WO2022236448A1

WO2022236448A1 - A method of mbs session creation, and system and apparatus thereof

Info

Publication number: WO2022236448A1
Application number: PCT/CN2021/092246
Authority: WO
Inventors: Zhendong Li; Jinguo Zhu; Xiaojian YAN
Original assignee: Zte Corporation
Priority date: 2021-05-08
Filing date: 2021-05-08
Publication date: 2022-11-17
Also published as: CN117356075A

Abstract

A wireless communication method for use in a network function is disclosed. The method comprises transmitting, to a multicast broadcast session management function, a session establishment request associated with a multicast broadcast service (MBS) session, receiving an indication associated with an establishment of the MBS session, and transmitting, to a policy control function, a session association request associated with the MBS session.

Description

A Method of MBS Session Creation, and System and Apparatus thereof

This document is directed generally to wireless communications.

There is quite a big difference between multicast and broadcast service policy and charging control (MBS PCC) procedure and unicast packet data unit (PDU) session PCC procedure. This difference causes logic and proceeding differences in the 5G network for unicast PDU sessions and MBS sessions. It also creates complexity and inconsistency in the 5G network.

This document relates to methods, systems, and devices for the MBS session, and in particular to methods, systems, and devices for establishing the MBS session.

The present disclosure relates to a wireless communication method for use in a network function. The method comprises:

transmitting, to a multicast broadcast session management function, a session establishment request associated with a multicast broadcast service, MBS, session,

receiving an indication associated with an establishment of the MBS session, and

transmitting, to a policy control function, a session association request associated with the MBS session.

Various embodiments may preferably implement the following features:

Preferably, the establishment is associated with a policy association which is associated with the MBS session.

Preferably, the establishment is associated with a policy association between the multicast broadcast session management function and the policy control function.

Preferably, the indication is received in a session establishment response from the multicast broadcast session management function.

Preferably, the indication is received from a binding support function.

Preferably, the method further comprises transmitting, to the binding support function, a subscription request associated with the MBS session.

Preferably, the wireless communication further comprises:

transmitting, to a binding support function, a discovery request associated with the MBS session, and

retrieving, from the binding support function, information of the policy control function.

Preferably, the indication comprises information of the policy control function.

Preferably, the wireless communication method further comprises transmitting, to the multicast broadcast session management function, a request associated with the MBS session by transmitting the request to the policy control function

Preferably, the network function comprises at least one of an application function or a network exposure function.

The present disclosure relates to a wireless communication method for use in a multicast broadcast session management function. The method comprises:

receiving, from a network function, a session establishment request associated with a multicast broadcast service, MBS, session,

establishing, with a policy control function, a policy association associated with the MBS session, and

transmitting, to the network function, an indication of an establishment of the policy association.

Various embodiments may preferably implement the following features:

Preferably, the wireless communication method further comprises receiving, from the policy control function, a request associated with the MBS session.

The present disclosure relates to a wireless communication method for use in a binding support function. The method comprises:

receiving, from a policy control function, a register request associated with a multicast broadcast service, MBS, session and the policy control function, and

transmitting, to a network function, an indication associated with an establishment of the MBS session.

Various embodiments may preferably implement the following features:

Preferably, the establishment is associated with a policy associated between the multicast broadcast session management function and a policy control function.

Preferably, the wireless communication method further comprises receiving, from the network function, a subscription request associated with the MBS session.

Preferably, the wireless communication method further comprises:

receiving, from the network function, a discovery request associated with the MBS session, and

transmitting, to the network function, information associated with the policy control function.

The present disclosure relates to wireless device comprising a network function. The wireless device comprises a communication unit which is configured to:

transmit, to a multicast broadcast session management function, a session establishment request associated with a multicast broadcast service, MBS, session,

receive an indication associated with an establishment of the MBS session, and

transmit, to a policy control function, a session association request associated with the MBS session.

Various embodiments may preferably implement the following feature:

Preferably, the wireless device further comprises a processor configured to perform any of aforementioned wireless communication methods.

The present disclosure relates to wireless device comprising a policy control function. The wireless device comprises:

a communication unit, configured to receive, from a network function, a session establishment request associated with a multicast broadcast service, MBS, session, and

a processor, configured to establish, with a policy control function, a policy association associated with the MBS session, and

wherein the communication unit is further configured to transmit, to the network function, an indication of an establishment of the policy association.

