CN112368976A

CN112368976A - Terminal and method for performing group communication

Info

Publication number: CN112368976A
Application number: CN201980045332.2A
Authority: CN
Inventors: ***
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2019-02-19
Filing date: 2019-02-19
Publication date: 2021-02-12
Anticipated expiration: 2039-02-19
Also published as: WO2020168467A1; CN112368976B

Abstract

A terminal and method for performing group communication are provided. The method for performing group communication of terminals includes: performing group communication of a group by communicating with a first terminal using an interface; and processing the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal.

Description

Terminal and method for performing group communication

Technical Field

The present disclosure relates to the field of communication systems, and more particularly, to a terminal and method for performing group communication.

Background

In Long Term Evolution (LTE) and New Radio (NR) systems, public network systems, such as Public Land Mobile Network (PLMN) based public land networks, are commonly deployed. However, in some scenarios, such as offices, homes, and factories, local users or administrators often deploy local networks for more efficient and secure management. The members of the local network group may communicate in a point-to-point manner or in a point-to-multipoint communication. Furthermore, the prior art does not support group communication for members of a local network group within a 5G system.

Therefore, a terminal and method for performing group communication are needed.

Disclosure of Invention

An object of the present disclosure is to propose a terminal and method for performing group communication, which can provide good group communication performance and high reliability, and provide a solution how to transmit user data within a 5G system and corresponding control information and/or procedures.

In a first aspect of the present disclosure, a terminal in group communication includes: a memory; a transceiver; and a processor coupled to the memory and the transceiver. The processor is configured to: performing group communication of a group by communicating with a first terminal using an interface; and processing the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal.

In a second aspect of the present disclosure, a method for performing group communication of terminals includes: performing group communication of a group by communicating with a first terminal using an interface; and processing the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal.

In a third aspect of the disclosure, a non-transitory machine-readable storage medium has stored thereon instructions which, when executed by a computer, cause the computer to perform the above-described method.

In a fourth aspect of the present disclosure, a terminal device includes: a processor; and a memory for storing the computer program. The processor is configured to execute the computer program stored in the memory to perform the above-described method.

Drawings

In order to more clearly explain embodiments of the present disclosure or related art, the following drawings, which will be described in the embodiments, are briefly introduced. It is evident that these drawings are only some embodiments of the disclosure and that a person skilled in the art can derive other drawings from them without inventive effort.

Fig. 1 is a block diagram of a user equipment and a terminal performing group communication according to an embodiment of the present disclosure.

Fig. 2 is a flowchart illustrating a method for performing group communication of terminals according to an embodiment of the present disclosure.

Fig. 3 is a schematic diagram illustrating AN Access Network (AN) release procedure according to AN embodiment of the present disclosure.

Fig. 4 is a schematic diagram of an exemplary illustration of a point-to-multipoint communication user plane topology according to an embodiment of the disclosure.

Fig. 5 is a diagram of an exemplary illustration of a point-to-multipoint communication group Protocol Data Unit (PDU) session according to an embodiment of the present disclosure.

Fig. 6 is a block diagram of a system for wireless communication in accordance with an embodiment of the present disclosure.

Detailed Description

The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings, taking technical contents, structural features, achieving objects, and effects. In particular, the terminology used in the embodiments of the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure.

Fig. 1 illustrates that in some embodiments, a User Equipment (UE) 10 and a terminal 20 are provided that perform group communication in accordance with embodiments of the present disclosure. The UE 10 may include a processor 11, a memory 12, and a transceiver 13. The terminal 20, such as a network node, may comprise a processor 21, a memory 22 and a transceiver 23. The

processor

11 or 21 may be used to implement the proposed functions, procedures and/or methods described in this specification. Layers of the radio interface protocol may be implemented in the

processor

11 or 21. The memory 12 or 22 is operatively coupled with the

processor

11 or 21 and stores various information to operate the

processor

11 or 21. The

transceiver

13 or 23 is operatively coupled with the

processor

11 or 21, and the

transceiver

13 or 23 transmits and/or receives wireless signals.

The

processor

11 or 21 may comprise an application-specific integrated circuit (ASIC), other chipset, logic circuit and/or data processing device. The memory 12 or 22 may include read-only memory (ROM), Random Access Memory (RAM), flash memory, memory cards, storage media, and/or other storage devices. The

transceiver

13 or 23 may include a baseband circuit to process radio frequency signals. When an embodiment is implemented in software, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The modules may be stored in the memory 12 or 22 and executed by the

processor

11 or 21. The memory 12 or 22 may be implemented within the

processor

11 or 21 or external to the

processor

11 or 21, where those memories are known in the art to be communicatively coupled to the

processor

11 or 21 via various means.

According to the sidechain technology developed under 3rd generation partnership project (3GPP) releases 14, 15 and beyond, communication between UEs involves vehicle-to-ambient (V2X) communication, which includes vehicle-to-vehicle (V2V), vehicle-to-pedestrian (V2P) and vehicle-to-infrastructure/network (V2 to 2I/N). The UEs communicate directly with each other through a side-chain interface such as the PC5 interface. Communication between the UE and a terminal, such as a network node, is in accordance with third generation partnership project (3GPP) new air interface (NR) releases 14, 15 and beyond.

