GSM (Global System for Mobile communications) is an open, digital cellular technology used for transmitting mobile voice and data services.
GSM supports voice calls and data transfer speeds of up to 9.6 kbps, together with the transmission of SMS (Short Message Service).
GSM operates in the 900MHz and 1.8GHz bands in Europe and the 1.9GHz and 850MHz bands in the US. GSM services are also transmitted via 850MHz spectrum in Australia, Canada and many Latin American countries. The use of harmonised spectrum across most of the globe, combined with GSM’s international roaming capability, allows travellers to access the same mobile services at home and abroad. GSM enables individuals to be reached via the same mobile number in up to 219 countries.
Terrestrial GSM networks now cover more than 90% of the world’s population. GSM satellite roaming has also extended service access to areas where terrestrial coverage is not available.