Security Weaknesses on a Delegation-Based Authentication Protocol for PCSs
Rapid development of wireless networks brings about many security problems in Portable Communication Systems (PCS), which can provide mobile users with an opportunity to enjoy global roaming services. In this regard, designing a secure user authentication scheme, especially for recognizing legal roaming users is indeed a challenging task. Recently, C-C Lee et al. proposed such scheme, which is claimed to be an improvement of T. F. Lee et al.’s protocol. However, in this article, we reveal that the scheme proposed by C-C Lee et al. still suffers from certain weaknesses like vulnerable to DoS attack, no perfect forward secrecy, loss of Untraceability, etc. Hence, C-C Lee et al.’s delegation-based protocol cannot guarantee secure communication for PCS environment.