Various embodiments may preferably implement the following feature:

Preferably, the processor is further configured to perform any of aforementioned wireless communication methods.

The present disclosure relates to wireless device comprising a binding support function. The wireless device comprises a communication unit which is configured to:

receive, from a policy control function, a register request associated with a multicast broadcast service, MBS, session and the policy control function, and

transmit, to a network function, an indication associated with an establishment of the MBS session.

Various embodiments may preferably implement the following feature:

The present disclosure relates to a computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement a wireless communication method recited in any one of foregoing methods.

The exemplary embodiments disclosed herein are directed to providing features that will become readily apparent by reference to the following description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while remaining within the scope of the present disclosure.

Thus, the present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. Additionally, the specific order and/or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based upon design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be re-arranged while remaining within the scope of the present disclosure. Thus, those of ordinary skill in the art will understand that the methods and techniques disclosed herein present various steps or acts in a sample order, and the present disclosure is not limited to the specific order or hierarchy presented unless expressly stated otherwise.

The above and other aspects and their implementations are described in greater detail in the drawings, the descriptions, and the claims.

FIG. 1 shows a schematic diagram of a network architecture according to an embodiment of the present disclosure.

FIG. 2 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 3 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 4 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 5 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 6 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 7 shows a schematic diagram of a procedure according to an embodiment of the present disclosure.

FIG. 8 shows an example of a schematic diagram of a wireless terminal according to an embodiment of the present disclosure.

FIG. 9 shows an example of a schematic diagram of a wireless network node according to an embodiment of the present disclosure.

FIG. 10 shows a flowchart of a method according to an embodiment of the present disclosure.

FIG. 11 shows a flowchart of a method according to an embodiment of the present disclosure.

FIG. 12 shows a flowchart of a method according to an embodiment of the present disclosure.

FIG. 1 shows a schematic diagram of a network architecture according to an embodiment of the present disclosure. The network architecture may provide the MBS. There are two types of MBS session: Broadcast MBS session and Multicast MBS session. In an embodiment, the MBS session refers to the multicast MBS session in the present disclosure. The network architecture shown in FIG. 1 comprises two types of network functions, i.e., common network functions and MBS particular network functions, which are illustrated in the following.

Common Network functions (NFs) are:

1. User equipment (UE) accessing 5 ^th generation system (5GS) obtains services via an NG-RAN and interacts with an Access and Mobility Control Function (AMF) of the core network via NAS signaling.

2. NG-RAN (i.e. 5G Radio Access Network)

The NG-RAN is responsible for air interface resource scheduling and air interface connection management of the network to which the UE accesses. In the present disclosure, the NG-RAN (node) may refer to RAN (node) .

3. AMF (Access and Mobility Management function)

The AMF includes the following functionalities: registration management, connection management, reachability management and mobility management. The AMF also performs the access authentication and access authorization. The AMF is the NAS security termination and relays the SM NAS between the UE and the SMF, etc.

4. SMF (Session Management function)

The SMF includes the following functionalities: session management (e.g. session establishment, modify and release) , UE internet protocol (IP) address allocation &management, selection and control of user plane (UP) function, downlink data notification, etc.

5. UPF (User plane function)

The UPF includes the following functionalities: anchor point for intra-/inter-RAT mobility, packet routing &forwarding, traffic usage reporting, quality of service (QoS) handling for the UP, downlink packet buffering and downlink data notification triggering, etc.

6. UDM (Unified Data Management)

The UDM manages the subscription profile for the UEs. The subscription includes the data used for mobility management, session management. The AMF and SMF get the subscription from the UDM.

7. PCF (Policy Control Function)

The PCF includes the following functionality: supporting unified policy framework to govern network behavior and providing policy rules to control plane function (s) to enforce the policy rules. In the present disclosure, the PCF may be equal to multicast broadcast PCF (MB-PCF) .

8. NEF (Network Exposure Function)

The NEF is deployed optionally for exchanging information between the 5G core network (5GC) and an external third party.

9. AF/AS (Application Function/Application Server) .

The AF/AS provides the services over the 5GS.

