Multicast and broadcast service establishment

Abstract

Disclosed are methods, devices, and systems for establishing a multicast and broadcast service session based on an existing tunnel between a core network node and a wireless access node. In one exemplary aspect, a wireless communication method includes: receiving, by a first communication node, a request to establish a session from a core network node. The request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services. The method includes: selecting, by the first communication node, a channel from the list of tunnels included in the request to establish a multicast and broadcast session corresponding to the session. The method also includes: transmitting, by the first communication node, a response indicating the establishment of the session to the core network node. The response includes information associated with the selected channel between the second communication node and the core network node.

Description

Technical Field

[0001] This patent document relates generally to wireless communications. Background Art

[0002] Mobile communication technologies are moving the world towards an increasingly connected and networked society. The rapid growth of mobile communications and technological advances have led to greater demands for capacity and connectivity. Other aspects such as energy consumption, equipment cost, spectrum efficiency and latency are also important to meet the needs of various communication scenarios. Various technologies are currently being discussed, including new ways to provide higher quality of service, longer battery life and improved performance. Summary of the invention

[0003] This patent document describes, among other things, techniques for enabling a Radio Access Network (RAN) node to establish a Multicast and Broadcast Service (MBS) session using an existing tunnel already established between a core network and another RAN node, thereby improving load balancing between RAN nodes and reducing signaling overhead associated with mobile devices in mobility scenarios.

[0004] In one example aspect, a wireless communication method is disclosed. The method includes: receiving, by a first communication node, a request from a core network node to establish a communication session. The request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services. The method includes: selecting, by the first communication node, a channel from the list of tunnels included in the request to establish a multicast and broadcast session corresponding to the communication session. The method also includes: transmitting, by the first communication node, to the core network node a response indicating the establishment of the communication session. The response includes information associated with the selected channel between the second communication node and the core network node.

[0005] In another example aspect, a wireless communication method is disclosed. The method includes: transmitting, by a core network node, a request to establish a communication session to a first communication node. The request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services. The method also includes: receiving, by the core network node, a response indicating the establishment of the communication session. The response includes information associated with a channel between the second communication node and the core network node selected from the list of tunnels.

[0006] In another exemplary aspect, a communication device is disclosed, wherein the device includes a processor configured to implement the above method.

[0007] In yet another exemplary aspect, a computer program storage medium is disclosed. The computer program storage medium includes code stored thereon. The code, when executed by a processor, causes the processor to implement the described method.

[0008] These and other aspects are described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 An example architecture of a fifth generation (5G) system is shown.

[0010] Figure 2 An example architecture for providing multicast and broadcast services is shown.

[0011] Figure 3 An example of transmitting multicast service data from a 5G core network to a next generation radio access network (NG-RAN) node according to the present technology is shown.

[0012] Figure 4 A 5G network deployment 400 for multicast and broadcast services (MBS) in accordance with the present technology is shown.

[0013] Figure 5 An example signaling sequence according to the present technique is shown.

[0014] Figure 6 is a flow chart representation of a method for wireless communication according to the present technology.

[0015] Figure 7 is a flow chart representation of another method for wireless communication according to the present technology.

[0016] Figure 8 An example of a wireless communication system in which the technology according to one or more embodiments of the present technology can be applied is shown.

[0017] Fig. 9 is a block diagram representation of a portion of a radio station in which techniques in accordance with one or more embodiments of the present technology may be applied. DETAILED DESCRIPTION

[0018] The section headings used in this document are intended only to improve readability and do not limit the scope of the embodiments and techniques disclosed in each section to only that section. Certain features are described using examples of fifth generation (5G) wireless protocols. However, the applicability of the disclosed techniques is not limited to only 5G wireless systems.

[0019] In telecommunications, 5G is the fifth generation technology standard for cellular networks that provides connectivity for wireless communication devices. 5G communication systems offer many network capabilities. Figure 1An example architecture 100 of a 5G system is shown. The illustrated architecture 100 includes the following network functions:

[0020] 1. Access and Mobility Management Function (AMF) 101. AMF 101 is responsible for user equipment (UE) mobility management, reachability management and / or connection management, etc. AMF terminates the radio access network (RAN) control plane (CP) N2 interface and the non-access layer (NAS) N1 interface. It also assigns the session manager (SM) NAS to the appropriate session management function (SMF) through the N11 interface.

