End-to-end security for GSM users [speech coding method]

Mobile telecommunications such as GSM are now well established globally and users rely heavily on the convenient communications it provides. The level of security provided by GSM is superior to its predecessors and is more than adequate for the majority of users. However, some users in the areas of government, defence or business require additional security over and above that provided by the GSM standards and by standard GSM equipment. In a GSM network, only the radio channels between the mobile station (MS) and the base transceiver station (BTS) are encrypted. This paper presents the feasible methodology for implementation of end-to-end security over the available GSM infrastructure.