MBS particular network functions:

1. MB-SMF (multicast-broadcast SMF)

The MB-SMF is responsible for MBS session management, including: QoS control, configuring the MB-UPF, interacting with SMF to modify PDU session associated with MBS session, interacting with RAN (via AMF and SMF) to establish data transmission resources between MB-UPF and RAN nodes, etc.

2. MB-UPF (multicast-broadcast UPF)

The MB-UPF is responsible for packet filtering of incoming downlink packets for multicast and broadcast flows, QoS enforcement, delivery of multicast and broadcast data to the RAN nodes, etc.

In an embodiment, the multicast MBS session/service is identified by an MBS session ID. There are two kinds of MBS session ID:

-TMGI (Temporary Mobile Group Identity) ; and

-SSM (Source Specific Multicast) address.

In embodiments of the present disclosure, the MBS session ID, the TMGI and the SSM address are equivalent.

To enable the multicast MBS service, the 5G network shall initiate the MBS session configuration in a first step.

FIG. 2 shows an example on how the 5G network configures the multicast MBS session according to an embodiment of the present disclosure. For simplicity and a better understanding, unrelated steps have been omitted in FIG. 2.

At step 201 the AF sends an allocate TMGI request message to the NEF to request the allocation of a TMGI to identify a multicast MBS session.

At step 202 the NEF discovers and selects an MB-SMF using NRF or based on the local configuration.

At step 203 the NEF sends an allocate TMGI request message to the MB-SMF. The MB-SMF allocates a TMGI and returns the TMGI to the NEF.

At step 204 the NEF responds to the AF by sending an allocate TMGI response (TMGI) message.

At step 205 the AF sends a NEF multicast MBS session request, which includes the TMGI, QoS requirements, UE authorization information, etc.

At step 206 the NEF uses TMGI to check with the NRF to find the MB-SMF which serves the MBS session.

At step 207 the NEF requests the MB-SMF to configure the MBS session and provides MBS session ID (i.e. TMGI) and the QoS requirements etc.

At step 208 the MB-SMF sends a SM MBS policy association request to the MB-PCF with the MBS session ID, the AF identifier, and the QoS requirements.

At step 209 the MB-PCF registers at the BSF that it handles the multicast session. It provides the MBS session ID and the PCF ID (or the PCF set ID) to the BSF. The BSF stores the association between the MBS session ID and the PCF ID (or the PCF set ID) .

At step 210 the MB-PCF responds with a SM MBS policy association response with policies for the MBS session.

At step 211 the MB-SMF responds the result of the MBS session configuration to the NEF.

At step 212 the NEF responds to the AF.

At step 213 the AF may perform a service announcement to the UE.

The steps 205 to 212 are the PCC procedure for the MBS session. However, this procedure is different to the one for unicast PDU session for the UE.

FIG. 3 shows an example on a PCC procedure for a unicast PDU session. For simplicity and a better understanding, unrelated steps have been omitted in FIG. 3.

At step 301 the UE initiates the PDU session establishment.

At step 302 the SMF/UPF allocates the IP address for the PDU session. The SMF determines that the PCC authorization is required and requests to establish an SM policy association with the PCF by invoking a Npcf_SMPolicyControl_Create operation, including IP address of PDU Session.

At step 303 the PCF invokes a Nbsf_management_register service operation to register the PCF ID and the PDU session IP address.

At step 304 the PCF sends an SM policy association response to the SMF by invoking a Npcf_SMPolicyControl_Create response.

At step 305 the AF sends a request to the NEF. The UE IP address is included in the request.

In an embodiment of the present disclosure, the NEF is not needed for the trust domain, i.e. the AF may contact the BSF and the PCF directly.

At step 306 the NEF uses the UE IP address to check with the BSF to find the PCF, because there are multiple PCFs in the network.

At step 307 the NEF requests to establish an SM policy association with the PCF. The UE IP address is included in the request.

The PCF performs the session binding. It uses the received IP address to find the PDU session association established in step 302/304.

At steps 308 to 310, in the subsequent request, the AF sends the request to the NEF, the NEF sends a request to the PCF and the PCF sends the PCC rule to the SMF.

If the QoS requirement is included in step 305, the QoS requirement will be sent to the PCF in step 307. The PCF will then perform step 310 after step 307.

FIG. 4 shows the difference between the unicast PCC procedure and the MBS PCC procedure, wherein FIG. 4 (a) is for unicast PCC procedure and FIG. 4 (b) is for MBS PCC procedure.

