An enhanced secure delegation‐based anonymous authentication protocol for PCSs.

Summary: Rapid development of wireless networks brings about many security problems in portable communication systems (PCSs), 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. It is noticed that there is no delegation‐based protocol for PCSs, which can guarantee anonymity, untraceability, perfect forward secrecy, and resistance of denial‐of‐service (DoS) attack. Therefore, in this article, we put forward a novel delegation‐based anonymous and untraceable authentication protocol, which can guarantee to resolve all the abovementioned security issues and hence offer a solution for secure communications for PCSs. [ABSTRACT FROM AUTHOR]