Toward a Ubiquitous Mobile Access Model: A Roaming Agreement-Less Approach

The development in mobile devices and wireless technologies opens up unlimited choices of mobile services such as mobile commerce. These advances make access services available and convenient everywhere at any time. Since mobile users usually move, accessing services becomes unavailable especially in some locations that are not covered by their home networks. Therefore, it becomes necessary to roam into foreign networks in order to access such services. However, authenticating visiting users by a foreign network results in some security concerns. This challenge lies in the fact that a foreign network provider does not initially have the authentication credentials of the mobile users. The existing approaches are either roaming agreement-based in exchanging authentication information between the home network and a foreign network or vulnerable to some security attacks. This paper proposes a roaming agreement-less approach based on our ubiquitous mobile access model. This approach consists of two tokens: Passport (identification token) and Visa (authorisation token) to provide a flexible authentication method for foreign network to authenticate mobile users. The security analysis indicates that our proposal is more secure and suitable for ubiquitous mobile communications specially in roaming agreement-less environment.