With reference to FIG. 4 (a) , in the unicast PDU session PCC procedure:

At step 401 the SMF establishes the N7 session (i.e. the SM policy association between the SMF and the PCF) with the PDU session IP address.

At step 402, the PCF registers to the BSF (PCF ID, PDU session IP address) .

At step 403 the AF/NEF discovers the PCF serving the IP address.

At step 404 the AF establishes the N5 session (i.e. SM policy association between AF/NEF and PCF) .

Subsequent signaling is transmitted via a path of AF→NEF→PCF→SMF.

With reference to FIG. 4 (b) , in the MBS PCC procedure:

At step 401a the AF/NEF indicates the MB-SMF multicast session (MBS session ID) .

At step 402a the SMF establishes the N7 session (i.e. SM policy association between the SMF and the PCF) with the MBS session ID (similar to the above IP address) .

At step 403a the PCF registers to the BSF (PCF ID, MBS session ID) .

There is no N5 session in the PCC procedure shown in FIG. 4 (b) .

Subsequent signaling is transmitted via a path of AF→NEF→MB-SMF←→PCF.

FIG. 5 shows how the 5G network configures the multicast MBS session, especially the PCC part, according to an embodiment of the present disclosure. For simplicity and a better understanding, unrelated steps have been omitted in FIG. 5.

Steps 501 to 506 are same as steps 201 to 206.

At step 501 the AF sends an allocate TMGI request message to the NEF to request allocation of a TMGI to identify a multicast MBS session.

At step 502 the NEF discovers and selects an MB-SMF using the NRF or based on the local configuration.

At step 503 the NEF sends an allocate TMGI request message to the MB-SMF. The MB-SMF allocates a TMGI and returns the TMGI to the NEF.

At step 504 the NEF responds to the AF by sending an allocate TMGI response (TMGI) message.

At step 505 the AF sends a NEF multicast MBS session request, which includes the TMGI, QoS requirements, UE authorization information, etc.

At step 506 the NEF uses TMGI to check with the NRF to find the MB-SMF, which serves the MBS session.

At step 507 the NEF requests the MB-SMF to configure the MBS session and provides the MBS session ID (i.e. TMGI) .

At step 508 the MB-SMF sends a SM MBS policy association request to the MB-PCF with the MBS session ID, AF Identifier.

At step 509 the MB-PCF registers at the BSF that it handles the multicast session. It provides MBS session ID and PCF ID (or PCF set ID) to the BSF. The BSF stores the association between the MBS session ID and the PCF ID (or the PCF set ID) .

At step 510 the MB-PCF responds with a SM MBS policy association response with policies for the MBS session.

At step 511 the MB-SMF responds the result of the MBS session configuration to the NEF.

At step 512 the NEF uses the MBS session ID to check with the BSF to find the MB-PCF, because there are multiple PCFs in the network.

At step 513 the NEF requests to establish an SM policy association with the MB-PCF. The MBS session ID is included in the request.

The PCF performs the session binding. It uses the received MBS session ID to find the MBS session association (between the MB-PCF and the MB-SMF) established in step 508/510.

At step 514 the NEF responds to the AF.

In an embodiment of a trust network domain, the NEF may not be needed, i.e. the AF may contact/interact with other network functions directly as the NEF does. In other words, the AF may directly communicate/interact with the BSF and/or the PCF and/or the MB-SMF.

In the following embodiments, the interaction between the NEF and the AF is not shown for simplicity.

Next, according to embodiments of the present disclosure, it is described how the AF/NEF knows it can request the SM association with MB-PCF (i.e. step 512/513 in FIG. 5) .

FIG. 6 shows a schematic diagram of a procedure of how the AF/NEF knows it can request the SM association with MB-PCF according to an embodiment of the present disclosure.

The procedure of FIG. 6 may precede the procedure of FIG. 5. The indication is from the MB-SMF. After receiving the indication, the AF/NEF starts to establish the SM policy with the MB-PCF. For simplicity and a better understanding, unrelated steps have been omitted in FIG. 6.

Step 601 is the same as steps 501 to 506.

Step 602 is the same as step 507. The NEF requests the MB-SMF to configure the MBS session and provides the MBS session ID (i.e. TMGI) .

Step 603 is the same as steps 508 to 510.