Some embodiments of the present disclosure propose a terminal and method for performing group communication, which can provide good group communication performance and high reliability, and can provide a solution how to transmit user data within a 5G system and corresponding control information and/or procedures. In addition, uplink (DL) and/or Downlink (DL) traffic of 5G Local Area Network (LAN) communications is forwarded between User Plane Functions (UPFs), such as protocol data unit session anchors (PSA) UPFs, of different Protocol Data Unit (PDU) sessions, through Nx. For example, Nx is a shared user plane tunnel based interface that connects PSA UPFs of a single 5G LAN group.

In some embodiments, the processor 21 is configured to perform group communication of a group by communicating with a first terminal using an interface, and to process the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal.

In some embodiments, the processor 21 is configured to initiate AN Access Network (AN) release. In some embodiments, the processor 21 initiating the AN release further comprises: the processor 21 decides to release the interface if the interface is used and all resources of the first terminal for the group communication termination of the group are released. In some embodiments, the processor 21 initiating the AN release further comprises: the interface and its associated tunnel are reserved with the group. In some embodiments, when creating the group, the terminal configures the interface and associated tunnels for the interface and selects the first terminal to serve the group according to group information for the group. In some embodiments, when the group is dismissed, the interface and its associated tunnel are released. In some embodiments, the terminal is a Session Management Function (SMF), the first terminal is a User Plane Function (UPF), the set of communications is a Protocol Data Unit (PDU) session, and the interface is an Nx interface. In some embodiments, the processor 21 initiating the AN release further comprises: if there is AN acknowledged (R) AN condition or (R) AN internal cause, the (R) AN decides to initiate a User Equipment (UE) context release in the (R) AN.

In some embodiments, when the (R) AN initiates a UE context release in the (R) AN, the (R) AN sends a UE context release request message to AN access and mobility management function (AMF). In some embodiments, the UE context release request message includes a PDU session Identification (ID) list indicating a plurality of PDU sessions served by the (R) AN of the UE. In some embodiments, the AMF sends a UE context release command to the (R) AN if the AMF receives the UE context release request message, or because the internal AMF event includes receiving a service request or a registration request for establishing a non-access stratum (NAS) signaling connection through a next generation RAN (NextGen RAN, NG RAN). In some embodiments, if the AMF receives the service request or registration request for establishing NAS signaling connection through the NG RAN, the AMF releases the old NAS signaling connection and continues the service request or registration request procedure after successfully authenticating the UE. In some embodiments, if the (R) AN connection with the UE is not released: a) the (R) AN requesting the UE to release the (R) AN connection, and the (R) AN deleting the context of the UE upon receiving AN (R) AN connection release confirmation from the UE; or b) if the UE context release order indicates that the UE has locally released a Radio Resource Control (RRC) connection, the (R) AN locally releases the RRC connection.

In some embodiments, the (R) AN acknowledges the UE context release order by returning a UE context release complete message to the AMF, and the signaling connection for the UE between the AMF and the (R) AN is released. In some embodiments, the AMF invokes a request to the SMF including a PDU session ID, PDU session deactivation, cause, operation type, user location information, location information age (SM) information, and/or Session Management (SM) information for each group communication in the UE context release completion. In some embodiments, the SMF initiates a session modification request to the UPF indicating a need to un-tunnel information for AN, a UPF terminating the N3 interface, or a UPF terminating the Nx interface. In some embodiments, the UPF initiates a session modification response to the SMF, which acknowledges the session modification request from the SMF. In some embodiments, for each group communication in the UE context release completion, the SMF invokes a response to the AMF acknowledging the request including the PDU session ID, the PDU session deactivation, the cause, the operation type, the user location information, the location information age, and/or the Session Management (SM) information.

In some embodiments, the processor 21 is configured to initiate a PDU session release. In some embodiments, the processor 21 initiating the PDU session release further comprises: when the group communication terminating the first terminal is released, the first terminal, the interface and the associated tunnel of the interface are retained. In some embodiments, the processor 21 initiating the PDU session release further comprises: the first terminal, the interface and the associated tunnel with the interface are retained when all group communications terminating the group of the first terminal are released. In some embodiments, the processor 21 initiating the PDU session release further comprises: when all group communications of the group are released or the group is released, the first terminal, the interface and the associated tunnel of the interface are released. In some embodiments, the processor 21 initiating the PDU session release further comprises: when all group communications terminating the group of the first terminal are released, the first terminal is released and/or the interface and its associated tunnel are released. In some embodiments, the first terminal is a UPF, the set of communications is a PDU session, and the interface is an Nx interface. In some embodiments, the processor 21 initiating the PDU session release further comprises: releasing all resources associated with the PDU session, including an Internet Protocol (IP) address and/or prefix assigned to the IP-based PDU session and/or UPF resources used by the PDU session.

Fig. 2 illustrates a method 200 for performing group communication of terminals according to an embodiment of the disclosure. The method 200 comprises the following steps: at block 202, performing group communication of a group by communicating with a first terminal using an interface; and processing the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal at block 204.