[0021] 2. Session Management Function (SMF) 103. SMF 103 is responsible for UE Internet Protocol (IP) address allocation and management, user plane (UP) function selection and control, and / or protocol data unit (PDU) connection management.

[0022] 3. User Plane Function (UPF) 105. UPF 105 is the anchor point for intra / inter RAT mobility and the external PDU session interconnection point to the data network. UPF also routes and forwards data packets as directed from SMF. When a is in idle mode, UPF 105 buffers downlink data.

[0023] 4. Unified Data Management (UDM) 107. UDM 107 manages the subscription profile of the UE. The subscription data includes data for mobility management (e.g. restricted area), session management (e.g. quality of service profile for each slice of each data network name). The subscription data also includes slice selection parameters for AMF to select the appropriate SMF 103. AMF 101 and SMF 103 obtain subscription data from UDM 107. The subscription data is stored in a unified data repository (UDR) (not shown). UDM 107 uses such data upon receiving a request from AMF 101 or SMF 103.

[0024] 5. Policy Control Function (PCF) 109. PCF 109 generates policies for managing network behavior based on subscriptions and instructions from Application Function (AF) 111. It also provides policy rules to CP functions (e.g., AMF 101 and / or SMF 103) for implementation. PCF can access UDR to retrieve policy data.

[0025] 6. Network Open Function (NEF) (not shown). NEF is optionally deployed to exchange information between the 5G core network (also known as 5GC) and external third parties. In this case, AF 111 can store application information in UDR via NEF.

[0026] With the development of 5G technology, 5G communication systems can provide multicast broadcast services for different businesses related to public safety, autonomous driving and / or the Internet of Things (IoT). Figure 2 An example architecture for providing multicast and broadcast services is shown. The illustrated architecture 200 includes network functions such as a multicast / broadcast SMF (MB-SMF) 203 and / or a multicast / broadcast UPF (MB-UPF) 205 enhanced to support multicast / broadcast services. The architecture 200 also includes the following network functions:

[0027] 1. Multicast / Broadcast Service Function (MBSF) 207. MBSF 207 is a new network function for managing signaling for service layer capabilities. It also provides an interface for application servers or content providers.

[0028] 2. Multicast / Broadcast Service User Plane (MBSU) 209. MBSU 209 is a new entity for managing payload data of service layer capabilities. MBSU 209 can be an independent entity or collocated with MBSF or MB-UPF.

[0029] Figure 3 An example of transmitting multicast service data from a 5GC to a next generation radio access network (NG-RAN) node according to the present technology is shown. A multicast / broadcast service (MBS) includes one or more MBS quality of service (QoS) flows. After a UE has successfully joined an MBS, the 5GC may initiate the establishment of (multiple) MBS QoS flows for this UE. Two scenarios are described below:

[0030] 1. For each joined UE, MBSF triggers MB-SMF to establish one or more multicast QoS flows in a PDU session. The PDU session can be an existing PDU session, and the 5GC initiates the PDU session modification procedure. The PDU session can also be a new PDU session established by the 5GC in the PDU session setup procedure. QoS flows can be bound to UE-specific unicast tunnels. User data in these QoS flows can be transmitted from the 5GC to the UE via NG-RAN. When multiple UEs join the same MBS, the 5GC can establish a UE-specific unicast tunnel for each UE to transmit data in (multiple) QoS flows. For example, Figure 3 As shown, a unicast PDU session 311 is established for UEa 301, and a unicast PDU session 313 is established for UEb 303. A QoS flow 321 for MBS user data for UEa 301 may be bound to the unicast tunnel 311. A QoS flow 323 for MBS user data for UEb 303 may be bound to the unicast tunnel 313. The unicast tunnel may be configured with a QoS flow identifier (QFI) included in the encapsulation header of each user data packet.

[0031] 2. Alternatively, or in addition, when the 5GC decides to use multicast mode to transmit user data, a shared tunnel can be established for all UEs joining the MBS. The MBSF can trigger the MB-SMF to establish a shared multicast tunnel 315 for all UEs in the same NG-RAN node. For example, a QoS flow 325 for MBS user data of other UEs can be bound to the shared multicast tunnel 315. (Multiple) multicast QoS flows can be configured with MBS identifiers, such as temporary mobile group identifiers (TMGI), session identifiers (IDs), special QoS flow IDs. The MBS identifier can be included in the encapsulation header of each user data packet.

