received on the destination layer 2 identifier to the second terminal in a unicast communication mode, or forwards the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal in a unicast communication mode.

Scheme IV

Mode D) the relay terminal receives a direct communication request message sent by the second terminal, where the direct communication request message is used to request to establish a unicast channel; and the relay terminal sends a direct communication response message to the second terminal, wherein the direct communication response message is used for indicating that the unicast channel establishment is completed.

The relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on the information carried in the direct communication request message and/or the first configuration information; and the relay terminal forwards the data unit received on the destination layer 2 identifier to the second terminal in a unicast communication mode, or forwards the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal in a unicast communication mode.

The following describes the technical scheme of the embodiment of the present application with reference to specific application examples.

Application example 1

Fig. 5 is a second flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application, as shown in fig. 5, where the method for performing communication through a relay terminal includes the following steps:

step 501: the first network function network element issues a close range policy configuration to the relay terminal and the terminals 1 to 3.

Here, the relay terminal, the terminals 1 to 3 are configured with a short-range policy configuration, that is, the first configuration information in the above-described scheme of the present application. The close range policy configuration may be pre-configured or may also be issued by the first network function network element.

Fig. 5 illustrates an example of the first network function network element issuing a close range policy configuration. As an example, the first network function element may be a PCF or a close-range management element located in the core network, where the close-range policy configuration may be sent by the PCF or the close-range management element to the terminal through an AMF, for example, may be sent to the terminal through a message such as a terminal configuration update message, a downlink NAS message, or the like. As an example, the first network function network element may also be a short range application server, by which the short range policy configuration may be sent to the terminal by means of an application layer message.

As an example, the close range policy configuration includes multicast communication related information including at least one of: the mapping relation between the application Layer group identifier (Application Layer Group ID), the ProSe Layer 2 group identifier (ProSe Layer-2 Group ID), the multicast IP address (ProSe Group IP multicast address), the ProSe service identifier (ProSe ID) and the destination Layer 2 identifier. The application layer group identifier is used for indicating an application layer group to which the terminal belongs. ProSe layer 2 group identity is used to represent the destination layer 2 identity used when the application layer provides an application layer group identity.

As an example, the close range policy configuration includes broadcast communication related information including: and a mapping relation between the ProSe service identification and the destination layer 2 identification.

Step 502: the terminal 1 transmits a direct communication request message to the relay terminal.

Here, the terminal 1 allocates a source layer 2 identifier for transmitting the direct communication request message, and transmits the direct communication request message carrying the source layer 2 identifier to the relay terminal.

Wherein the terminal 1 carries information related to the broadcast communication or information related to the broadcast communication in the direct communication request message according to the close range policy configuration in step 501.

As an example, for the case where the close range policy configuration includes multicast communication related information, the direct communication request message carries the multicast communication related information including at least one of: application layer group identification, proSe layer 2 group identification, multicast IP address, proSe service identification, destination layer 2 identification, mapping relation between ProSe service identification and destination layer 2 identification.

As an example, for the case where the close range policy configuration includes broadcast communication related information, the direct communication request message carries broadcast communication related information including at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.

Step 503: the relay terminal returns a direct communication response message to the terminal 1.

Here, the direct communication response message carries QoS flow (QoS flow) information, IP address, and the like. In this way, the unicast channel between the terminal 1 and the relay terminal is established.

Step 504: the terminal 1 transmits the data unit to the relay terminal by unicast communication.

Step 505: the relay terminal determines to relay the data unit.

Here, the relay terminal determines to relay the data unit by the multicast communication method or the broadcast communication method. Specifically, the relay terminal may determine the destination layer 2 identifier and the multicast IP address corresponding to the multicast communication according to the information related to the multicast communication in step 501 or step 502, and allocate the source layer 2 identifier for the multicast communication. Or the relay terminal may determine the destination layer 2 identifier corresponding to the broadcast communication according to the information related to the broadcast communication in step 501 or step 502 and allocate the source layer 2 identifier for the broadcast communication.

Step 506: and the relay terminal forwards the data unit through a multicast communication mode or a broadcast communication mode according to the determined destination layer 2 identifier and/or the multicast IP address.