In some embodiments, method 200 further comprises initiating AN Access Network (AN) release. In some embodiments, the method 200 initiating the AN release further comprises: if the interface is used and all resources of the first terminal for the group communication termination of the group are released, the method 200 decides to release the interface. In some embodiments, the method 200 initiating the AN release further comprises: the interface and its associated tunnel are reserved with the group. In some embodiments, when creating the group, the terminal configures the interface and associated tunnels for the interface and selects the first terminal to serve the group according to group information for the group. In some embodiments, when the group is dismissed, the interface and its associated tunnel are released. In some embodiments, the terminal is a Session Management Function (SMF), the first terminal is a User Plane Function (UPF), the set of communications is a Protocol Data Unit (PDU) session, and the interface is an Nx interface. In some embodiments, the method 200 of initiating the AN release further comprises: if there is AN acknowledged (R) AN condition or (R) AN internal cause, the (R) AN decides to initiate a User Equipment (UE) context release in the (R) AN.

In some embodiments, when the (R) AN initiates a UE context release in the (R) AN, the (R) AN sends a UE context release request message to AN access and mobility management function (AMF). In some embodiments, the UE context release request message includes a PDU session Identification (ID) list indicating a plurality of PDU sessions served by the (R) AN of the UE. In some embodiments, the AMF sends a UE context release command to the (R) AN if the AMF receives the UE context release request message, or because the internal AMF event comprises receiving a service request or a registration request for establishing a non-access stratum (NAS) signaling connection through a next generation ran (ng ran). In some embodiments, if the AMF receives the service request or registration request for establishing NAS signaling connection through the NG RAN, the AMF releases the old NAS signaling connection and continues the service request or registration request procedure after successfully authenticating the UE. In some embodiments, if the (R) AN connection with the UE is not released: a) the (R) AN requesting the UE to release the (R) AN connection, and the (R) AN deleting the context of the UE upon receiving AN (R) AN connection release confirmation from the UE; or b) if the UE context release order indicates that the UE has locally released a Radio Resource Control (RRC) connection, the (R) AN locally releases the RRC connection.

In some embodiments, the (R) AN acknowledges the UE context release order by returning a UE context release complete message to the AMF, and the signaling connection for the UE between the AMF and the (R) AN is released. In some embodiments, the AMF invokes a request to the SMF including a PDU session ID, PDU session deactivation, cause, operation type, user location information, location information age, and/or Session Management (SM) information for each group communication in the UE context release completion. In some embodiments, the SMF initiates a session modification request to the UPF indicating a need to un-tunnel information for AN, a UPF terminating the N3 interface, or a UPF terminating the Nx interface. In some embodiments, the UPF initiates a session modification response to the SMF, which acknowledges the session modification request from the SMF. In some embodiments, for each group communication in the UE context release completion, the SMF invokes a response to the AMF acknowledging the request including the PDU session ID, the PDU session deactivation, the cause, the operation type, the user location information, the location information age, and/or the Session Management (SM) information.

In some embodiments, the method 200 further comprises: initiating a PDU session release. In some embodiments, the method 200 initiating the PDU session release further comprises: when the group communication terminating the first terminal is released, the first terminal, the interface and the associated tunnel of the interface are retained. In some embodiments, the method 200 initiating the PDU session release further comprises: the first terminal, the interface and the associated tunnel with the interface are retained when all group communications terminating the group of the first terminal are released. In some embodiments, the method 200 initiating the PDU session release further comprises: when all group communications of the group are released or the group is released, the first terminal, the interface and the associated tunnel of the interface are released. In some embodiments, the method 200 initiating the PDU session release further comprises: when all group communications terminating the group of the first terminal are released, the first terminal is released and/or the interface and its associated tunnel are released. In some embodiments, the first terminal is a UPF, the set of communications is a PDU session, and the interface is an Nx interface. In some embodiments, the method 200 initiating the PDU session release further comprises: releasing all resources associated with the PDU session, including an Internet Protocol (IP) address and/or prefix assigned to the IP-based PDU session and/or UPF resources used by the PDU session.

Fig. 3 illustrates that in some embodiments, AN Access Network (AN) release procedure is provided in accordance with embodiments of the present disclosure. In some embodiments, AN release procedure is used to release the logical NG Access Point (AP) signaling connection and associated N3 user plane connection and (R) AN RRC signaling and resources. When the NG-AP signaling connection is lost due to (R) AN or AMF failure, AN release is performed locally by the AMF330 or (R) AN320, as described in the process flow below, without using or relying on any of the signaling shown between the (R) AN320 and the AMF 330. This AN release results in all UP connections of the UE 310 being deactivated.

In some embodiments, the initiation of AN release may be due to: (R) the AN is initiated for reasons such as, for example, O & M intervention, unspecified failure, (R) AN (e.g., wireless) link failure, user inactivity, inter-system redirection, request to establish quality of experience (QoS) flows for IP Multimedia Subsystem (IMS) voice, release due to UE-generated signaling connection release, mobility restrictions, etc.; or the AMF is initiated for reasons such as unspecified faults, etc.

In some embodiments, AN (R) AN-initiated and AMF-initiated AN release procedure is shown in fig. 3. For this procedure, the affected SMF350 and UPF 340 are both under control of the Public Land Mobile Network (PLMN) serving the UE 310, e.g., in a home routed roaming scenario, the SMF350 and UPF 340 in the Home Public Land Mobile Network (HPLMN) are not involved.

