Secure application access to IMS via 4G GAA architecture

The entire telecommunications and services world has focused its attention on the newest 3GPP architecture, 4G. Proposing high speed data transfer, all flat-IP network for the core systems and stronger authentication and AAA methods, this architecture seems to be the answer for the mobile networks of the future. Another architecture described by 3GPP as well, but based on IETF standards is the IMS architecture. This is focused on mobile services, mainly VoIP, but also presence, push-to-talk, location and multimedia and broadcast services. The IMS core network has its own security mechanisms, which are constantly tested and improved. Looking in the perspective, the user equipment, specially the one found in roaming has to do a lot of signaling in order to authenticate to both networks and use the services available for it in a secure manner. From the provider's point of view, the issue is even more complicated, because it has to secure its network, securely interoperate with other networks, be able to obtain granular charging information and also provide lawful interception capabilities for the government institutions. This paper reviews the authentication security architecture available in 3GPP for providing secure access to application services, with emphasis on the interaction of 4G and IMS components, being the first step in a larger 4G-IMS interaction study with regards to security.