Application instance two

Fig. 6 is a flowchart third of a method for performing communication through a relay terminal according to an embodiment of the present application, as shown in fig. 6, where the method for performing communication through a relay terminal includes the following steps:

Step 601: the first network function network element issues a close range policy configuration to the relay terminal and the terminals 1 to 3.

Fig. 6 illustrates an example of the first network function network element issuing a close range policy configuration. As an example, the first network function element may be a PCF or a close-range management element located in the core network, where the close-range policy configuration may be sent by the PCF or the close-range management element to the terminal through an AMF, for example, may be sent to the terminal through a message such as a terminal configuration update message, a downlink NAS message, or the like. As an example, the first network function network element may also be a short range application server, by which the short range policy configuration may be sent to the terminal by means of an application layer message.

Step 602: the relay terminal transmits a direct communication request message to the terminal 1.

Here, the relay terminal allocates a source layer 2 identifier for transmitting the direct communication request message, and transmits the direct communication request message carrying the source layer 2 identifier to the terminal 1.

Step 603: the terminal 1 returns a direct communication response message to the relay terminal.

Wherein, the terminal 1 carries information related to the broadcast communication or information related to the broadcast communication in the direct communication response message according to the close range policy configuration in step 601.

As an example, for the case where the close range policy configuration includes multicast communication related information, the direct communication response message carries the multicast communication related information including at least one of: application layer group identification, proSe layer 2 group identification, multicast IP address, proSe service identification, destination layer 2 identification, mapping relation between ProSe service identification and destination layer 2 identification.

As an example, for the case where the close range policy configuration includes broadcast communication related information, the direct communication response message carries broadcast communication related information including at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.

Step 604: the terminal 1 transmits the data unit to the relay terminal by unicast communication.

Step 605: the relay terminal determines to relay the data unit.

Here, the relay terminal determines to relay the data unit by the multicast communication method or the broadcast communication method. Specifically, the relay terminal may determine the destination layer 2 identifier and the multicast IP address corresponding to the multicast communication according to the information related to the multicast communication in step 601 or step 603, and allocate the source layer 2 identifier for the multicast communication. Or the relay terminal may determine the destination layer 2 identifier corresponding to the broadcast communication according to the broadcast communication related information in step 601 or step 603 and allocate the source layer 2 identifier for the broadcast communication.

Step 606: and the relay terminal forwards the data unit through a multicast communication mode or a broadcast communication mode according to the determined destination layer 2 identifier and/or the multicast IP address.

Application example three

Fig. 7 is a flowchart of a method for performing communication through a relay terminal according to an embodiment of the present application, as shown in fig. 7, where the method for performing communication through a relay terminal includes the following steps:

step 701: the first network function network element issues a close range policy configuration to the relay terminal and the terminals 1 to 3.

Fig. 7 illustrates an example of the first network function network element issuing a close range policy configuration. As an example, the first network function element may be a PCF or a close-range management element located in the core network, where the close-range policy configuration may be sent by the PCF or the close-range management element to the terminal through an AMF, for example, may be sent to the terminal through a message such as a terminal configuration update message, a downlink NAS message, or the like. As an example, the first network function network element may also be a short range application server, by which the short range policy configuration may be sent to the terminal by means of an application layer message.

Step 702: the relay terminal transmits a direct communication request message to the terminal 3.

Here, the relay terminal allocates a source layer 2 identifier for transmitting the direct communication request message, and transmits the direct communication request message carrying the source layer 2 identifier to the terminal 3.

Step 703: the terminal 3 returns a direct communication response message to the relay terminal.

Here, the direct communication response message carries QoS flow (QoS flow) information, IP address, and the like. In this way, the unicast channel between the terminal 3 and the relay terminal is established.

Wherein, the terminal 3 carries information related to the broadcast communication or information related to the broadcast communication in the direct communication response message according to the close range policy configuration in step 701.

Step 704: the terminal 1 transmits the data unit to the relay terminal by a multicast communication method or a broadcast communication method.

Step 705: the relay terminal determines to relay the data unit.

