REGISTRATION METHODS USING ONE-TIME IDENTIFIERS FOR USER EQUIPMENTS AND NODES IMPLEMENTING THE REGISTRATION METHODS

A user equipment (UE) uses a one-time identifier to identify itself in a registration request sent to a trusted core network (CN) node. The one-time identifier is in the form of a first temporary identifier. The trusted CN node registers the UE, generates a next temporary identifier, and sends a random challenge to the UE. The UE uses the random challenge to generate a copy of the next temporary identifier and stores the next temporary identifier in a memory. Then, until a next registration, the UE and the trusted CN node use the first temporary identifier to identify the UE when communicating with each other and with other trusted and untrusted CN nodes. In the next registration event, the UE uses the next temporary identifier to identity itself to the trusted CN node. A true identity of the UE is not detectable by an untrusted node that may become compromised.