In some embodiments, in steps 1a and 1b, the (R) AN320 may decide to initiate a UE context release in the (R) AN320 if there are some confirmed (R) AN conditions (e.g., radio link failure) or for other (R) AN internal reasons. In this case, (R) AN320 sends AN N2 UE context release request (cause, PDU session ID list with active N3 user plane) to AMF 330. The reason indicates the reason for the release (e.g., AN link failure, O & M intervention, unspecified failure, etc.). The PDU session ID list indicates the PDU sessions served by the (R) AN320 of the UE 310. Steps 1a and 1b are described in TS 38.413 section 8.3.2 "UE context release request (gNB initiated)".

In some embodiments, in step 2, the AMF330 to (R) AN 320: if the AMF330 receives the N2 UE context release request message, or due to AN internal AMF event including the reception of a service request or a registration request for still establishing another NAS signaling connection through the NG-RAN, the AMF330 sends AN N2 UE context release command to the (R) AN320 (cause). The reason indicates the reason from the (R) AN320 or the reason caused by the AMF event in steps 1a and 1 b. In case (R) AN320 is NG-RAN, step 2 is detailed in TS 38.413 section 8.3.3 "UE context release (AMF initiated)". In the case where (R) AN320 is N3IWF, step 2 is described in section 4.12. In some embodiments, if the AMF330 receives a service request or registration request to still establish another NAS signaling connection through the NG-RAN, after successfully authenticating the UE 310, the AMF330 releases the old NAS signaling connection and then continues the service request or registration request procedure.

In some embodiments, in step 3 (conditional), if the (R) AN connection (e.g., RRC connection or NWu connection) with the UE 310 has not been released (step 1a), then: (a) (R) the AN320 requesting the UE 310 to release the (R) AN connection, after receiving AN (R) AN connection release acknowledgement from the UE 310, (R) the AN320 deleting the context of the UE; or b) if the cause in the N2 UE context release order indicates that the UE 310 has locally released the RRC connection, (R) the AN320 locally releases the RRC connection.

In some embodiments, in step 4, (R) AN320 acknowledges the N2 release by returning AN N2 UE context release complete (PDU session ID list with active N3 user plane, UE radio capability, user location information, location information age) message to AMF 330. The PDU session ID list indicates the PDU sessions served by the (R) AN320 of the UE 310. The AMF330 always stores the latest UE radio capability information received from the NG-RAN node. The N2 signaling connection between the AMF330 and the (R) AN320 for the UE 310 is released. The (R) AN320 provides a list of recommended cell/TA/NG-RAN node identifiers for paging to the AMF 330. In some embodiments, the NG-RAN node may provide RAN usage data reporting if the PLMN has configured secondary RAT usage reporting. In some embodiments, for example, in case the UE 310 does not acknowledge the RRC connection release, step 4 may be performed immediately after step 2, i.e. it cannot be delayed.

In some embodiments, in step 5 (conditional), AMF330 to SMF 350: for each PDU session in the N2 UE context release complete, AMF330 invokes a Nsmf _ PDU session ID, PDU session deactivation, cause, operation type, user location information, location information age, N2 SM information (secondary radio access technology, RAT) usage data, the cause in step 5 is the same as in step 2, if step 1b contains a PDU session ID list with active N3 user plane, steps 5 to 7 are performed before step 2.

In some embodiments, in step 6a (conditional), SMF350 to UPF 340: n4 session modify request (unblock AN or N3 or Nx UPF tunnel information, open/close buffering). In some embodiments, in step 6a, SMF350 initiates a N4 session modification procedure indicating a need to un-terminate the tunnel information of the AN or UPF of N3. The on/off buffer indicates whether the UPF 340 can buffer incoming DL PDUs. In some embodiments, if multiple UPFs are used in a PDU session and the SMF350 determines to release the UPF terminating N3, step 6a is performed for the UPF (e.g., PSA) terminating N9, for the current N3 UPF. The SMF350 then releases the N4 session to the N3 UPF (N4 release is not shown on the call flow). In some embodiments, option 1: in the 5G-LAN, if the Nx interface is used and all resources for terminating the PDU session of the PSA UPF of the corresponding group are released, the SMF350 determines to additionally release the PSA UPF terminating the Nx. In some embodiments, option 2: the Nx interface and associated tunnels remain with the group at all times. This means that when creating a group, the SMF350 configures an Nx interface and a Core Network (CN) tunnel for the interface based on the group information, and the SMF350 selects a UPF serving the group based on the group information. When the group is released, the Nx interface and the tunnel are released. In some embodiments, if the cause of AN release is due to user inactivity or UE redirection, SMF350 may reserve a Guaranteed Bit Rate (GBR) QoS flow. Otherwise, after the AN release procedure is complete, SMF350 may trigger a PDU session modification procedure for the GBR QoS flow of UE 310.

In some embodiments, in step 6b (conditional), UPF 340 to SMF 350: the N4 session modify response acknowledges the SMF request. In some embodiments, in step 7 (conditional), SMF350 to AMF 330: an Nsmf pdusesion _ UpdateSMContext response to step 5. After completing the process, the AMF330 considers N2 and N3 as released and enters a CM-IDLE state.