Here, the relay terminal determines to relay the data unit by unicast communication. Specifically, the relay terminal may determine, according to the information related to the multicast communication in step 701 or step 703, a destination layer 2 identifier and a multicast IP address corresponding to the multicast communication, and determine that the multicast data unit received on the destination layer 2 identifier and the multicast IP address needs to be forwarded. Or the relay terminal may determine, according to the information related to the broadcast communication in step 701 or step 703, the destination layer 2 identifier corresponding to the broadcast communication, and determine that the broadcasted data unit received on the destination layer 2 identifier needs to be forwarded.

Step 706: the relay terminal forwards the data unit through a unicast communication mode.

Application example four

Fig. 8 is a flowchart fifth of a method for performing communication through a relay terminal according to an embodiment of the present application, as shown in fig. 8, where the method for performing communication through a relay terminal includes the following steps:

Step 801: the first network function network element issues a close range policy configuration to the relay terminal and the terminals 1 to 3.

Fig. 8 illustrates an example of the first network function network element issuing a close range policy configuration. As an example, the first network function element may be a PCF or a close-range management element located in the core network, where the close-range policy configuration may be sent by the PCF or the close-range management element to the terminal through an AMF, for example, may be sent to the terminal through a message such as a terminal configuration update message, a downlink NAS message, or the like. As an example, the first network function network element may also be a short range application server, by which the short range policy configuration may be sent to the terminal by means of an application layer message.

Step 802: the terminal 3 transmits a direct communication request message to the relay terminal.

Here, the terminal 3 allocates a source layer 2 identifier for transmitting the direct communication request message, and transmits the direct communication request message carrying the source layer 2 identifier to the relay terminal.

Wherein, the terminal 3 carries information related to the broadcast communication or information related to the broadcast communication in the direct communication request message according to the close range policy configuration in step 801.

Step 803: the relay terminal returns a direct communication response message to the terminal 3.

Step 804: the terminal 1 transmits the data unit to the relay terminal by a multicast communication method or a broadcast communication method.

Step 805: the relay terminal determines to relay the data unit.

Here, the relay terminal determines to relay the data unit by unicast communication. Specifically, the relay terminal may determine, according to the information related to the multicast communication in step 801 or step 802, a destination layer 2 identifier and a multicast IP address corresponding to the multicast communication, and determine that the multicast data unit received on the destination layer 2 identifier and the multicast IP address needs to be forwarded. Or the relay terminal may determine, according to the information related to the broadcast communication in step 801 or step 802, the destination layer 2 identifier corresponding to the broadcast communication, and determine that the broadcasted data unit received on the destination layer 2 identifier needs to be forwarded.

Step 806: the relay terminal forwards the data unit through a unicast communication mode.

The preferred embodiments of the present application have been described in detail above with reference to the accompanying drawings, but the present application is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present application within the scope of the technical concept of the present application, and all the simple modifications belong to the protection scope of the present application. For example, the specific features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various possible combinations are not described further. As another example, any combination of the various embodiments of the present application may be made without departing from the spirit of the present application, which should also be regarded as the disclosure of the present application. For example, on the premise of no conflict, the embodiments described in the present application and/or technical features in the embodiments may be combined with any other embodiments in the prior art, and the technical solutions obtained after combination should also fall into the protection scope of the present application.

It should be further understood that, in the various method embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic of the processes, and should not constitute any limitation on the implementation process of the embodiments of the present application. Furthermore, in the embodiment of the present application, the terms "downstream", "upstream" and "sidestream" are used to indicate a transmission direction of signals or data, where "downstream" is used to indicate that the transmission direction of signals or data is a first direction from a station to a user equipment of a cell, and "upstream" is used to indicate that the transmission direction of signals or data is a second direction from the user equipment of the cell to the station, and "sidestream" is used to indicate that the transmission direction of signals or data is a third direction from the user equipment 1 to the user equipment 2. For example, "downstream signal" means that the transmission direction of the signal is the first direction. In addition, in the embodiment of the present application, the term "and/or" is merely an association relationship describing the association object, which means that three relationships may exist. Specifically, a and/or B may represent: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

Fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application, which is applied to a relay terminal, as shown in fig. 9, where the device includes:

a receiving unit 901, configured to receive a data unit sent by a first terminal;

a sending unit 902, configured to forward the data unit to at least one second terminal;

In some optional embodiments, for the case that the first communication mode is a unicast communication mode and the second communication mode is a multicast communication mode or a broadcast communication mode, the apparatus further includes:

the receiving unit 901 and the transmitting unit 902 are further configured to establish a unicast channel with the first terminal, where the unicast channel is used for unicast communication.

