Method, device, and system for core network device re-allocation in wireless network

Patent metadata

Field	Value
Publication number	US-2024007983-A1
Application number	US-202318465317-A
Country	US
Kind code	A1
Filing date	Sep 12, 2023
Priority date	May 17, 2021
Publication date	Jan 4, 2024
Grant date	—

Abstract

This disclosure generally relates performing UE authentication and registration with the core network, and in particular, to supporting secure interactions between the UE and the target AMF when the UE is re-allocated to the target AMF. After the UE initiates a first registration request, the initial AMF may retrieve a candidate AMF list and selects a target AMF to serve the UE. The initial AMF generates a 5G-GUTI for the UE, based on the selected target AMF. The initial AMF requests the UE to initiate a second registration request, by using the generated 5G-GUTI. With the solutions provided in this disclosure, the message interactions between the UE and the target AMF are integrity protected and/or ciphered, without the need to upgrade the UE and without using an indirect connection of the core network.

First claim

1 . A method for performing secure re-allocation of a UE from an initial core network element to a target core network element in a communication network, performed by the initial core network element, the method comprising:
receiving, from a first network element, a first message comprising a list of candidate core network elements; selecting the target core network element from the list of candidate core network elements; and generating a 5G Global Unique Temporary Identifier (5G-GUTI) for the UE based on the target core network element, the 5G-GUTI being used by the UE, after a first registration request initiated by the UE, to initiate a second registration request.

2 . The method of claim 1 , wherein the 5G-GUTI is used to replace an original 5G-GUTI carried in the first registration request.

3 . The method of claim 1 , wherein generating the 5G-GUTI for the UE based on the target core network element comprises:
during a registration procedure triggered by the first registration request, generating the 5G-GUTI for the UE based on the target core network element.

4 . The method of claim 1 , wherein before receiving the first message, the method further comprises:
determining that the initial core network element does not support at least one of:
a network slice subscribed by the UE; or
a network function subscribed by the UE.

5 . The method of claim 1 , wherein:
the first network element comprises a Network Repository Function (NRF) before receiving the first message, the method further comprises transmitting a Nnrf_NFDiscovery_request message to the first network element; and the first message is received in response to the Nnrf_NFDiscovery_request message and comprises a Nnrf_NFDiscovery_response message.

6 . (canceled)

7 . The method of claim 1 , further comprising:
transmitting, to the UE, a second message indicating that the first registration request is accepted, the second message comprising the 5G-GUTI, wherein the second message comprises a registration accept message.

8 . (canceled)

9 . The method of claim 7 , further comprising:
transmitting an N2 UE context release message to an access network element of the communication network, the access network element providing the UE an access to the communication network, the N2 UE context release message being used to release an N2 signaling connection for the UE between the access network element and the initial core network element.

10 . The method of claim 9 , wherein the N2 UE context release message further triggers the access network element to release a radio access network connection with the UE and delete a context of the UE.

11 . The method of claim 9 , wherein the access network element comprises at least one of a gNB, an eNB, a nodeB, or a Non-3GPP Interworking Function (N3IWF).

12 . The method of claim 7 , further comprising:
transmitting, to the UE, a third message triggering the UE to start a subsequent registration procedure based on the 5G-GUTI, wherein the third message comprises one of:
a UE configuration update command; or
a de-registration request message.

13 . (canceled)

14 . The method of claim 12 , wherein the UE configuration update command carries a registration indication.

15 . The method of claim 12 , wherein the de-registration request message carries a registration indication.

16 . The method of claim 12 , wherein:
the third message triggers the UE to transmit a second registration request message to an access network element of the communication network for registering with the target core network element based on the 5G-GUTI, the second registration request message comprising an information element being indicative of the 5G-GUTI, the 5G-GUTI being indicative of the target core network element.

17 . The method of claim 16 , further comprising:
in response to receiving the second registration request message:
determining, by the access network element, the target core network element based on one of:
the 5G-GUTI carried in the second registration request message;
a shortened form of the 5G-GUTI carried in the second registration request message; or
the shortened form of the 5G-GUTI carried in a fourth message for establishing a connection between the UE and the access network element; and

forwarding, by the access network element, the second registration request message to the target core network element.

18 . The method of claim 17 , wherein the fourth message comprises a Radio Resource Control (RRC) message, the RRC message being associated with the second registration request message.

19 . The method of claim 17 , wherein the shortened form of the 5G-GUTI comprises a 5G S-Temporary Mobile Subscriber Identity (5G-S-TMSI).

20 . The method of claim 1 , wherein the initial core network element comprises an AMF.

21 . The method of claim 1 , wherein the target core network element comprises an AMF.

22 - 23 . (canceled)

24 . An initial core network element for performing secure re-allocation of a UE from the initial core network element to a target core network element, the initial core network element comprising a memory for storing computer instructions and a processor in communication with the memory, wherein, when the processor executes the computer instructions, the processor is configured to cause the initial core network element to:
receive, from a first network element, a first message comprising a list of candidate core network elements; select the target core network element from the list of candidate core network elements; and generate a 5G Global Unique Temporary Identifier (5G-GUTI) for the UE based on the target core network element, the 5G-GUTI being used by the UE, after a first registration request initiated by the UE, to initiate a second registration request.

25 . A non-transitory storage medium for storing computer readable instructions, the computer readable instructions, when executed by a processor in an initial core network element, causing the processor to:
receive, from a first network element, a first message comprising a list of candidate core network elements; select, from the list of candidate core network elements, a target core network element to which a UE is to-be re-allocated from the initial core network element; and generate a 5G Global Unique Temporary Identifier (5G-GUTI) for the UE based on the target core network element, the 5G-GUTI being used by the UE, after a first registration request initiated by the UE, to initiate a second registration request.

Assignees

• Zte Corp

Inventors

• Liu Yuze
• You Shilin
• Zhu Jinguo
• Huang He
• Liang Shuang
• Zhou Xingyue
• Peng Jin
• Xing Zhen
• Lin Zhaoji

Classifications

• H04W60/04 Primary

  using triggered events · CPC title

• H04W48/20

  Selecting an access point · CPC title

• H04W8/065

  involving selection of the user mobility server · CPC title

• H04W8/26

  Network addressing or numbering for mobility support · CPC title

• H04W12/06

  Authentication · CPC title