In some embodiments, a PDU session release is provided. The PDU session release procedure is used to release all resources associated with a PDU session, including: the IP address/prefix allocated for IP based PDU sessions, which in the case of multihoming may include the release of multiple prefixes (as defined in TS 23.501), i.e. any UPF resources (including N3/N9/termination) used by the PDU session. In some embodiments, for a 5G-LAN, in option 1: when the PDU session terminating the PSA UPF is released, the PSA UPF, terminating Nx interface and tunnel are retained. In some embodiments, the PSA UPF, terminating Nx interface, and tunnel are preserved when all PDU sessions terminating the PSA UPF are released. In some embodiments, when all PDU sessions of a group are released or the group is torn down, the associated PSA UPF, Nx interface, and tunnel are released. Optionally, in some embodiments, in option 2: when all PDU sessions terminating the PSA UPF are released, the PSA UPF is released and/or terminating Nx interfaces and tunnels are released.

Fig. 4 and 5 illustrate that, in some embodiments, point-to-multipoint group communication is provided. In some embodiments, to support one-to-many communication in a group, a group specific packet data network (PDU) session is introduced. Fifth generation systems (5GS) may support group specific PDU session establishment, release, modification, and group/group member addition or deletion. It should be appreciated that Session Management Function (SMF) node 108 is responsible for group-specific PDU session management. Different members of the group may be served by the same User Plane Function (UPF) node (e.g., UPF1 node 106) or different UPF nodes (e.g., UPF1 node 106 and UPF2 node 112). In one group, the scenarios may be illustrated in fig. 4 and 5. UE-T102 is the sender UE and UE-R1104 and UE-R2110 are the receiver UEs, where UE-T102 and UE-R1104 are served by the same UPF1 node 106 and UE-R2110 is served by UPF2 node 112. Data from the UE-T102 is sent in the fifth generation system (5GS) and routed by UPF nodes, such as UPF1 node 106 and UPF2 node 112.

The group specific PDU session terminates at the member and serving UPF. When a group is established by an Application Function (AF) or a UE, a group-specific PDU session will be established for each group member added to the group through group creation. SMF node 108 is enhanced to support group-based PDU session management functions, including group-based PDU session establishment. After the group is created, when a group member is added to the group, a group specific PDU session will be established for the newly joined member. SMF node 108 is responsible for establishing a routing tunnel between the UPF node serving the newly joined member and the UPF node serving the authorized sending member.

In some embodiments, the process describes a one-to-many communication PDU session establishment procedure. It is understood that a group is managed by the same SMF. The group creation and group member joining process is based on other solutions and is not mentioned in this solution. The present embodiment is an example, and the present disclosure is not limited thereto.

When a group is created, the group members UE-T102 and UE-R1104 are added to the group and UE-T102 is authorized to send one-to-many data to the members in the group. UE-T102 initiates a group specific PDU session setup request including a request for S-NSSAI, group information, etc. Specifically, the group information may be, for example, a group index, group-specific Data Network Name (DNN) information, or group-specific application server information.

Upon receiving the request from UE-T102, SMF node 108 selects UPF1 node 106 as the serving UPF for the particular group based on the S-NSSAI information and the group information. The SMF node 108 sends a session setup request to the UPF1 node 106, including the assigned Core Network (CN) tunnel information for the N3 interface. The UPF1 node 106 acknowledges by sending a session setup response message. SMF node 108 sends a PDU session acceptance to UE-T102. In the case where the PDU session type is IPv4 or IPv6 or IPv4v6, the SMF node 108 assigns an IP address/prefix for the PDU session, and the address/prefix is for a specific group. Optionally, if the group shares the PDU session with other groups, the group-specific address is also assigned to at least one UE in the other groups.

When the UE-R2110 is added to the group, the UE-R2110 initiates a PDU session setup request to the SMF node 108, including S-NSSAI information and group information. The SMF node 108 selects the UPF2 node 112 as the serving UPF for the UE-R2110 and determines to establish a routing tunnel between the UPF1 node 106 serving the UE-T102 and the UPF2 node 112. SMF node 108 sends a session establishment request to UPF2 node 112, including the assigned CN tunnel information; the CN tunnel information includes the UPF2 address of the tunnel between the UPF1 node 106 and the UPF2 node 112 and the UPF2 address of the N3 tunnel. The UPF2 node 112 acknowledges by sending a session setup response message. The SMF node 108 establishes a routing tunnel between the UPF1 node 106 and the UPF2 node 112 and provides the UPF2 address of the tunnel between the UPF1 node 106 and the UPF2 node 112 to the UPF1 node 106. In addition, SMF node 108 provides association information for the routing tunnel and the PDU session for UE-T102. The SMF node 108 sends a PDU session acceptance to the UE-R2110. In the case where the PDU session type is IPv4 or IPv6 or IPv4v6, the SMF node 108 assigns an IP address/prefix for the PDU session, which is specific to the group of UE-R2110. If there is an existing PDU session for another group of UE-R2110, the existing PDU session may be reused for the newly joined group, i.e., multiple groups may share one PDU session for receiving members in the group.

In addition, the UE-T102 sends the group data to the UPF1 node 106, and the UPF1 node determines to receive the UE-R1104 and the UE-R2110 according to the routing association information provided at block 8, and routes the data to the tunnels corresponding to the UE-R1104 and the UE-R2110, respectively. If the PDU session is shared by multiple groups, the UPF1 node 106 determines from the group specific address information to receive the UE-R1104, UE-R2110 for group information.