In some optional embodiments, the receiving unit 901 is configured to receive a direct communication request message sent by the first terminal, where the direct communication request message is used to request establishment of a unicast channel; the sending unit 902 is configured to send a direct communication response message to the first terminal, where the direct communication response message is used to indicate that unicast channel establishment is completed.

In some alternative embodiments, the apparatus further comprises: a determining unit 903, configured to determine, based on information and/or first configuration information carried in the direct communication request message, a destination layer 2 identifier corresponding to broadcast communication, or determine a destination layer 2 identifier and a multicast IP address corresponding to multicast communication; the sending unit 903 is configured to forward the data unit to at least one second terminal through a broadcast communication manner based on the destination layer 2 identifier, or forward the data unit to at least one second terminal through a multicast communication manner based on the destination layer 2 identifier and the multicast IP address.

In some optional embodiments, the sending unit 902 is configured to send a direct communication request message to the first terminal, where the direct communication request message is used to request establishment of a unicast channel; the receiving unit 901 is configured to receive a direct communication response message sent by the first terminal, where the direct communication response message is used to indicate that unicast channel establishment is completed.

In some alternative embodiments, the apparatus further comprises: a determining unit 903, configured to determine, based on information and/or first configuration information carried in the direct communication response message, a destination layer 2 identifier corresponding to broadcast communication, or determine a destination layer 2 identifier and a multicast IP address corresponding to multicast communication; the sending unit 903 is configured to forward the data unit to at least one second terminal through a broadcast communication manner based on the destination layer 2 identifier, or forward the data unit to at least one second terminal through a multicast communication manner based on the destination layer 2 identifier and the multicast IP address.

In some optional embodiments, for the case that the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode, the relay terminal forwards the data unit to a second terminal; the receiving unit 901 and the transmitting unit 902 are further configured to establish a unicast channel with the second terminal, where the unicast channel is used for unicast communication.

In some optional embodiments, the sending unit 902 is configured to send a direct communication request message to the second terminal, where the direct communication request message is used to request establishment of a unicast channel; the receiving unit 901 is configured to receive a direct communication response message sent by the second terminal, where the direct communication response message is used to indicate that unicast channel establishment is completed.

In some alternative embodiments, the apparatus further comprises: a determining unit 903, configured to determine, based on information and/or first configuration information carried in the direct communication response message, a destination layer 2 identifier corresponding to broadcast communication, or determine a destination layer 2 identifier and a multicast IP address corresponding to multicast communication; the sending unit 902 is configured to forward the data unit received on the destination layer 2 identifier to the second terminal through a unicast communication manner, or forward the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal through a unicast communication manner.

In some optional embodiments, the receiving unit 901 is configured to receive a direct communication request message sent by the second terminal, where the direct communication request message is used to request establishment of a unicast channel; the sending unit 902 is configured to send a direct communication response message to the second terminal, where the direct communication response message is used to indicate that unicast channel establishment is completed.

In some alternative embodiments, the apparatus further comprises: a determining unit 903, configured to determine, based on information and/or first configuration information carried in the direct communication request message, a destination layer 2 identifier corresponding to broadcast communication, or determine a destination layer 2 identifier and a multicast IP address corresponding to multicast communication; the sending unit 902 is configured to forward the data unit received on the destination layer 2 identifier to the second terminal through a unicast communication manner, or forward the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal through a unicast communication manner.

In some alternative embodiments, the direct communication request message carries information related to broadcast communication or information related to broadcast communication;

the multicast communication related information includes at least one of: application layer group identification, proximity service ProSe layer 2 group identification, multicast IP address, proSe service identification, destination layer 2 identification, mapping relation between ProSe service identification and destination layer 2 identification;

The broadcast communication related information includes at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.

