5.3.2.2.3 RM-REGISTERED state

In the RM-REGISTERED state, the UE is registered with the network. In the RM-REGISTERED state, the UE can receive services that require registration with the network.

In the RM-REGISTERED state, the UE shall:

• perform Mobility Registration Update procedure if the current TAI of the serving cell (see TS 37.340 [31]) is not in the list of TAIs that the UE has received from the network in order to maintain the registration and enable the AMF to page the UE;

NOTE: Additional considerations for Mobility Registration Update in case of NR satellite access are provided in clause 5.4.11.6.

• perform Periodic Registration Update procedure triggered by expiration of the periodic update timer to notify the network that the UE is still active.
• perform a Mobility Registration Update procedure to update its capability information or to re-negotiate protocol parameters with the network;
• perform Deregistration procedure (see clause 4.2.2.3.1 of TS 23.502 [3]) and enter RM-DEREGISTERED state, when the UE needs to be no longer registered with the PLMN. The UE may decide to deregister from the network at any time.
• enter RM-DEREGISTERED state when receiving a Registration Reject message or a Deregistration message. The actions of the UE depend upon the cause value' in the Registration Reject or Deregistration message. See clause 4.2.2 of TS 23.502 [3].

When the UE RM state in the AMF is RM-REGISTERED, the AMF shall:

• perform Deregistration procedure (see clauses 4.2.2.3.2, 4.2.2.3.3 of TS 23.502 [3]) and enter RM-DEREGISTERED state for the UE, when the UE needs to be no longer registered with the PLMN. The network may decide to deregister the UE at any time;
• perform Implicit Deregistration at any time after the Implicit Deregistration timer expires. The AMF shall enter RM-DEREGISTERED state for the UE after Implicit Deregistration;
• when applicable, accept or reject Registration Requests or Service Requests from the UE.