In this paper we propose a new anonymous password-based authenticated key exchange protocol. The communication cost of our protocol is sub-linear O, which improves a previous one of 0(N) cost, where N is the number of users in the system. We show that the session key is secure against an active adversary in the random oracle model and identity anonymity is secure against a semi-honest adversary in the standard model.
- Anonymous authentication
- Authenticated key exchange
- Homomorphic encryption
- Password based authentication
- Private information retrieval