Step 604 is the same as step 507. The MB-SMF responds the result of the MBS session configuration to the NEF. The PCF ID may be carried in this message.

If the AF/NEF receives the PCF ID in step 604, step 605 may be skipped. Otherwise, the AF/NEF uses the MBS session ID to check with the BSF to find the MB-PCF, because there are multiple PCFs in the network.

AT step 606 the AF/NEF requests to establish an SM policy association with the MB-PCF. The MBS session ID is included in the request.

The MB-PCF performs the session binding. It uses the received MBS session ID to find the MBS session association (between the MB-PCF and the MB-SMF) established in step 603.

FIG. 7 shows a schematic diagram of a procedure of how the AF/NEF knows it can request the SM association with MB-PCF according to an embodiment of the present disclosure.

The procedure of FIG. 7 may precede the procedure of FIG. 5. The AF/NEF subscribes the notification to the BSF with the MBS session ID. When the MB-PCF registers the MBS session ID to the BSF, the BSF notifies the AF/NEF. After receiving the indication, the AF/NEF starts to establish the SM policy with the MB-PCF. For simplicity and a better understanding, unrelated steps have been omitted in FIG. 7.

Step 701 is the same as step 501 to 506.

At step 702 the AF/NEF subscribes the notification to the BSF with the MBS session ID.

Step 703 is the same as step 509. The MB-PCF registers at the BSF that it handles the multicast session. It provides the MBS session ID and the PCF ID (or the PCF set ID) to the BSF. The BSF stores the association between the MBS session ID and the PCF ID (or the PCF set ID) .

At step 704 the MB-PCF notifies the AF/NEF. The PCF ID may be carried in this message.

If the AF/NEF receives the PCF ID in step 704, step 705 may be skipped. Otherwise, the AF/NEF uses the MBS session ID to check with the BSF to find the MB-PCF, because there are multiple PCFs in the network.

At step 706 the AF/NEF requests to establish an SM policy association with the MB-PCF. The MBS session ID is included in the request.

In an embodiment, when the MBS session is configured:

The AF sends the multicast session request to the NEF (with MBS session ID) .

The NEF detects the MB-SMF and requests the MB-SMF to establish a multicast session (MBS session ID) .

The MB-SMF establishes the N7 session (i.e. SM policy association between the MB-SMF and the MB-PCF) with the MBS session ID.

The PCF registers to the BSF (PCF ID, MBS session ID) .

Indicating the AF/NEF the N7 session establishment (or multicast session, or SM policy association) has been performed.

The AF/NEF checks the BSF with the MBS session ID to find the MB-PCF.

The AF/NEF requests SM policy association to the PCF (with MBS session ID) .

The PCF performs session binding using the MBS session ID (associating N5 and N7 session) .

In the subsequent signaling, the AF/NEF sends the request to the MB-PCF and the MB-PCF sends a request to the MB-SMF.

In an embodiment, for indicating the AF/NEF the N7 session establishment, the MB-SMF indicates to the NEF/AF in the multicast session request response, which may include the PCF ID or the AF/NEF subscribes the notification with the BSF with the MBS session ID. When the MB-PCF registers the PCF ID and the MBS session ID to the BSF, the BSF notifies the AF/NEF, which may include the PCF ID.

FIG. 8 relates to a schematic diagram of a wireless terminal 80 according to an embodiment of the present disclosure. The wireless terminal 80 may be a user equipment (UE) , a mobile phone, a laptop, a tablet computer, an electronic book or a portable computer system and is not limited herein. The wireless terminal 80 may include a processor 800 such as a microprocessor or Application Specific Integrated Circuit (ASIC) , a storage unit 810 and a communication unit 820. The storage unit 810 may be any data storage device that stores a program code 812, which is accessed and executed by the processor 800. Embodiments of the storage unit 812 include but are not limited to a subscriber identity module (SIM) , read-only memory (ROM) , flash memory, random-access memory (RAM) , hard-disk, and optical data storage device. The communication unit 820 may a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 800. In an embodiment, the communication unit 820 transmits and receives the signals via at least one antenna 822 shown in FIG. 8.

In an embodiment, the storage unit 810 and the program code 812 may be omitted and the processor 800 may include a storage unit with stored program code.

The processor 800 may implement any one of the steps in exemplified embodiments on the wireless terminal 80, e.g., by executing the program code 812.

