Granted Patent B2

US 12,550,207 · App. 17/719,077 · Granted Feb 10, 2026

Inventors: Chien-Chun Huang-Fu (Hsin-Chu, TW); Chi-Hsien Chen (Hsin-Chu, TW)

Assignee: MediaTek Inc.

H04W76/11H04W36/0016H04W36/00224H04W76/38

Abstract

Claims (25)

1 . A method, comprising:

transmitting a protocol data unit (PDU) session establishment request message by a user equipment (UE) in a 5G system (5GS) to initiate a UE-requested PDU session establishment procedure;

detecting a UE-network collision upon receiving a PDU session release command message for a network-requested PDU session release procedure with a PDU session ID (PSI) in the received PDU session release command message being the same as a PSI in the transmitted PDU session establishment request message;

determining a release condition for the detected UE-network collision based on the UE-requested PDU session establishment procedure, wherein the release condition is satisfied when the UE-requested PDU session establishment procedure is to handover an existing PDU session; and

proceeding with the network-requested PDU session release procedure when the release condition is satisfied, wherein the UE aborts the UE-requested PDU session establishment procedure, otherwise,

ignoring the PDU session release command message when the release condition is not satisfied.

2 . The method of claim 1 , wherein the PDU session establishment request message carries a request type indicating whether the request is an initial request or is for an existing PDU session.

3 . The method of claim 2 , wherein the release condition is satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to handover an existing PDU session between 5G 3GPP access and 5G non-3GPP access.

4 . The method of claim 1 , wherein the network-requested PDU session release procedure involves UE transmitting a PDU session release complete message or a 5G session management (5GSM) status message to the 5GS.

5 . The method of claim 1 , wherein the aborting of the UE-requested PDU session establishment procedure involves UE stopping timer T3580, releasing an allocated Procedure Transaction identifier (PTI), and entering PROCEDURE TRANSACTION INACTIVE state.

6 . The method of claim 2 , wherein the UE determines that the release condition is not satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to establish a new PDU session.

7 . The method of claim 2 , wherein the UE determines that the release condition is not satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to handover an existing PDU session from S1 mode to N1 mode.

8 . The method of claim 1 , wherein the UE proceeds with the UE-requested PDU session establishment procedure when the release condition is not satisfied.

9 . A User Equipment (UE), comprising:

a transmitter that transmits a protocol data unit (PDU) session establishment request message in a 5G system (5GS) to initiate a UE-requested PDU session establishment procedure;

a receiver that detects a UE-network collision upon receiving a PDU session release command message for a network-requested PDU session release procedure with a PDU session ID (PSI) in the received PDU session release command message being the same as a PSI in the transmitted PDU session establishment request message;

a control circuit that determines a release condition for the detected UE-network collision based on the UE-requested PDU session establishment procedure, wherein the release condition is satisfied when the UE-requested PDU session establishment procedure is to handover an existing PDU session; and

a PDU session handling circuit that proceeds with the network-requested PDU session release procedure when the release condition is satisfied, wherein the UE aborts the UE-requested PDU session establishment procedure, otherwise, ignores the PDU session release command message when the release condition is not satisfied.

10 . The UE of claim 9 , wherein the PDU session establishment request message carries a request type indicating whether the request is an initial request or is for an existing PDU session.

11 . The UE of claim 10 , wherein the release condition is satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to handover an existing PDU session between 5G 3GPP access and 5G non-3GPP access.

12 . The UE of claim 9 , wherein the network-requested PDU session release procedure involves UE transmitting a PDU session release complete message or a 5G session management (5GSM) status message to the 5GS.

13 . The UE of claim 9 , wherein the aborting of the UE-requested PDU session establishment procedure involves UE stopping timer T3580, releasing an allocated and entering PROCEDURE TRANSACTION INACTIVE state.

14 . The UE of claim 10 , wherein the UE determines that the release condition is not satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to establish a new PDU session.

15 . The UE of claim 10 , wherein the UE determines that the release condition is not satisfied when the request type indicates that the UE-requested PDU session establishment request procedure is to handover an existing PDU session from S1 mode to N1 mode.

16 . The UE of claim 9 , wherein the UE proceeds with the UE-requested PDU session establishment procedure when the release condition is not satisfied.

Assignments (1)

Continuity (2)

References Cited (51)