GSM or Global System for Mobile Communications or Group Special Mobile can be described as a standard which specially developed for 2G cellular networks. It was developed first on 1st July 1991, while Harri Holkeri, Finnish Prime Minister, made the world’s first GSM call to Kaarina Suonio, Mayou of Tampare. But now the technology has become 20 years old.

Early European analog cellular networks adopt this technologies as well as protocol which varied from country to country by preventing the interoperability of the subscriber equipment and additionally by increasing complexity for equipment manufactures.

GSM was first adopted as a standard digital mobile technology in the year of 1987, while 15 representatives of 13 European countries had signed a memorandum of understanding for developing or deploying a common cellular phone system across all over the continent. Eventually, the Phase 1 of the GSM specification was published in the year of 1990.

GSM was specially developed as a substitute for first generation analog cellular network service. So, the standard of GSM originally a digital circuit switch network in order to optimized full duplex voice telephony. But time has passed, so now it is quite being able to transport the packed data via GPRS. Though on the later part the packet data transmission speed were increased via EDGE. Now one new version of GSM technology has successfully developed by 3GPP i.e. 3G UMTS. Moreover, all GSM networks are currently working on introducing 4G LTE Advanced standards.

High quality voice calls, international roaming and support, text messaging system or SMS, Multimedia Messaging System or MMS of GSM has now create a big boon in worldwide mobile phone use. The more good news is that it has now adopted by the all countries in the universe. So in a sentence GSM has become the most ubiquitous standard for cellular network.