Maintenance of forbidden tacking area list in NR systems

A method comprising:

• maintaining a forbidden tracking area identifier (TAI) list by a user equipment (UE) in a mobile communication network, wherein the forbidden TAI list comprises a list of TAs where the UE is forbidden to receive services from the network;
• transmitting a registration request to the network;
• receiving a registration accept message from the network in response to the registration request, wherein the registration accept message carries a service area list that comprises at least one allowed TAI;
• and
• removing the allowed TAI from the forbidden TAI list when a removing condition is satisfied, wherein the removing condition comprises the UE finds a matching of the allowed TAI in the forbidden TAI list, wherein the registration request carries a registration type of emergency registration, and wherein the removing condition is not satisfied.

A User Equipment (UE), comprising:

• memory that stores a forbidden tracking area identifier (TAI) list in a mobile communication network, wherein the forbidden TAI list comprises a list of TAs where the UE is forbidden to receive services from the network;
• a receiver that receives a service area list from the network, wherein the service area list comprises at least one allowed TAI;
• and
• a TAI list maintenance circuit that removes the allowed TAI from the forbidden TAI list when a removing condition is satisfied, wherein the removing condition comprises the UE finds a matching of the allowed TAI in the forbidden TAI list, wherein the removing condition is not satisfied when the UE is registered for emergency services.

A User Equipment (UE), comprising:

• memory that stores a forbidden tracking area identifier (TAI) list in a mobile communication network, wherein the forbidden TAI list comprises a list of TAs where the UE is forbidden to receive services from the network;
• a transmitter that transmits a registration request to the network, wherein the UE receives a registration accept message from the network in response to the registration request, wherein the registration accept message carries a service area list that comprises at least one allowed TAI;
• and
• a TAI list maintenance circuit that removes the allowed TAI from the forbidden TAI list when a removing condition is satisfied, wherein the removing condition comprises the UE finds a matching of the allowed TAI in the forbidden TAI list, wherein the registration request carries a registration type of emergency registration, and wherein the removing condition is not satisfied.