1. User equipment (UE) comprising:a communications interface;
a processor; and
one or more components operated by the processor to perform operations comprising:
generating a registration request, wherein content of the registration request comprises:
registration information associated with the UE; and
data indicating a request type of a subsidiary request related to the UE;
transmitting the registration request via the communications interface; and
receiving an acknowledgement indicating both a status of the registration request and a status of the subsidiary request.