[0032] (Multiple) QoS flows can be bound to a unicast tunnel for each UE, or to a shared multicast tunnel. If both UE-specific unicast tunnels and shared multicast tunnels are configured, it is more desirable to transmit MBS user data on the shared tunnel. In some cases, the unicast tunnel can become a virtual tunnel without MBS user data transmission.

[0033] Figure 4 4 shows a 5G network deployment 400 for multicast and broadcast services (MBS) according to the present technology. Figure 4 As shown, 5GC (e.g., UPF) establishes an N3 tunnel with each NG-RAN node. When the network allows the UE to join the MBS service including the one or more MBS QoS flows, the UE can pre-occupy the cell belonging to NG-RAN1. If the MBS service has been established for the NG-RAN1 node, the NG-RAN1 node already has a multicast / shared N3 tunnel for transmitting user data for the MBS service. 5GC does not need to establish an N3 tunnel with the UE again. However, if a multicast / shared N3 tunnel has not been established for the NG-RAN1 node, the 5GC establishes a tunnel so that user data for the MBS service can be transmitted from the network node (e.g., UPF) to the UE. The shared tunnel includes at least a tunnel identifier and a downlink (DL) address anchored at the corresponding RAN node. For example, Figure 4 The three shared tunnels have different tunnel IDs and different downlink addresses to allow user data to be transmitted to NG-RAN1, NG-RAN2 and NG-RAN3 respectively.

[0034] With the development of wireless communication technology, UE can achieve dual connectivity by establishing two connections with two different RAN nodes. Dual connectivity allows UE to aggregate data streams and improve UE mobility. This patent document discloses a technology that can be implemented in various embodiments to enable two RAN nodes to use the same tunnel (e.g., UE-specific unicast or shared multicast tunnel) for MBS user data transmission, thereby achieving load balancing between RAN nodes. The disclosed technology is applicable to dual connectivity scenarios as well as single connectivity scenarios. For example, the disclosed technology can be applied to reduce signaling overhead when UE mobility occurs between the two RAN nodes, so as to eliminate the need for switching anchor nodes and / or switching procedures.

[0035] Figure 5 An example signaling sequence 500 according to the present technology is shown. Connecting NG-RAN1 node (e.g., Figure 4 A UE (shown in FIG. 1 ) may establish a new connection with the NG-RAN4 node to achieve dual connectivity. The UE wants to join an MBS including one or more MBS QoS flows. A tunnel (e.g., a UE-specific unicast tunnel or a shared N3 tunnel) has been established between the NG-RAN1 node and the 5GC. However, there is no existing tunnel between the NG-RAN4 node and the 5GC. The following operations may be performed to enable NG-RAN4 to establish or use a tunnel to transmit MBS user data.

[0036] Operation 501: After the core network receives a setup request from the UE (e.g., when the UE moves to the coverage area of ​​the NG-RAN4 node), the core network (e.g., 5GC or UPF / AMP in the 5GC) transmits a request message to the NG-RAN4 node for establishing a session. The request message may be a PDU session resource setting request message, a PDU session resource modification request message, or a new type of request message.

[0037] The request message may include information about one or more unicast PDU sessions to be established for the UE(s) (e.g., Figure 3 As shown). The request message includes the uplink (UL) unicast tunnel address of the core network node to allow the establishment of (multiple) unicast PDU sessions. For each unicast PDU session, a corresponding MBS session (i.e., a mapped MBS session) can be established accordingly. The request message may include mapping information between the PDU unicast session and the MBS session. Each UE-specific PDU session includes one or more QoS flows associated with the UE-specific PDU session context. Information about the UE-specific PDU session may include at least a PDU session ID, a QoS flow list, and information about the unicast user data tunnel.

[0038] The request message may also include a list of tunnels that have been established between the core network and other RAN nodes. Each tunnel in the shared tunnel list is identified by a dedicated tunnel ID. For example, the list may include the following information: Tunnel ID1->{CN, NG-RAN1}, Tunnel ID2->{CN, NG-RAN2}, and Tunnel ID3->{CN, NG-RAN3}.

