Patent ID: 8417955

Claim:
A method for two-way entity authentication, comprising: transmitting, by a first entity, a first message carrying a time variant parameter R A , an entity identity ID A and a signature; transmitting, by a second entity, upon reception of the first message, to a trusted third party a second message carrying time variant parameters R A and R B , the entity identity ID A of the first entity and an entity identity ID B of the second entity; returning, by the trusted third party, upon reception of the second message, to the second entity a third message carrying a signature of the trusted third party and the time variant parameters R A and R B ; obtaining, by the second entity, upon reception of the third message, a verification result for the first entity if verification of the signature of the trusted third party is passed and the time variant parameter R B is consistent with a locally stored time variant parameter R B , and if the verification result indicates that the first entity is valid, then obtaining a public key of the first entity to verify the signature of the first entity in the first message, and if the verification is passed, then transmitting a fourth message carrying the signature of the trusted third party, a signature of the second entity and the time variant parameter R A ; and obtaining, by the first entity, upon reception of the fourth message, a verification result for the second entity if verification of the signature of the trusted third party is passed and the time variant parameter R A is consistent with a locally stored time variant parameter R A , and if the verification result indicates that the second entity is valid, then obtaining a public key of the second entity to verify the signature of the second entity in the fourth message, thereby completing the authentication.