A Dynamic-verifier Based Authenticated Key Exchange Protocol

Abstract

Traditional design of authenticated key exchange protocol considers communication security, but seldom takes into account the security threat of server compromises. Whenever an authentication server is captured, the intruder can immediately masquerade as legitimate users to successfully log into the system. Although some zero-knowledge-proof methods were designed to relieve this threat, their computation is relatively high due to computationally heavy modular exponentiations employed. A dynamic-verifier based authenticated key exchange protocol is proposed, where the server stores a dynamically changing password-verifier and no password leakage would occur even when the server’s verifier database is stolen. DV-AKE is especially useful for applications where lightweight client is required or lower server computational load is preferred.