GSM security: a description of the reasons for security and the techniques

GSM is the 900 MHz radio system using a common world-wide standard. The system use by PCN (DCS 1800) is technically identical, except for the frequency. It allows full roaming from operator to operator if mutual bilateral agreements are in place. The objective of security for GSM system is to make the system as secure as the public switched telephone network. The use of radio at the transmission media allows a number of potential threads from eavesdropping the transmissions. It was soon apparent in the threat analysis that the weakest part of the system was the radio path, as this can be easily intercepted