In some alternative embodiments, the direct communication response message carries information related to broadcast communication or information related to broadcast communication;

the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier, a destination layer 2 identifier, a ProSe service identifier and a destination layer 2 identifier;

In some optional embodiments, the first configuration information includes multicast communication related information or broadcast communication related information;

the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier and a destination layer 2 identifier;

The broadcast communication related information includes: and a mapping relation between the ProSe service identification and the destination layer 2 identification.

In some alternative embodiments, the first configuration information is preconfigured or configured by a first network function network element.

In some alternative embodiments, the first network function network element is a policy control function network element, or a close-range management network element, or a close-range application server.

It should be understood by those skilled in the art that the above description of the communication apparatus according to the embodiment of the present application may be understood with reference to the description of the method for communicating through the relay terminal according to the embodiment of the present application.

Fig. 10 is a schematic block diagram of a communication device 1000 according to an embodiment of the present application. The communication device may be a terminal. The communication device 1000 shown in fig. 10 comprises a processor 1010, from which the processor 1010 may call and run a computer program to implement the method in an embodiment of the application.

Optionally, as shown in fig. 10, the communication device 1000 may also include a memory 1020. Wherein the processor 1010 may call and run a computer program from the memory 1020 to implement the methods in embodiments of the present application.

The memory 1020 may be a separate device from the processor 1010 or may be integrated with the processor 1010.

Optionally, as shown in fig. 10, the communication device 1000 may further include a transceiver 1030, and the processor 1010 may control the transceiver 1030 to communicate with other devices, and in particular, may send information or data to other devices or receive information or data sent by other devices.

The transceiver 1030 may include, among other things, a transmitter and a receiver. The transceiver 1030 may further include an antenna, the number of which may be one or more.

The communication device 1000 may specifically be a terminal according to an embodiment of the present application, and the communication device 1000 may implement corresponding processes implemented by the terminal in each method according to the embodiment of the present application, which are not described herein for brevity.

Fig. 11 is a schematic structural view of a chip of an embodiment of the present application. The chip 1100 shown in fig. 11 includes a processor 1110, and the processor 1110 may call and run a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in fig. 11, the chip 1100 may also include a memory 1120. Wherein the processor 1110 may call and run a computer program from the memory 1120 to implement the methods in embodiments of the present application.

Wherein the memory 1120 may be a separate device from the processor 1110 or may be integrated into the processor 1110.

Optionally, the chip 1100 may also include an input interface 1130. The processor 1110 may control the input interface 1130 to communicate with other devices or chips, and in particular, may obtain information or data sent by the other devices or chips.

Optionally, the chip 1100 may also include an output interface 1140. Wherein the processor 1110 may control the output interface 1140 to communicate with other devices or chips, and in particular, may output information or data to other devices or chips.

The chip can be applied to the terminal in the embodiment of the present application, and the chip can implement the corresponding flow implemented by the terminal in each method in the embodiment of the present application, which is not described herein for brevity.

It should be understood that the chips referred to in the embodiments of the present application may also be referred to as system-on-chip chips, or the like.

It should be appreciated that the processor of an embodiment of the present application may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method embodiments may be implemented by integrated logic circuits of hardware in a processor or instructions in software form. The Processor may be a general purpose Processor, a digital signal Processor (DIGITAL SIGNAL Processor, DSP), an Application SPECIFIC INTEGRATED Circuit (ASIC), an off-the-shelf programmable gate array (Field Programmable GATE ARRAY, FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. The disclosed methods, steps, and logic blocks in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be embodied directly in the execution of a hardware decoding processor, or in the execution of a combination of hardware and software modules in a decoding processor. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor reads the information in the memory and, in combination with its hardware, performs the steps of the above method.

