Efficient user identification scheme with key distribution preserving anonymity for distributed computer networks

In 2000, Lee and Chang (Comput Syst Sci Eng 15 (2000) 211) presented a user identification scheme that also can simultaneously achieve key exchange requirement while preserving the user anonymity. Their idea is valuable especially when it is applied to some applications in which the identity of the user should be protected from the public in the distributed computer networks. Unfortunately, our paper shows that their scheme is insecure under two attacks and we further proposed a more efficient identification scheme preserving the same merits. The proposed scheme not only effectively eliminates the security leaks of the Lee-Chang scheme, but also reduces computational complexities and communication costs as compared with their scheme.