Cryptanalysis of an optimized protocol for mobile network authentication and security

Abstract

Yi et al. presented a protocol for mobile network authentication and key distribution based upon the DSA signature scheme. The protocol can be divided into two phases, i.e., registration phase and service phase. In this paper, we show that their scheme is insecure on the registration phase since an attacker can easily forge a certification for any exit or dummy user in their protocol and then pretend to be a legal user to communicate with other entities.