Secure Password Authentication Protocol in Wireless Networks

In 2006, Ma et al. found flaws in the original and fixed versions of the PAP protocol by using a new knowledge-based framework, and presented an enhanced PAP (M-PAP) protocol. The current paper, however, demonstrates that Ma et al.'s M-PAP protocol is still vulnerable to off-line password guessing attacks. Then, we present an improvement to the protocol, in order to isolate such a problem