The communication unit 820 may be a transceiver. The communication unit 820 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless network node (e.g. a base station) .

FIG. 9 relates to a schematic diagram of a wireless network node 90 according to an embodiment of the present disclosure. The wireless network node 90 may be a satellite, a base station (BS) , a network entity, a Mobility Management Entity (MME) , Serving Gateway (S-GW) , Packet Data Network (PDN) Gateway (P-GW) , a radio access network (RAN) node, a next generation RAN (NG-RAN) node, a gNB, an eNB, a gNB central unit (gNB-CU) , a gNB distributed unit (gNB-DU) a data network, a core network or a Radio Network Controller (RNC) , and is not limited herein. In addition, the wireless network node 90 may comprise (perform) at least one network function such as an access and mobility management function (AMF) , a session management function (SMF) , a user place function (UPF) , a policy control function (PCF) , an application function (AF) , BSF, MB-SMF, NEF, etc. The wireless network node 90 may include a processor 900 such as a microprocessor or ASIC, a storage unit 910 and a communication unit 920. The storage unit 910 may be any data storage device that stores a program code 912, which is accessed and executed by the processor 900. Examples of the storage unit 912 include but are not limited to a SIM, ROM, flash memory, RAM, hard-disk, and optical data storage device. The communication unit 920 may be a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 900. In an example, the communication unit 920 transmits and receives the signals via at least one antenna 922 shown in FIG. 9.

In an embodiment, the storage unit 910 and the program code 912 may be omitted. The processor 900 may include a storage unit with stored program code.

The processor 900 may implement any steps described in exemplified embodiments on the wireless network node 90, e.g., via executing the program code 912.

The communication unit 920 may be a transceiver. The communication unit 920 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless terminal (e.g. a user equipment or another wireless network node) .

FIG. 10 shows a flowchart of a method according to an embodiment of the present disclosure. The method shown in FIG. 10 may be used in a network function (e.g. the AF and/or the NEF and/or a wireless device comprising/performing the functionalities of the AF and/or the NEF) and comprises the following steps:

Step 1001: Transmit, to an MB-SMF, a session establishment request associated with an MBS session.

Step 1002: Receive an indication associated with an establishment of the MBS session.

Step 1003: Transmit, to a PCF, a session association request associated with the MBS session.

In FIG. 10, the network function transmits a session establishment request associated with an MBS session. After receiving an indication of associated with an establishment of the MBS session, the network function transmits a session association request associated with the MBS session, e.g., so as to build a signaling path between the network function and the MB-SMF through the PCF (i.e. via bonded/associated N5 session and N7 session) . That is, after step 1003, the network function may transmit subsequent signaling of the MBS session to the MB-SMF via the PCF.

In an embodiment, the establishment is associated with a policy association which is associated with the MBS session and/or is between the MB-SMF and the PCF (i.e. N7 session) .

In an embodiment, the indication is received in a session establishment response from the MB-SMF.

In an embodiment, the indication is received from a BSF. For example, the network function may subscribe a notification associated with the MBS session to the BSF. When or after receiving a register request associated with the MBS session (e.g. Nbsf_Management_register comprising PCF ID and MBS session ID) or binding the PCF and the MBS session, the BSF transmits the indication to the network function.

In an embodiment, the network function may transmit a discovery request (e.g. Nbsf_management_discovery comprising the MBS session ID) to the BSF (e.g. after receiving the indication) , to receive/acquire/acknowledge information of the PCF (e.g. PCF ID) associated with the MBS session.

In an embodiment, the information of the PCF is included in the indication.

FIG. 11 shows a flowchart of a method according to an embodiment of the present disclosure. The method shown in FIG. 11 may be used in an MB-SMF (e.g. a wireless device comprising/performing the functionalities of the MB-SMF) and comprises the following steps:

Step 1101: Receive, from a network function, a session establishment request associated with an MBS session.

Step 1102: Establish, with a PCF, a policy association associated with the MBS session.

Step 1103: Transmit, to the network function, an indication of an establishment of the policy association.

In FIG. 11, the MB-SMF receives a session establishment request associated with an MBS session from a network function (e.g. AF/NEF) and accordingly establishes a policy association associated with the MBS session with a PCF (i.e. N7 session) . After the policy association is established, the MB-SMF transmits an indication of the establishment of the policy association. After step 1103, a signaling path from the network function, through the PCF and to the MB-SMF may be built and the subsequent signaling of the MBS session may be transmitted through this signaling path (e.g. AF→NEF→PCF→MB-SMF) .

