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EP-4740368-A1 - METHOD AND APPARATUS FOR MESSAGE TRANSMISSION

EP4740368A1EP 4740368 A1EP4740368 A1EP 4740368A1EP-4740368-A1

Abstract

Embodiments of the present disclosure provide method and apparatus for message transmission. A method performed by a first SMF may comprise determining first information. The first information indicates that a second SMF does not need to report at least one item to the first SMF when no other item needs to be transferred to the first SMF. The method may further comprise sending the first information to the second SMF.

Inventors

  • LU, YUNJIE
  • ZHU, JINYIN
  • ZHOU, ZONGMING
  • ZHU, TING
  • HE, Yingjiao

Assignees

  • Telefonaktiebolaget LM Ericsson (publ)

Dates

Publication Date
20260513
Application Date
20240624

Claims (20)

  1. A method (300) performed by a first session management function, SMF, comprising: determining (302) first information, wherein the first information indicates that a second SMF does not need to report at least one item to the first SMF when no other item needs to be transferred to the first SMF; and sending (304) the first information to the second SMF.
  2. The method according to claim 1, wherein the first information is used for suppressing sending the at least one item to the first SMF.
  3. The method according to claim 2, wherein suppressing sending the at least one item to the first SMF comprises: if no other item needs to be transferred to the first SMF, suppressing sending a dedicated message to the first SMF to inform the at least one item.
  4. the method according to any of claims 1-3, wherein the first information further indicates that the second SMF sends to the first SMF a message comprising the at least one item when at least one other item needs to be transferred to the first SMF, wherein the message further comprises the at least one other item.
  5. The method according to claim 1-4, wherein the first information is determined based at least partly on at least one of: a policy and/or charging function has not provisioned an event trigger for one or more items of the at least one item to the first SMF, wherein the first SMF will not report the one or more items of the at least one item to the policy and/or charging function, the first SMF has subscribed an event report of one or more items of the at least one item using an event exposure service that doesn't need an interaction with the second SMF, or the first SMF does not need one or more items of the at least one item.
  6. The method according to any of claims 1-5, wherein the first information is sent to the second SMF in at least one of: a protocol data unit, PDU, session create response, a PDU session update request, or a PDU session context response.
  7. The method according to any of claims 1-6, wherein the first information is sent to the second SMF during at least one of: a PDU session establishment procedure, a lifetime of a PDU session, or a user equipment mobility procedure with the second SMF insertion.
  8. The method according to any of claims 1-7, wherein the first information is comprised in at least one of: PDU session created data, visited session management function update data, or a session management context.
  9. The method according to any of claims 1-8, wherein the at least one item comprises at least one changed item.
  10. The method according to any of claims 1-9, wherein the at least one item comprises at least one of: a serving network, an access network type, an additional access network type, a radio access technology type, a user equipment location, a user equipment time zone, an additional user equipment location, information indicating that a user equipment is in or out of a local area data network service area, a security result associated to a PDU session, user plane security information associated to a PDU session, information indicating whether a user equipment requests to setup an always-on PDU session, information indicating whether a PDU session can be moved to an evolved packet system and whether N26 interface to be used during an evolved packet system interworking procedure, a usage data report for a secondary radio access technology for a quality of service flow, a usage data report for a secondary radio access technology for a quality of service flow and/or a whole PDU session, information indicating whether an access network type associated to a PDU session can be changed, information indicating an access to be released, information indicating whether a PDU session is allowed to be upgraded to multi access PDU session, information indicating whether a multi access PDU session is requested, information indicating an access that is unavailable, or information indicating a maximum integrity protected data rate supported by a user equipment for downlink.
  11. The method according to any of claims 1-10, further comprising: sending (312) to the second SMF a message for updating the at least one item or deleting the first information.
  12. The method according to any of claims 1-11, wherein the first SMF comprises at least one of: an anchor SMF, or a home SMF.
  13. The method according to any of claims 1-12, wherein the second SMF comprises at least one of: an intermediate SMF, or a visited SMF.
  14. A method (400) performed by a second session management function, SMF, comprising: receiving (402) first information from a first SMF or an old second SMF, wherein the first information indicates that the second SMF does not need to report at least one item to the first SMF when no other item needs to be transferred to the first SMF; and obtaining (404) the at least one item.
  15. The method according to claim 14, further comprising: suppressing (406) sending the at least one item to the first SMF based on the first information.
  16. The method according to claim 15, wherein suppressing sending the at least one item to the first SMF based on the first information comprises: if no other item needs to be transferred to the first SMF, suppressing sending a dedicated message to the first SMF to inform the at least one item.
  17. The method according to any of claims 14-16, further comprising: sending (408) to the first SMF a message comprising the at least one item when at least one other item needs to be transferred to the first SMF, wherein the message further comprises the at least one other item.
  18. The method according to any of claims 14-17, wherein the first information is received from the first SMF in at least one of: a protocol data unit, PDU, session create response, a PDU session update request, or a PDU session context response.
  19. The method according to any of claims 14-18, wherein the first information is received from the old second SMF in a PDU session context response.
  20. The method according to any of claims 14-19, wherein the first information is received from the first SMF during at least one of: a PDU session establishment procedure, a lifetime of a PDU session, or a user equipment mobility procedure with the second SMF insertion.