Fig. 6 is a block diagram of an example system 700 for wireless communication in accordance with an embodiment of the present disclosure. The embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. Fig. 6 shows a system 700 that includes a Radio Frequency (RF) circuit 710, a baseband circuit 720, an application circuit 730, a memory/storage device 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled to each other at least as shown.

The application circuitry 730 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may include any combination of general purpose processors and special purpose processors, such as a graphics processor and an application processor. A processor may be coupled to the memory/storage and configured to execute instructions stored in the memory/storage to cause various applications and/or operating systems to run on the system.

Baseband circuitry 720 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor may comprise a baseband processor. The baseband circuitry may handle various wireless control functions that may enable communication with one or more wireless networks through the RF circuitry. The wireless control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, and the like. In some embodiments, the baseband circuitry may provide communications compatible with one or more wireless technologies. For example, in some embodiments, the baseband circuitry may support communication with an Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or other Wireless Metropolitan Area Networks (WMANs), Wireless Local Area Networks (WLANs), Wireless Personal Area Networks (WPANs). Embodiments in which baseband circuitry is used for wireless communications supporting more than one wireless protocol may be referred to as multi-mode baseband circuitry.

In various embodiments, baseband circuitry 720 may include circuitry for operating signals that are strictly considered not to be in baseband frequencies. For example, in some embodiments, the baseband circuitry may include circuitry for operating on a signal having an intermediate frequency that is between the baseband frequency and the radio frequency.

RF circuitry 710 may enable communication with a wireless network using electromagnetic radiation modulated by a non-solid medium. In various embodiments, the RF circuitry may include switches, filters, amplifiers, and the like to facilitate communication with the wireless network.

In various embodiments, RF circuitry 710 may include circuitry for operating signals that are not considered strictly at radio frequencies. For example, in some embodiments, the RF circuitry may include circuitry for operating on signals having an intermediate frequency that is between a baseband frequency and a radio frequency.

In various embodiments, the transmit circuitry, control circuitry, or receive circuitry discussed above with respect to the user equipment, eNB, or gNB may be embodied in whole or in part in one or more of RF circuitry, baseband circuitry, and/or application circuitry. As used herein, "circuitry" may refer to being part of or including the following components: an Application Specific Integrated Circuit (ASIC), an electronic Circuit, a processor (shared, dedicated, or group) and/or memory (shared, dedicated, or group), a combinational logic Circuit, and/or other suitable hardware components that provide the described functionality, which execute one or more software or firmware programs. In some embodiments, the electronic device circuitry may be implemented in, or functions associated with, one or more software or firmware modules.

In some embodiments, some or all of the components of the baseband circuitry, application circuitry, and/or memory/storage devices may be implemented together on a system on a chip (SOC).

Memory/storage 740 may be used to load and store data and/or instructions, for example, for a system. The memory/storage of one embodiment may comprise any combination of suitable volatile memory (e.g., Dynamic Random Access Memory (DRAM)) and/or non-volatile memory (e.g., flash memory).

In various embodiments, I/O interface 780 may include one or more user interfaces designed to enable a user to interact with the system and/or peripheral component interfaces designed to enable peripheral components to interact with the system. The user interface may include, but is not limited to, a physical keyboard or keypad, a touch pad, a speaker, a microphone, and the like. The peripheral component interfaces may include, but are not limited to, a non-volatile memory port, a Universal Serial Bus (USB) port, an audio jack, and a power interface.

In various embodiments, the sensor 770 may include one or more sensing devices to determine environmental conditions and/or location information related to the system. In some embodiments, the sensors may include, but are not limited to, a gyroscope sensor, an accelerometer, a proximity sensor, an ambient light sensor, and a positioning unit. The positioning unit may also be part of or interact with baseband circuitry and/or RF circuitry to communicate with components of a positioning network, such as Global Positioning System (GPS) satellites.

In various embodiments, display 750 may include displays such as liquid crystal displays and touch screen displays. In various embodiments, system 700 may be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a notebook, an ultrabook, a smartphone, and the like. In various embodiments, the system may have more or fewer components and/or different architectures. Where appropriate, the methods described herein may be implemented as a computer program. The computer program may be stored on a storage medium such as a non-transitory storage medium.

In the disclosed embodiments, a terminal and method for performing group communication are provided, which can provide good group communication performance and high reliability, and provide a solution how to transmit user data within a 5G system and corresponding control information and/or procedures. The disclosed embodiments are a combination of techniques/processes that may be employed in 3GPP specifications to create an end product.

One of ordinary skill in the art would understand that each of the elements, algorithms, and steps described and disclosed in the embodiments of the present disclosure may be implemented using electronic hardware or a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the application conditions and design requirements of the solution.

Those of ordinary skill in the art may implement the functionality of each particular application in different ways without departing from the scope of the present disclosure. It will be appreciated by those skilled in the art that reference may be made to the operation of the systems, devices and units described in the above embodiments because the operation of the systems, devices and units described above is substantially the same. For convenience and simplicity, these operations will not be described in detail.

