Patent ID: 8280053

Claim:
An authentication method between a first entity and a second entity in a telecommunication network, comprising steps of: storing first keys allocated to said second entity in non-volatile storage in the first and second entities for use in a plurality of authentication sessions between the first and the second entities, and for each of the plurality of authentication sessions, performing the following operations: applying the first keys and a random number produced by the first entity and transmitted by the first entity to the second entity to first algorithms stored in the first entity and the second entity; comparing, in the second entity, a signature produced by the first algorithm in the first entity and transmitted with the random number to the second entity and a signature result produced by the first algorithm in the second entity, applying second keys, different from said first keys and allocated to said second entity, and stored in non-volatile storage in the first and second entities, and the random number produced by the first entity and transmitted by the first entity to the second entity to second identical algorithms stored in the first and second entities, only when the transmitted signature and the signature result are identical; comparing, in the first entity, a response produced by the second algorithm stored in the second entity and transmitted to the first entity and a response result produced by the second algorithm stored in the first entity; enabling communications to take place between said first and second entities if the response transmitted by the first entity is identical to the response produced in the second entity.