In an embodiment, the indication comprises information of the PCF (e.g. PCF ID) .

FIG. 12 shows a flowchart of a method according to an embodiment of the present disclosure. The method shown in FIG. 12 may be used in BSF (e.g. a wireless device comprising/performing the functionalities of the BSF) and comprises the following steps:

Step 1201: Receive, from a PCF, a register request associated with an MBS session and the PCF.

Step 1202: Transmit, to a network function, an indication associated with an establishment of the MBS session.

In FIG. 12, the BSF receives a register request associated with an MBS session and a PCF from the PCF. The BSF may transmit an indication associated with an establishment of the MBS session to a network function (e.g. AF/NEF) after receiving the register request associated with an MBS session and the PCF from the PCF and/or binding the MBS session and the PCF.

In an embodiment, the establishment is associated with a policy association which is associated with the MBS session and/or between the PCF and an MB-SMF (e.g. N7 session) .

In an embodiment, the BSF may receive a subscription request associated with the MBS session from the network function. That is, the network function may subscribe a notification associated with the MBS session to the BSF.

In an embodiment, the BSF may receive a discovery request associated with the MBS session (e.g. comprising the MBS session ID) from the network function. Based on the discovery request, the BSF transmit information of the PCF (e.g. PCF ID) to the network function.

In an embodiment, information of the PCF (e.g. PCF ID) is included in the indication.

While various embodiments of the present disclosure have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Likewise, the various diagrams may depict an example architectural or configuration, which are provided to enable persons of ordinary skill in the art to understand exemplary features and functions of the present disclosure. Such persons would understand, however, that the present disclosure is not restricted to the illustrated example architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, as would be understood by persons of ordinary skill in the art, one or more features of one embodiment can be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any one of the above-described exemplary embodiments.

It is also understood that any reference to an element herein using a designation such as "first, " "second, " and so forth does not generally limit the quantity or order of those elements. Rather, these designations can be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not mean that only two elements can be employed, or that the first element must precede the second element in some manner.

Additionally, a person having ordinary skill in the art would understand that information and signals can be represented using any one of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits and symbols, for example, which may be referenced in the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

A skilled person would further appreciate that any one of the various illustrative logical blocks, units, processors, means, circuits, methods and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two) , firmware, various forms of program or design code incorporating instructions (which can be referred to herein, for convenience, as "software" or a "software unit” ) , or any combination of these techniques.

To clearly illustrate this interchangeability of hardware, firmware and software, various illustrative components, blocks, units, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware or software, or a combination of these techniques, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in various ways for each particular application, but such implementation decisions do not cause a departure from the scope of the present disclosure. In accordance with various embodiments, a processor, device, component, circuit, structure, machine, unit, etc. can be configured to perform one or more of the functions described herein. The term “configured to” or “configured for” as used herein with respect to a specified operation or function refers to a processor, device, component, circuit, structure, machine, unit, etc. that is physically constructed, programmed and/or arranged to perform the specified operation or function.

Furthermore, a skilled person would understand that various illustrative logical blocks, units, devices, components and circuits described herein can be implemented within or performed by an integrated circuit (IC) that can include a general purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device, or any combination thereof. The logical blocks, units, and circuits can further include antennas and/or transceivers to communicate with various components within the network or within the device. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other suitable configuration to perform the functions described herein. If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium. Thus, the steps of a method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium.

Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program or code from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

In this document, the term "unit" as used herein, refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purpose of discussion, the various units are described as discrete units; however, as would be apparent to one of ordinary skill in the art, two or more units may be combined to form a single unit that performs the associated functions according embodiments of the present disclosure.

Additionally, memory or other storage, as well as communication components, may be employed in embodiments of the present disclosure. It will be appreciated that, for clarity purposes, the above description has described embodiments of the present disclosure with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units, processing logic elements or domains may be used without detracting from the present disclosure. For example, functionality illustrated to be performed by separate processing logic elements, or controllers, may be performed by the same processing logic element, or controller. Hence, references to specific functional units are only references to a suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.

Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as recited in the claims below.