It should be understood that the systems, devices, and methods disclosed in embodiments of the present disclosure may be implemented in other ways. The above embodiments are merely exemplary. The cell division is made based on logic functions only, and there is another division when it is implemented. Multiple units or components may be combined or may be integrated into another system. In addition, some features may be omitted, or not implemented. On the other hand, the shown or discussed mutual coupling, direct coupling or communication coupling may be operated through some ports, devices or units, and operated in an indirect or communication manner through electrical, mechanical or other forms.

Elements described as separate components may or may not be physically separate. The elements shown are or are not physical elements, i.e. may be located in one place or distributed over a plurality of network elements. Depending on the purpose of the embodiment, some or all of the cells are used. In addition, functional units in each embodiment may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The software functional units, if implemented as a product, used and sold, may be stored in a computer readable storage medium. Based on such understanding, the technical solutions proposed by the present disclosure can be implemented in the form of software products in nature or in part. Alternatively, a part of the technical solution that is advantageous to the conventional technology may be implemented in the form of a software product. A computer software product is stored in a storage medium and includes a plurality of instructions for causing a computing device (e.g., a personal computer, server, or network device) to perform all or a portion of the steps of the methods disclosed in the embodiments of the present disclosure. The storage medium includes: a U disk, a removable hard disk, a read-only Memory (ROM), a Random Access Memory (RAM), a floppy disk, and other various media capable of storing program codes.

While the disclosure has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the disclosure is not to be limited to the disclosed embodiment, but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

1. A terminal in a group communication system, comprising:

a memory;

a transceiver; and

a processor coupled to the memory and the transceiver,

wherein the processor is configured to:

performing group communication of a group by communicating with a first terminal using an interface; and

processing the interface between the terminal and the first terminal when the group communication of the group terminates the first terminal.

2. The terminal of claim 1, wherein the processor is configured to initiate AN Access Network (AN) release.

3. The terminal of claim 2, wherein the processor initiating the AN release further comprises: the processor decides to release the interface if the interface is used and all resources of the first terminal for the group communication termination of the group are released.

4. The terminal of claim 2, wherein the processor initiating the AN release further comprises: the interface and its associated tunnel are reserved with the group.

5. A terminal according to claim 4, wherein when creating the group, the terminal configures the interface and associated tunnels for the interface and selects the first terminal to serve the group in dependence on group information for the group.

6. A terminal as claimed in claim 4 or 5, wherein the interface and its associated tunnel are released when the group is de-allocated.

7. The terminal according to any of claims 1 to 6, wherein the terminal is a session management function, SMF, the first terminal is a user plane function, UPF, the group communication is a protocol data unit, PDU, session, and the interface is an Nx interface.

8. The terminal of claim 2, wherein the processor initiating the AN release further comprises: (R) AN decides to initiate a user equipment, UE, context release in (R) AN if there is AN acknowledged (R) AN condition or (R) AN internal cause.

9. The terminal of claim 8, wherein, when the (R) AN initiates the UE context release in the (R) AN, the (R) AN sends a UE context release request message to AN access and mobility management function (AMF).

10. The terminal of claim 9, wherein the UE context release request message includes a PDU session identification, ID, list indicating a plurality of PDU sessions served by the (R) AN of the UE.

11. The terminal of claim 10, wherein the AMF sends a UE context release command to the (R) AN if the AMF receives the UE context release request message or because AN internal AMF event includes receiving a service request or a registration request for establishing a non-access stratum NAS signaling connection through a next generation RAN NG RAN.

12. The terminal of claim 11, wherein if the AMF receives the service request or registration request for establishing NAS signaling connection through NG RAN, the AMF releases the old NAS signaling connection and continues service request or registration request procedure after successfully authenticating the UE.

13. The terminal of any of claims 10 to 12, wherein if AN (R) AN connection with the UE is not released:

a) the (R) AN requesting the UE to release the (R) AN connection, and the (R) AN deleting the context of the UE upon receiving AN (R) AN connection release acknowledgement from the UE; or

b) The (R) AN locally releases the RRC connection if the UE context release order indicates that the UE has locally released the radio resource control RRC connection.

14. The terminal of claim 13, wherein the (R) AN acknowledges the UE context release order by returning a UE context release complete message to the AMF, and a signaling connection for the UE between the AMF and the (R) AN is released.

15. The terminal of claim 14, wherein the AMF invokes a request to SMF including a PDU session ID, PDU session deactivation, cause, operation type, user location information, location information age, and/or session management, SM, information for each group communication in the UE context release complete.

16. The terminal of claim 15, wherein the SMF initiates a session modify request to the UPF indicating a need to un-tunnel information of AN, UPF terminating AN N3 interface, or UPF terminating AN Nx interface.

17. The terminal of claim 16, wherein the UPF initiates a session modification response to the SMF, the session modification response acknowledging the session modification request from the SMF.

18. The terminal of claim 15, wherein for each group communication in the UE context release complete, the SMF invokes the response to the AMF acknowledging the request comprising PDU session ID, PDU session deactivation, the cause, the operation type, the user location information, the location information age, and/or the session management SM information.

19. The terminal of claim 1, wherein the processor is configured to initiate a PDU session release.

20. The terminal of claim 19, wherein the processor initiates the PDU session release further comprises: when the terminating group communication of the first terminal is released, the first terminal, the interface and the associated tunnel of the interface are retained.