[0039] Operation 502: After receiving the request message from the core network, the NG-RAN4 node determines how to establish the accepted MBS session. The NG-RAN4 node may determine to establish the MBS session between the core network and itself. In some cases, the NG-RAN4 node may find that it is already carrying a heavy load. In order to achieve better load balancing, the NG-RAN4 node may determine to use one of the existing tunnels to establish the MBS session based on the list of shared tunnels that have been established between the core network and other RAN nodes, thereby reducing and / or eliminating the additional load brought by establishing a new tunnel.

[0040] Operation 503: If the NG-RAN4 node determines to use an existing tunnel (e.g., tunnel ID1->{CN, NG-RAN1}) to establish an MBS session, the NG-RAN4 node may initiate a procedure with the NG-RAN1 node to notify the NG-RAN1 node of the MBS session. The procedure may be a secondary node (SN) addition procedure or an SN modification procedure. The notification may help the NG-RAN1 node to release the tunnel / session at an appropriate time. For example, the tunnel of NG-RAN1 initially includes five QoS flows for five UEs, respectively. After the five UEs leave the coverage area of ​​the NG-RAN1 node, the tunnel should still be maintained by NG-RAN1 because it is used by the NG-RAN4 node for MBS user data transmission. In addition, the NG-RAN1 node may notify the NG-RAN4 node of the downlink unicast tunnel address and / or shared tunnel address at the NG-RAN1 node.

[0041] Operation 504: The NG-RAN4 node sends a response message to the core network in response to the request message received in operation 501. The response message may be a PDU session resource setting response message, a PDU session resource modification response message, or a new type of response message. The NG-RAN4 node reports the downlink unicast tunnel address and / or shared tunnel address of the NG-RAN1 node to allow the core network to route the MBS session user data via the NG-RAN1 node.

[0042] Operation 505: The core network now transmits user data to the NG-RAN4 node via the tunnel of NG-RAN1. In some embodiments, NG-RAN4 reports only the unicast tunnel address of NG-RAN1 to the core network. NG-RAN4 may then receive user data via the unicast user data tunnel of NG-RAN1. In some embodiments, NG-RAN4 reports the shared tunnel address of NG-RAN1, or the unicast tunnel address and the shared multicast tunnel address of NG-RAN1 to the core network. NG-RAN4 may then receive user data via the shared multicast tunnel of NG-RAN1, as it prefers to use this shared channel when it is available.

[0043] In some embodiments, the UE can be dual-connected to NG-RAN1 and NG-RAN4. In some embodiments, the UE is only connected to NG-RAN4. However, NG-RAN4 can still utilize existing tunnels (e.g., tunnels of neighboring RAN nodes) to transmit MBS user data, thereby improving UE mobility handling. For example, when the UE moves from NG-RAN4 to NG-RAN1, using the tunnel of NG-RAN1 for MBS user data transmission can eliminate the need for anchor node switch or hand-over procedures.

[0044] Figure 6 6 is a flow chart of a method 600 for wireless communication according to the present technology. The method 600 includes: at operation 610, a first communication node (e.g., Figure 5 The NG-RAN4 shown in the figure receives a request to establish a communication session from a core network node. The request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services. The method 600 includes: at operation 620, the first communication node selects a channel from the list of tunnels included in the request to establish a multicast and broadcast session corresponding to the communication session. The method 600 also includes: at operation 630, the first communication node transmits a response indicating the establishment of the communication session to the core network node. The response includes information associated with the selected channel between the second communication node and the core network node.

[0045] In some embodiments, the communication session comprises a protocol data unit (PDU) session specific to a mobile device. In some embodiments, the mobile device is dually connected to the first communication node and the second communication node. In some embodiments, each tunnel in the tunnel list is identified by a dedicated tunnel identifier.

[0046] In some embodiments, the method includes: receiving, by the first communication node, from the second communication node, at least one of the following: a unicast tunnel address of the second communication node or a multicast tunnel address of the second communication node. In some embodiments, the information associated with the selected channel between the second communication node and the core network node includes at least one of the following: the unicast tunnel address of the second communication node or the multicast tunnel address of the second communication node. In some embodiments, the method further includes: receiving, by the first communication node, from the core network node via the second communication node, data for the multicast and broadcast session.

