Method and apparatus for p-cscf restoration

Patent metadata

Field	Value
Publication number	US-2025317348-A1
Application number	US-202218725879-A
Country	US
Kind code	A1
Filing date	Dec 27, 2022
Priority date	Jan 7, 2022
Publication date	Oct 9, 2025
Grant date	—

Abstract

Embodiments of the present disclosure provide method and apparatus for P-CSCF restoration. A method performed by a session management node comprises receiving a message from a data management node or a policy control node or a first access and mobility node. The message indicates proxy call session control function (P-CSCF) restoration and information of a failed P-CSCF. The method further comprises, for a protocol data unit (PDU) session, based on the received message, triggering a P-CSCF restoration procedure by sending a PDU session release command or a PDU session modification command to a user equipment via the first or a second access and mobility node. The PDU session modification command comprises an updated P-CSCF list based on the information of the failed P-CSCF.

First claim

1 . A method performed by a session management node, comprising:
receiving a message from a data management node or a policy control node or a first access and mobility node, wherein the message indicates proxy call session control function, P-CSCF, restoration and information of a failed P-CSCF; deriving address information of Gm interface of the failed P-CSCF from the information of the failed P-CSCF; and for a protocol data unit, PDU, session, based on the received message, triggering a P-CSCF restoration procedure by sending a PDU session release command or a PDU session modification command to a user equipment via the first or a second access and mobility node, wherein the PDU session modification command comprises an updated P-CSCF list based on the information of the failed P-CSCF; wherein the failed P-CSCF is detected by a serving CSCE, S-CSCF.

2 . (canceled)

3 . The method according to claim 1 , wherein when the message is received from the data management node, the message is an Nudm_UECM_PCscfRestoration notification.

4 . The method according to claim 1 , wherein when the message is received from the policy control node, the message is an Npcf_SMPolicyControl_UpdateNotify Request.

5 . The method according to claim 1 , wherein when the message is received from the first access and mobility node, the message is an Nsmf_PDUSession_UpdateSMContext Request.

6 . The method according to claim 1 , wherein the session management node comprises a session management function, SMF, the first and second access and mobility nodes comprise an access and mobility management function, AMF, the data management node comprises a unified data management, UDM, and the policy control node comprises a policy control function, PCF.

7 . The method according to claim 1 , wherein the information of the failed P-CSCF comprises at least one of:
an Internet protocol version 4 address of Mw interface of the failed P-CSCF, a network function instance identifier the failed P-CSCF, an Internet protocol version 6 address of Mw interface of the failed P-CSCF, or a fully qualified domain name of Mw interface of the failed P-CSCF.

8 . The method according to claim 1 , wherein the PDU session modification command is sent to the user equipment when the user equipment supports P-CSCF re-selection.

9 . (canceled)

10 . The method according to claim 1 , further comprising:
marking the failed P-CSCF as temporarily not available for a period of time, wherein information of the failed P-CSCF will not be sent to a user equipment when allocating a P-CSCF list for a user equipment during the period of time.

11 . A method performed by a data management node, comprising:
receiving a request for initiating proxy call session control function, P-CSCF, restoration from a home subscriber server, HSS, wherein the request comprises information of a failed P-CSCF; and sending a message to a session management node or an access and mobility node, wherein the message indicates proxy call session control function, P-CSCF, restoration indication and the information of a failed P-CSCF.

12 . The method according to claim 11 , wherein the failed P-CSCF is detected by a serving CSCF, S-CSCF.

13 . (canceled)

14 . (canceled)

15 . The method according to claim 11 , wherein the information of the failed P-CSCF comprises at least one of:
an Internet protocol version 4 address of Mw interface of the failed P-CSCF, a network function instance identifier the failed P-CSCF, an Internet protocol version 6 address of Mw interface of the failed P-CSCF, or a fully qualified domain name of Mw interface of the failed P-CSCF.

16 - 28 . (canceled)

29 . A session management node, comprising:
a processor; and a memory coupled to the processor, said memory containing instructions executable by said processor, whereby said session management node is operative to:
receive a message from a data management node or a policy control node or an access and mobility node, wherein the message indicates proxy call session control function, P-CSCF, restoration indication and information of a failed P-CSCF;
derive address information of Gm interface of the failed P-CSCF from the information of the failed P-CSCF; and
for a protocol data unit, PDU, session, based on the received message, trigger a P-CSCF restoration procedure by sending a PDU session release command or a PDU session modification command to a user equipment via the first or a second access and mobility node,
wherein the PDU session modification command comprises an updated P-CSCF list based on the information of the failed P-CSCF; and wherein the failed P-CSCF is detected by a service CSCF, S-CSCF.

30 . The session management node according to claim 29 , wherein when the message is received from the data management node, the message is an Nudm_UECM_PCscfRestoration notification.

31 - 38 . (canceled)

Assignees

• Ericsson Telefon Ab L M

Inventors

• He Yingjiao
• De Gregorio Rodriguez Jesus Angel
• Garcia Azorero Fuencisla
• Zhan Deqin
• Li Bin
• Zhu Jinyin
• Li Beibei

Classifications

• H04L41/0894

  Policy-based network configuration management · CPC title

• H04L65/1045

  Proxies, e.g. for session initiation protocol [SIP] · CPC title

• H04W76/30

  Connection release · CPC title

• H04L41/082

  the condition being updates or upgrades of network functionality · CPC title

• H04L41/0668 Primary

  by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure · CPC title