21. The terminal of claim 19, wherein the processor initiates the PDU session release further comprises: the first terminal, the interface and the associated tunnel with the interface are retained when all group communications terminating the group of first terminals are released.

22. The terminal of claim 19, wherein the processor initiates the PDU session release further comprises: when all group communications of the group are released or the group is released, the first terminal, the interface and the associated tunnel of the interface are released.

23. The terminal of claim 19, wherein the processor initiates the PDU session release further comprises: when all group communications terminating the group of the first terminal are released, the first terminal is released and/or the interface and its associated tunnel are released.

24. The terminal according to any of claims 19-23, wherein the first terminal is a UPF, the group communication is a PDU session, and the interface is an Nx interface.

25. The terminal of claim 19, wherein the processor initiates the PDU session release further comprises: releasing all resources associated with the PDU session, including an Internet Protocol (IP) address and/or prefix assigned to the IP-based PDU session and/or UPF resources used by the PDU session.

26. A method for performing group communication of terminals, comprising:

27. The method of claim 26, further comprising: and initiating the release of the access network AN.

28. The method of claim 27, wherein initiating the AN release further comprises: if the interface is used and all resources of the first terminal for the group communication termination of the group are released, the method comprises deciding to release the interface.

29. The method of claim 27, wherein initiating the AN release further comprises: the interface and its associated tunnel are reserved with the group.

30. The method of claim 29, wherein when creating the group, the method configures the interface and associated tunnels for the interface and selects the first terminal to serve the group according to group information for the group.

31. A method according to claim 29 or 30, wherein the interface and its associated tunnel are released when the group is de-allocated.

32. A method according to any of claims 26 to 31, wherein the terminal is a session management function, SMF, the first terminal is a user plane function, UPF, the group communication is a protocol data unit, PDU, session, and the interface is an Nx interface.

33. The method of claim 27, wherein initiating the AN release further comprises: (R) AN decides to initiate a user equipment, UE, context release in (R) AN if there is AN acknowledged (R) AN condition or (R) AN internal cause.

34. The method of claim 33, wherein, when the (R) AN initiates the UE context release in the (R) AN, the (R) AN sends a UE context release request message to AN access and mobility management function, AMF.

35. The method of claim 34, wherein the UE context release request message includes a PDU session identification, ID, list indicating a plurality of PDU sessions served by the (R) AN of the UE.

36. The method of claim 35, wherein the AMF sends a UE context release order to the (R) AN if the AMF receives the UE context release request message or because AN internal AMF event comprises receiving a service request or a registration request for establishing a non-access stratum NAS signaling connection through a next generation RAN, NG RAN.

37. The method of claim 36, wherein if the AMF receives the service request or registration request to establish a NAS signaling connection through a NG RAN, the AMF releases an old NAS signaling connection and continues a service request or registration request procedure after successfully authenticating the UE.

38. The method of any of claims 35 to 37, wherein if AN (R) AN connection with the UE is not released:

39. The method of claim 13, wherein the (R) AN acknowledges the UE context release order by returning a UE context release complete message to the AMF, and a signaling connection for the UE between the AMF and the (R) AN is released.

40. The method of claim 39, wherein the AMF invokes a request to SMF including a PDU session ID, a PDU session deactivation, a cause, an operation type, user location information, location information age, and/or Session Management (SM) information for each group communication in the UE context release complete.

41. The method of claim 40, wherein the SMF initiates a session modify request to the UPF indicating a need to un-tunnel information for AN, a UPF terminating AN N3 interface, or a UPF terminating AN Nx interface.

42. The method of claim 41, wherein the UPF initiates a session modification response to the SMF acknowledging a session modification request from the SMF.

43. The method of claim 40, wherein for each group communication in the UE context release complete, the SMF invokes the response to the AMF acknowledging the request comprising the PDU session ID, the PDU session deactivation, the cause, the operation type, the user location information, the location information age, and/or the Session Management (SM) information.

44. The method of claim 26, further comprising: initiating a PDU session release.

45. The method of claim 44, wherein initiating the PDU session release further comprises: when the terminating group communication of the first terminal is released, the first terminal, the interface and the associated tunnel of the interface are retained.

46. The method of claim 44, wherein initiating the PDU session release further comprises: the first terminal, the interface and the associated tunnel with the interface are retained when all group communications terminating the group of the first terminal are released.

47. The method of claim 44, wherein initiating the PDU session release further comprises: when all group communications of the group are released or the group is released, the first terminal, the interface and the associated tunnel of the interface are released.

48. The method of claim 44, wherein initiating the PDU session release further comprises: when all group communications terminating the group of the first terminal are released, the first terminal is released and/or the interface and its associated tunnel are released.

49. The method according to any of claims 44-48, wherein the first terminal is a UPF, the group communication is a PDU session, and the interface is an Nx interface.

50. The method of claim 44, wherein initiating the PDU session release further comprises: releasing all resources associated with the PDU session, including an Internet Protocol (IP) address and/or prefix assigned to the IP-based PDU session and/or UPF resources used by the PDU session.

51. A non-transitory machine-readable storage medium having stored thereon instructions which, when executed by a computer, cause the computer to perform the method of any one of claims 26 to 50.

52. A terminal device, comprising: a processor; and a memory for storing a computer program; the processor is for executing the computer program stored in the memory to perform the method of any of claims 26-50.