It will be appreciated that the memory in embodiments of the application may be volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable EPROM (EEPROM), or a flash Memory. The volatile memory may be random access memory (Random Access Memory, RAM) which acts as external cache memory. By way of example, and not limitation, many forms of RAM are available, such as static random access memory (STATIC RAM, SRAM), dynamic random access memory (DYNAMIC RAM, DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate Synchronous dynamic random access memory (Double DATA RATE SDRAM, DDR SDRAM), enhanced Synchronous dynamic random access memory (ENHANCED SDRAM, ESDRAM), synchronous link dynamic random access memory (SYNCHLINK DRAM, SLDRAM), and Direct memory bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

It should be appreciated that the above memory is exemplary and not limiting, and for example, the memory in the embodiments of the present application may be static random access memory (STATIC RAM, SRAM), dynamic random access memory (DYNAMIC RAM, DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate synchronous dynamic random access memory (double DATA RATE SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (ENHANCED SDRAM, ESDRAM), synchronous connection dynamic random access memory (SYNCH LINK DRAM, SLDRAM), direct Rambus RAM (DR RAM), and the like. That is, the memory in embodiments of the present application is intended to comprise, without being limited to, these and any other suitable types of memory.

The embodiment of the application also provides a computer readable storage medium for storing a computer program. The computer readable storage medium may be applied to the terminal in the embodiment of the present application, and the computer program makes the computer execute the corresponding procedure implemented by the terminal in each method in the embodiment of the present application, which is not described herein for brevity.

The embodiment of the application also provides a computer program product comprising computer program instructions. The computer program product may be applied to the terminal in the embodiment of the present application, and the computer program instructions cause the computer to execute the corresponding processes implemented by the terminal in the methods in the embodiments of the present application, which are not described herein for brevity.

The embodiment of the application also provides a computer program. The computer program may be applied to the terminal in the embodiment of the present application, and when the computer program runs on the computer, the computer executes the corresponding flow implemented by the terminal in each method in the embodiment of the present application, which is not described herein for brevity.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

A method of communicating through a relay terminal, the method comprising:

the relay terminal receives a data unit sent by a first terminal, and forwards the data unit to at least one second terminal;

The data unit is transmitted between the first terminal and the relay terminal in a first communication mode, and the data unit is transmitted between the relay terminal and the at least one second terminal in a second communication mode; the first communication mode is a unicast communication mode, and the second communication mode is a multicast communication mode or a broadcast communication mode; or the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode.
The method of claim 1, wherein for the case where the first communication mode is a unicast communication mode and the second communication mode is a multicast communication mode or a broadcast communication mode, the method further comprises:

The relay terminal establishes a unicast channel with the first terminal, wherein the unicast channel is used for unicast communication.
The method of claim 2, wherein the relay terminal establishes a unicast channel with the first terminal, comprising:

the relay terminal receives a direct communication request message sent by the first terminal, wherein the direct communication request message is used for requesting to establish a unicast channel;

The relay terminal sends a direct communication response message to the first terminal, wherein the direct communication response message is used for indicating that unicast channel establishment is completed.
A method according to claim 3, wherein the relay terminal forwarding the data unit to at least one second terminal, comprising:

the relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on the information carried in the direct communication request message and/or the first configuration information;

the relay terminal forwards the data unit to at least one second terminal in a broadcast communication mode based on the destination layer 2 identifier, or forwards the data unit to at least one second terminal in a multicast communication mode based on the destination layer 2 identifier and the multicast IP address.
The method of claim 2, wherein the relay terminal establishes a unicast channel with the first terminal, comprising:

the relay terminal sends a direct communication request message to the first terminal, wherein the direct communication request message is used for requesting to establish a unicast channel;

The relay terminal receives a direct communication response message sent by the first terminal, wherein the direct communication response message is used for indicating that the unicast channel establishment is completed.
The method of claim 5, wherein the relay terminal forwarding the data unit to at least one second terminal comprises:

The relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on information and/or first configuration information carried in the direct communication response message;

the relay terminal forwards the data unit to at least one second terminal in a broadcast communication mode based on the destination layer 2 identifier, or forwards the data unit to at least one second terminal in a multicast communication mode based on the destination layer 2 identifier and the multicast IP address.
The method of claim 1, wherein, for the case where the first communication mode is a multicast communication mode or a broadcast communication mode, the second communication mode is a unicast communication mode, the relay terminal forwards the data unit to a second terminal; the method further comprises the steps of:

the relay terminal establishes a unicast channel with the second terminal, wherein the unicast channel is used for unicast communication.
The method of claim 7, wherein the relay terminal establishes a unicast channel with the second terminal, comprising:

