GSM stands for GLOBAL system for mobile communication. it is used widely in Europe and other parts of the world.GSM was introduced in 1991 and its service was available in more than 100 countries and has become factual custom in Europe and Asia.GSM uses narrowband TDMA allowing eight simultaneous calls on the same radio frequency.
GSM is a digital mobile telephone system which digitizes and condenses data and operates inthe 900MHz, 1800MHz, or 1900MHz frequency bands. GSM has over one billion users worldwide and is now available in 190 countries. GSM network operators have roaming agreements and can use their mobile phones when they travel to other countries also. The purpose of this gateway is to raise awareness of these issues with GSM security.