[0047] Figure 7 7 is a flow diagram representation of a method 700 for wireless communication according to the present technology. The method 700 includes: at operation 710, a core network node transmits a request to establish a communication session to a first communication node. The request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services. The method 700 includes: at operation 720, the core network node receives a response indicating the establishment of the communication session. The response includes information associated with a channel between the second communication node and the core network node selected from the tunnel list.

[0048] In some embodiments, the communication session comprises a protocol data unit (PDU) session specific to a mobile device. In some embodiments, the mobile device is dually connected to the first communication node and the second communication node. In some embodiments, each tunnel in the tunnel list is identified by a dedicated tunnel identifier.

[0049] In some embodiments, the information associated with the channel between the second communication node and the core network node includes at least one of the following: a unicast tunnel address of the second communication node or a multicast tunnel address of the second communication node. In some embodiments, the method further includes: transmitting, by the core network node, data for the multicast and broadcast to the first communication node via the second communication node.

[0050] Figure 8An example of a wireless communication system 800 in which techniques according to one or more embodiments of the present technology may be applied is shown. The wireless communication system 1200 may include one or more base stations (BSs) 805a, 805b, one or more wireless devices 810a, 810b, 810c, 810d, and a core network 825. The base stations 805a, 805b may provide wireless services to the wireless devices 810a, 810b, 810c, and 810d in one or more wireless sectors. In some implementations, the base stations 805a, 805b include directional antennas to generate two or more directional beams to provide wireless coverage in different sectors.

[0051] The core network 825 can communicate with one or more base stations 805a, 805b. The core network 825 provides connections with other wireless communication systems and wired communication systems. The core network may include one or more service subscription databases to store information related to the subscribed wireless devices 810a, 810b, 810c and 810d. The first base station 805a can provide wireless services based on a first wireless access technology, and the second base station 805b can provide wireless services based on a second wireless access technology. Depending on the deployment scenario, base stations 805a and 805b can be located at the same location or installed separately on site. Wireless devices 810a, 810b, 810c and 810d can support a variety of different wireless access technologies. The techniques and embodiments described in this document can be implemented by the base stations of the wireless devices described in this document.

[0052] Fig. 9 905 is a block diagram representation of a portion of a radio station in which the technology according to one or more embodiments of the present technology can be applied. A radio station 905, such as a base station or a wireless device (or wireless device), may include a processor electronic device 910, such as a microprocessor that implements one or more of the wireless technologies described in this document. The radio station 905 may include a transceiver electronic device 915 for sending and / or receiving wireless signals through one or more communication interfaces such as an antenna 920. The radio station 905 may include other communication interfaces for transmitting and receiving data. The radio station 905 may include one or more memories (not explicitly shown) configured to store information such as data and / or instructions. In some implementations, the processor electronic device 910 may include at least a portion of the transceiver electronic device 915. In some embodiments, the radio station 905 is used to implement at least some of the disclosed technologies, modules, or functions. In some embodiments, the radio station 905 may be configured to perform the methods described herein.

[0053] It should be understood that this document discloses techniques that can be implemented in various embodiments to improve load balancing between RAN nodes and reduce signaling mobility associated with mobile devices in mobility scenarios. The disclosed embodiments and other embodiments, the modules and functional operations described in this document can be implemented in digital electronic circuits or in computer software, firmware, or hardware (including the structures disclosed in this document and their structural equivalents), or a combination of one or more of them. The disclosed embodiments and other embodiments can be implemented as one or more computer program products, that is, one or more modules of computer program instructions encoded on a computer-readable medium for execution by a data processing device or for controlling the operation of a data processing device. The computer-readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a material combination that affects a machine-readable propagation signal, or a combination of one or more of them. The term "data processing device" covers devices, equipment and machines for processing data, including, for example, a programmable processor, a computer or multiple processors or computers. In addition to hardware, the device may include code that creates an execution environment for the computer program in question, for example, code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, eg, a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus.

[0054] A computer program (also referred to as a program, software, software application, script or code) can be written in any form of programming language, including compiled or interpreted languages, and the computer program can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for a computing environment. A computer program does not necessarily correspond to a file in a file system. The program can be stored in a portion of a file that retains other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordination files (e.g., files storing one or more modules, subroutines, or parts of code). A computer program can be deployed to execute on a computer or on multiple computers located at a site or distributed across multiple sites and interconnected by a communication network.

