Section: 5.3.8 Handling of timer T3502
Content: The value of timer T3502 can be sent by the network to the UE in the REGISTRATION ACCEPT message. The UE shall apply this value in all tracking areas of the registration area assigned to the UE, until a new value is received. The value of timer T3502 can be sent by the network to the UE in the REGISTRATION REJECT message during the initial registration. If a REGISTRATION REJECT message including timer T3502 value was received integrity protected, the UE shall apply this value until a new value is received with integrity protection or a new PLMN or SNPN is selected. Otherwise, the default value of this timer is used. The default value of this timer is also used by the UE in the following cases: a) REGISTRATION ACCEPT message is received without a value specified, and the 5GS registration type IE in the REGISTRATION REQUEST message is not set to "periodic registration updating”; b) the UE does not have a stored value for this timer; c) a new PLMN which is not in the list of equivalent PLMNs or a new SNPN has been entered, the initial registration procedure fails, the registration attempt counter is equal to 5 and no REGISTRATION REJECT message was received from the new PLMN or SNPN; d) the network indicates that the timer is "deactivated"; or e) a new PLMN which is not in the list of equivalent PLMNs or a new SNPN has been entered, the registration procedure for mobility and periodic registration update fails and the registration attempt counter is equal to 5.