Description

METHOD AND APPARATUS FOR MESSAGE TRANSMISSION TECHNICAL FIELD The non-limiting and exemplary embodiments of the present disclosure generally relate to the technical field of communications, and specifically to methods and apparatuses for message transmission. BACKGROUND This section introduces aspects that may facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art. In communication networks, there may be various sessions such as protocol data unit (PDU) sessions. The PDU sessions may be established in various ways. For example, a user equipment (UE) may initiate a PDU session establishment procedure. A network may trigger a PDU session establishment procedure. The PDU session may be managed by a session management function (SMF) . When a UE is outside of a network function (NF) (such as SMF) service area, or a current NF (such as SMF) cannot serve a target data network (DN) access identifier (DNAI) for a traffic routing for a local access to a DN, an intermediate NF may be inserted. For example, intermediate SMF (I-SMF) may be inserted between the SMF and the Access and Mobility Management Function (AMF) . The I-SMF has an N11 interface with the AMF and an N16a interface with the SMF and is responsible for controlling the user plane function (s) (UPF (s) ) that the SMF cannot directly control. The exchange of the session management (SM) context and forwarding of tunnel information if needed are done between two SMFs directly without involvement of AMF. Depending on scenario, a PDU session in non-roaming case or local breakout is either served by a single SMF or served by an SMF and an I-SMF. When a PDU session is served by both an SMF and an I-SMF, the SMF is the NF instance that has the interfaces towards the policy control function (PCF) and charging function (CHF) . Clauses 4.23.2-16 of 3rd Generation Partnership Project (3GPP) Technical Specification (TS) 23.502 V18.1.1, the disclosure of which is incorporated by reference herein in its entirety, describes various I-SMF related procedures such as I-SMF insertion/change/removal procedures. In the case of roaming for a home routed PDU session, the following cases may occur: A UE moves out of visited SMF (V-SMF) serving area in a serving public land mobile network (PLMN) ; A UE moves to another (serving) visited PLMN (VPLMN) ; A UE moves between home PLMN (HPLMN) and a VPLMN. In the above cases, the procedures in clauses 4.23.2-16 of 3GPP TS 23.502 V18.1.1 for I-SMF apply to the V-SMF insertion/change/removal by replacing the I-SMF with V-SMF, and SMF with H-SMF. For an established PDU session, an I-SMF is inserted if a UE is not in the SMF service area. In this case, when a UE moves from HPLMN to a VPLMN, a V-SMF is inserted and the I-SMF is removed. For mobility from VPLMN to HPLMN, an I-SMF is inserted and the V-SMF is removed. The procedures of clauses 4.23.2-16 of 3GPP TS 23.502 V18.1.1 apply in this case, i.e. by replacing the target or new I-SMF by a V-SMF for mobility from HPLMN to VPLMN and by replacing the source or old I-SMF by a V-SMF for mobility from VPLMN to HPLMN. Various information, such as PduSessionCreateData, HsmfUpdateData, etc., may be transmitted between two NFs such as SMFs. PduSessionCreateData may be sent from the V-SMF or I-SMF to H-SMF or anchor SMF (A-SMF) . PduSessionCreateData may be a representation of the PDU session to be created in the H-SMF or A-SMF. Table 1 shows an example of PduSessionCreateData, which is a part of Table 6.1.6.2.9-1 of 3GPP TS 29.502 V18.2.0, the disclosure of which is incorporated by reference herein in its entirety. UICC denotes Universal Integrated Circuit Card. ID denotes identifier. EPS denotes Evolved Packet System. 5GS denotes fifth generation system. SM denotes session management. IE denotes information element. LADN denotes Local Area Data Network. SNPN denotes Stand-alone Non-Public Network. GUAMI denotes Globally Unique AMF Identifier. Table 1: Definition of type PduSessionCreateData HsmfUpdateData may be sent from the H-SMF or A-SMF to V-SMF or I-SMF. PduSessionCreateData may be a representation of the updates to apply to the PDU session. Table 2 shows an example of HsmfUpdateData, which is a part of Table 6.1.6.2.11-1 of 3GPP TS 29.502 V18.2.0. MAPDU denotes Multi-Access PDU. NID denotes Network Identifier. UTC denotes Coordinated Universal Time. RAT denotes Radio Access Technology. Table 2: Definition of type HsmfUpdateData Policy Control Request Trigger may be sent from the PCF or CHF to H-SMF or A-SMF. Table 3 shows an example of Policy Control Request Trigger, which is same as Table 5.6.3.6-1 of 3GPP TS 29.512 V18.1.0, the disclosure of which is incorporated by reference herein in its entirety. Table 3: Enumeration PolicyControlRequestTrigger SUMMARY This summary is provided to introduce a selection of concept