Security Analysis of LTE Access Network

The latest technological development in mobile telecommunications is the 4G architecture. Developed and standardized by the 3GPP, this technology proposes significant throughput and security enhancements in comparison with its predecessor, 3G - a 3GPP architecture, as well as with the non-3GPP solutions like WiMAX. Besides the enhancements mentioned above, 4G is a simplified network architecture, flat-IP topology and services-oriented. One of the major simplifications is the base-station architecture, called eNodeB in the 4G terminology, which eliminates the need for a radio resource controller and assumes signaling, control-plane and security functions. It is the mobile device connection to the network and the proxy of all its traffic. This is why the access network is one of the most important areas for network design and optimization and also for security in term of access control, authentication, authorization and accounting. This paper reviews the access network components, the eNodeB security requirements, as defined by 3GPP and analyzes two secure access mechanisms to a 4G network, one via eNB (3GPP access type) and the other one via AP (non-3GPP access type). It also proposes an improvement to the AKA protocol in order to obtain better security.