The relay terminal sends a direct communication request message to the second terminal, wherein the direct communication request message is used for requesting to establish a unicast channel;

The relay terminal receives a direct communication response message sent by the second terminal, wherein the direct communication response message is used for indicating that the unicast channel is established.
The method of claim 8, wherein the relay terminal forwarding the data unit to at least one second terminal comprises:

The relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on information and/or first configuration information carried in the direct communication response message;

And the relay terminal forwards the data unit received on the destination layer 2 identifier to the second terminal in a unicast communication mode, or forwards the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal in a unicast communication mode.
The method of claim 7, wherein the relay terminal establishes a unicast channel with the second terminal, comprising:

The relay terminal receives a direct communication request message sent by the second terminal, wherein the direct communication request message is used for requesting to establish a unicast channel;

And the relay terminal sends a direct communication response message to the second terminal, wherein the direct communication response message is used for indicating that the unicast channel establishment is completed.
The method of claim 10, wherein the relay terminal forwarding the data unit to at least one second terminal comprises:

the relay terminal determines a destination layer 2 identifier corresponding to broadcast communication or determines a destination layer 2 identifier and a multicast IP address corresponding to multicast communication based on the information carried in the direct communication request message and/or the first configuration information;

And the relay terminal forwards the data unit received on the destination layer 2 identifier to the second terminal in a unicast communication mode, or forwards the data unit received on the destination layer 2 identifier and the multicast IP address to the second terminal in a unicast communication mode.
The method of any of claims 3, 4, 10, 11, wherein the direct communication request message carries information related to broadcast communication or information related to broadcast communication;

the multicast communication related information includes at least one of: application layer group identification, proximity service ProSe layer 2 group identification, multicast IP address, proSe service identification, destination layer 2 identification, mapping relation between ProSe service identification and destination layer 2 identification;

The broadcast communication related information includes at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.
The method of any of claims 5, 6, 8, 9, wherein the direct communication response message carries information related to broadcast communication or information related to broadcast communication;

the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier, a destination layer 2 identifier, a ProSe service identifier and a destination layer 2 identifier;

The broadcast communication related information includes at least one of: proSe service identity, destination layer 2 identity, mapping relation between ProSe service identity and destination layer 2 identity.
The method of any of claims 4,6, 9, 11, wherein the first configuration information comprises multicast communication related information or broadcast communication related information;

the multicast communication related information includes at least one of: applying a mapping relation among a layer group identifier, a ProSe layer 2 group identifier, a multicast IP address, a ProSe service identifier and a destination layer 2 identifier;

The broadcast communication related information includes: and a mapping relation between the ProSe service identification and the destination layer 2 identification.
The method of any of claims 4,6, 9, 11, 14, wherein the first configuration information is preconfigured or first network function network element configured.
The method of claim 15, wherein the first network function element is a policy control function element, or a close-range management element, or a close-range application server.
A communication apparatus applied to a relay terminal, the apparatus comprising:

A receiving unit, configured to receive a data unit sent by a first terminal;

A sending unit, configured to forward the data unit to at least one second terminal;

The data unit is transmitted between the first terminal and the relay terminal in a first communication mode, and the data unit is transmitted between the relay terminal and the at least one second terminal in a second communication mode; the first communication mode is a unicast communication mode, and the second communication mode is a multicast communication mode or a broadcast communication mode; or the first communication mode is a multicast communication mode or a broadcast communication mode, and the second communication mode is a unicast communication mode.
A terminal, comprising: a processor and a memory for storing a computer program, the processor being adapted to invoke and run the computer program stored in the memory to perform the method of any of claims 1 to 16.
A chip, comprising: a processor for calling and running a computer program from a memory, causing a device on which the chip is mounted to perform the method of any one of claims 1 to 16.
A computer readable storage medium storing a computer program for causing a computer to perform the method of any one of claims 1 to 16.
A computer program product comprising computer program instructions for causing a computer to perform the method of any one of claims 1 to 16.
A computer program which causes a computer to perform the method of any one of claims 1 to 16.