Seamless interoperation of LTE-UMTS-GSM requires flawless UMTS and GSM

Though the mobile communication technology keep facilitating new generations such as LTE, UMTS, etc the replacement of the past generation technologies may take time and it may not be replaced in its entirety. Hence, interoperability among these technologies are coming into the picture. This interoperation may introduce unexpected security vulnerabilities which are inherited from the past generation technologies such as GSM. Moreover, most phones are programmed to gracefully fail over to GSM when a 3G/4G connection seems unavailable [13]. Hence, irrespective of the presence of advanced technologies, the interoperability demands to update the identified flaws of the past technologies. This will pave way for seamless secure communication through interoperation. Hence, in this paper, a HMAC based mutual authentication and key agreement protocol for GSM is proposed to avoid false base station attack. The correctness of the protocol is verified by using Proverif.