Global System for Mobile Communications (GSM)

Originally the GSM is stand for Groupe Spécial Mobile. Global Systems for Mobile communication is an international standard which are the only type of cellular service available in Europa and also others parts of the world. GSM is a leading digital cellular systems, it was introduce to replace the First generation (1G) analog cellular networks. It use narrowband Time Division Multiple Access (TDMA) which allows 8 simultaneous calls on the same radio frequency. Europe and Asia is using 900MHz band to operate and United States is operate the GSM in 1900MHz. The growth of GSM make the acronym is changing to Global System for Mobile Communications.


Features of GSM:

• Encryption that make phone calls more secure
• Data networking
• Group III facsimile Services
• Short Message Service (SMS)
• Call forwarding
• Caller Id
• Call waiting
• Multi-party conferencing

History of GSM

• 1982, Conference of European Post and Telegraphs (CEPT) formed a group call GSM to research the merits of a European standard for mobile telecommunications.
• 1991, Commercial GSM is being introduced
• End of year 1997, GSM service was available in more than 100 countries and become the de facto standard in Europe and Asia.

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