A New Provably-Secure Key Agreement Protocol for Roaming in Mobile Networks

Protocols for authentication and key establishment have special requirements in a wireless environment. This paper presents a new key agreement protocol HAKA (home server aided key agreement) for roaming scenario. It is carried out by a mobile user and a foreign server with the aid of a home server,which provides all necessary authentications of the three parties. The session key can be obtained by no one except for the mobile user and the foreign server. HAKA is based on Diffie-Hellman key exchange and a secure hash function without using any asymmetric encryption. The protocol is proved secure in Canetti-Krawczyk (CK) model.