Patent ID: 11895487
Assignee: ORANGE
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A determining method for determining a key to secure a communication between a user equipment and an application server, said method comprising:
authenticating the user equipment by an authentication server a mobile communication network, a secret master key being generated, during said authenticating, by the user equipment and the authentication server;
after the secret master key is generated by the user equipment and the authentication server, receiving by the authentication server a key request that was sent by the user equipment with a view to communicating with the application server;
sending a random variable by the authentication server to the user equipment after receiving the key request from the user equipment; and
computing said key by using a key derivation function applied to at least the random variable, a user identifier and an identifier of the application server and using the master key.