36. Comments on “A Robust User Authentication Protocol with Privacy-Preserving for Roaming Service in Mobility Environments”

Roaming service under the global mobile network (GLOMONET) means that users who use mobile devices can still use mobile devices in other regions or countries after leaving their region or country. When mobile users use roaming services, the communication information transmitted by wireless channels is easy to be tampered with and eavesdropped on by attackers. These attacks may expose the identity and location of remote users. Thus, mutual authentication among mobile users, foreign agents, and home agents play an important role. To ensure a secure roaming service in a mobile network, it is necessary to design an efficient and secure solution. Recently, Shashidhara et al. proposed a user authentication protocol for roaming service in the GLOMONET. In this paper, we find that there are some security vulnerabilities in their protocol, including perfect forward secrecy (PFS), key compromise impersonation attacks (KCIA), and known-session-specific temporary information attacks (KTIA).