Claims

A wireless communication method for use in a network function, the method comprising:

transmitting, to a multicast broadcast session management function, a session establishment request associated with a multicast broadcast service, MBS, session,

receiving an indication associated with an establishment of the MBS session, and

transmitting, to a policy control function, a session association request associated with the MBS session.
The wireless communication method of claim 1, wherein the establishment is associated with a policy association which is associated with the MBS session.
The wireless communication method of claim 1 or 2, wherein the establishment is associated with a policy association between the multicast broadcast session management function and the policy control function.
The wireless communication method of any of claims 1 to 3, wherein the indication is received in a session establishment response from the multicast broadcast session management function.
The wireless communication method of any of claims 1 to 3, wherein the indication is received from a binding support function.
The wireless communication method of claim 5, further comprising:

transmitting, to the binding support function, a subscription request associated with the MBS session.
The wireless communication method of any of claims 1 to 6, further comprising:

transmitting, to a binding support function, a discovery request associated with the MBS session, and

retrieving, from the binding support function, information of the policy control function.
The wireless communication method of any of claims 1 to 6, wherein the indication comprises information of the policy control function.
The wireless communication method of any of claims 1 to 8, further comprising:

transmitting, to the multicast broadcast session management function, a request associated with the MBS session by transmitting the request to the policy control function.
The wireless communication method of any of claims 1 to 9, wherein the network function comprises at least one of an application function or a network exposure function.
A wireless communication method for use in a multicast broadcast session management function, the method comprising:

receiving, from a network function, a session establishment request associated with a multicast broadcast service, MBS, session,

establishing, with a policy control function, a policy association associated with the MBS session, and

transmitting, to the network function, an indication of an establishment of the policy association.
The wireless communication method of claim 11, wherein the indication comprises information of the policy control function.
The wireless communication method of claim 11 or 12, further comprising:

receiving, from the policy control function, a request associated with the MBS session.
The wireless communication method of any of claims 11 to 13, wherein the network function comprises at least one of an application function or a network exposure function.
A wireless communication method for use in a binding support function, the method comprising:

receiving, from a policy control function, a register request associated with a multicast broadcast service, MBS, session and the policy control function, and

transmitting, to a network function, an indication associated with an establishment of the MBS session.
The wireless communication method of claim 15, wherein the establishment is associated with a policy association which is associated with the MBS session.
The wireless communication method of claim 15 or 16, wherein the establishment is associated with a policy associated between the multicast broadcast session management function and a policy control function.
The wireless communication method of any of claims 15 to 17, further comprising:

receiving, from the network function, a subscription request associated with the MBS session.
The wireless communication method of any of claims 15 to 18, further comprising:

receiving, from the network function, a discovery request associated with the MBS session, and

transmitting, to the network function, information associated with the policy control function.
The wireless communication method of any of claims 15 to 18, wherein the indication comprises information of the policy control function.
The wireless communication method of any of claims 15 to 20, wherein the network function comprises at least one of an application function or a network exposure function.
A wireless device comprising a network function, the wireless device comprising:

a communication unit, configured to:

transmit, to a multicast broadcast session management function, a session establishment request associated with a multicast broadcast service, MBS, session,

receive an indication associated with an establishment of the MBS session, and

transmit, to a policy control function, a session association request associated with the MBS session.
The wireless device of claim 22, further comprising a processor configured to perform a wireless communication method of any one of claims 2 to 10.
A wireless device comprising a multicast broadcast session management function, the wireless device comprising:

a communication unit, configured to receive, from a network function, a session establishment request associated with a multicast broadcast service, MBS, session, and

a processor, configured to establish, with a policy control function, a policy association associated with the MBS session, and

wherein the communication unit is further configured to transmit, to the network function, an indication of an establishment of the policy association.
The wireless device of claim 24, wherein the processor is further configured to perform a wireless communication method of any one of claims 12 to 14.
A wireless device comprising a binding support function, the wireless device comprising:

a communication unit, configured to:

receive, from a policy control function, a register request associated with a multicast broadcast service, MBS, session and the policy control function, and

transmit, to a network function, an indication associated with an establishment of the MBS session.
The wireless device of claim 26, further comprising a processor configured to perform a wireless communication method of any one of claims 16 to 21.
A computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement a wireless communication method recited in any one of claims 1 to 21.