Abstract
Mobile Internet access has significantly increased over the past few years. Roaming into foreign networks becomes necessary in order to access mobile-services. Traditionally, this done based on roaming agreement between the home network and the foreign network to extend trust for mobile users. However, secured mobile authentication is a challenge especially in two-party authentication environment where only the visited user and the foreign network get involved. This paper proposes two-party secure roaming protocols based on direct negotiation with potential foreign networks regarding quality of service, pricing and other billing related features, in order to establish service agreement and get the authorization token. The paper provides better performance to check the revocation status of the mobile user using recency evidence compare to the previously used revocation list. Identity Based Signature is used to stop impersonation attack. The security and performance analysis indicates that our protocol is resistant to well-known attacks, and it ensures efficient roaming.