[0055] The processes and logic flows described in this document can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by an apparatus, and the apparatus can also be implemented as a special-purpose logic circuit system, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC).

[0056] Processors suitable for executing computer programs include, by way of example, general and special purpose microprocessors, and any one or more processors of any type of digital computer. Generally speaking, the processor will receive instructions and data from a read-only memory or a random access memory or both. The basic elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include one or more mass storage devices (e.g., magnetic disks, magneto-optical disks, or optical disks) for storing data, or be operatively coupled to receive data from a mass storage device or to transfer data to a mass storage device, or both. However, a computer need not have such a device. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, by way of example, semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD ROM and DVD-ROM disks. The processor and memory may be supplemented by or incorporated into a dedicated logic circuit.

[0057] Although this patent document contains many specific contents, these specific contents should not be interpreted as limitations on the scope of any invention or the content that may be claimed, but should be interpreted as descriptions of features that may be specific to a particular embodiment of a particular invention. Certain features described in the context of various embodiments in this patent document may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented separately in multiple embodiments, or in any suitable sub-combination. In addition, although features may be described above as working in certain combinations, and even initially claimed as such, in some cases, one or more features in the claimed combination may be deleted from this combination, and the claimed combination may point to a variant of a sub-combination or a sub-combination.

[0058] Similarly, although operations are described in a particular order in the drawings, this should not be understood as requiring that the operations must be performed in the particular order or sequence shown, or that all of the operations shown must be performed, in order to achieve the desired results. Moreover, the separation of various system components in the embodiments described in this patent document should not be understood as requiring such separation in all embodiments.

[0059] Only some implementations and examples are described, and other implementations, improvements, and variations may be made based on what is described and illustrated in this patent document.

Claims

1. A method for wireless communication, comprising: Receiving, by a first communication node, a request for establishing a communication session from a core network node, wherein the request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services; selecting, by the first communication node, a tunnel from the tunnel list included in the request to establish a multicast and broadcast session corresponding to the communication session; and A response is transmitted by the first communication node to the core network node indicating establishment of the communication session, the response including information associated with the selected tunnel between a second communication node and the core network node.

2. The method according to claim 1, wherein: The communication session includes a protocol data unit (PDU) session specific to the mobile device.

3. The method according to claim 2, wherein: The mobile device is dual-connected to the first communication node and the second communication node.

4. The method according to claim 1, wherein: Each tunnel in the tunnel list is identified by a dedicated tunnel identifier.

5. The method according to claim 1, comprising: At least one of the following items is received by the first communication node from the second communication node: a unicast tunnel address of the second communication node or a multicast tunnel address of the second communication node.

6. The method according to claim 5, wherein: The information associated with the selected tunnel between the second communication node and the core network node comprises at least one of: the unicast tunnel address of the second communication node or the multicast tunnel address of the second communication node.

7. The method according to claim 1, further comprising: Data for the multicast and broadcast session is received by the first communication node from the core network node via the second communication node.

8. A method for wireless communication, comprising: Transmitting, by the core network node to the first communication node, a request for establishing a communication session, wherein the request includes a list of tunnels established between the core network node and other communication nodes for providing multicast and broadcast services; A response is received by the core network node indicating establishment of the communication session, the response including information associated with a tunnel between a second communication node and the core network node selected from the tunnel list.

9. The method according to claim 8, wherein: The communication session includes a protocol data unit (PDU) session specific to the mobile device.

10. The method according to claim 9, wherein: The mobile device is dual-connected to the first communication node and the second communication node.

11. The method according to claim 8, wherein: Each tunnel in the tunnel list is identified by a dedicated tunnel identifier.

12. The method according to claim 8, wherein: The information associated with the tunnel between the second communication node and the core network node comprises at least one of: a unicast tunnel address of the second communication node or a multicast tunnel address of the second communication node.

13. The method according to claim 8, further comprising: Data for the multicast and broadcast is transmitted from the core network node to the first communication node via the second communication node.

14. A communication device comprising a processor, the processor being configured to implement the method according to any one of claims 1 to 13.

15. A computer program product having stored thereon codes which, when executed by a processor, cause the processor to carry out the method according to any one of claims 1 to 13.

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