Abstract: Security problems in interworking networks have attracted much attention of researchers recently. The typical interworking networks can be constructed with the core network WCDMA and the accessing networks WiMAX and WLAN. Considering security and efficiency issues,a roaming authentication protocol based on symmetric cryptographic algorithms was proposed for that network. It verified the identity of wireless access networks to prevent the redirection attack, and used the localized authentication mechanism to reduce the message transmission delay and improve the efficiency of rcauthentication process. The efficiency of proposed protocol was simulated in NS2. By analyzing the security of the proposed protocol with universally composable(UC)modcl, it proves that the proposed protocol satisfies the definition of UC security defined in the UC model.

Key words: Wireless network, Authentication protocol, Session key, Roaming