Method and system for transmission of SUSI in the NAS procedure
The present disclosure is related to sending of a one time identifier of a UE during the NAS procedure. Specifically, the present disclosure relates to determining whether to use same one time identifier or different one time identifier during registration retry procedure.
1. A method for a User Equipment (UE), the method comprising:
sending, to an Access and mobility Management Function (AMF), a Non-Access Stratum (NAS) message, the NAS message including a first Subscribed Unique Concealed Identifier (SUCI) for identifying the UE, wherein the first SUCI is generated by concealing a Subscriber Unique Permanent Identifier (SUPI) for permanently identifying the UE; and
starting a timer, in a case where the NAS message has been sent,
wherein the method further comprises:
sending, to the AMF, a Deregistration Request message, as a deregistration procedure, wherein
the Deregistration Request message includes the first SUCI that was sent in the NAS message if the timer is running, or
the Deregistration Request message includes a second SUCI that is generated by concealing the SUPI if the timer is not running, the second SUCI being different from the first SUCI.
2. The method according to claim 1 , wherein
the UE initiates the deregistration procedure due to one of:
the UE switched off;
Universal Subscriber Identity Module (USIM) of the UE is removed; and
5G system (5GS) capability of the UE is disabled.
3. The method according to claim 1 , wherein
the UE does not have a valid 5G Globally Unique Temporary Identifier (5G-GUTI).
4. The method according to claim 1 , wherein
the NAS message is a registration request message.
5. The method according to claim 1 , further comprising:
receiving an Identity Request message requesting the UE to send a SUCI,
wherein the NAS message is an Identity Response message for the Identity Request message.
6. A User Equipment (UE) comprising:
a transceiver configured to communicate with a Next Generation Radio Access Network (NG-RAN); and
a controller configured to send, to an Access and mobility Management Function (AMF) via the NG-RAN, a Non-Access Stratum (NAS) message, the NAS message including a first Subscribed Unique Concealed Identifier (SUCI) for identifying the UE,
wherein the first SUCI is generated by concealing a Subscriber Unique Permanent Identifier (SUPI) for permanently identifying the UE,
wherein the controller is further configured to:
start a timer, in a case where the NAS message has been sent, and
send, to the AMF via the NG-RAN, a Deregistration Request message, as a deregistration procedure, wherein
the Deregistration Request message includes the first SUCI that was sent in the NAS message if the timer is running, or
the Deregistration Request message includes a second SUCI that is generated by concealing the SUPI if the timer is not running, the second SUCI being different from the first SUCI.
7. The UE according to claim 6 , wherein
the controller configured to initiate the deregistration procedure due to one of:
the UE switched off;
a Universal Subscriber Identity Module (USIM) of the UE is removed; and
5G system (5GS) capability of the UE is disabled.
8. The UE according to claim 6 , wherein
the controller does not have a valid 5G Globally Unique Temporary Identifier (5G-GUTI) and the first SUCI is available.
9. The UE according to claim 6 , wherein
the controller configured to send the NAS message as a registration request message including the first SUCI.
10. The UE according to claim 6 , wherein:
the controller configured to send the NAS message as an Identity Response message including the first SUCI, in a case where the controller receives an Identity Request message requesting the UE to send a SUCI.