What is a GSM

What is a GSM
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GSM (Global System for Mobile Communications universal Mobile telecommunications System), is an open, evolving the improved System. This system is one of the advantages of the strongest in having the function of international roaming, consumers can with a number, in more than 159 countries don't accept all of the same quality blocked telephone service.
GSM standards will continue to improve the evolution, and radio, satellite and mobile system to provide more sharply with the service, including high speed multimedia data service, the service for synchronization using a built-in support, and will the Internet and fixed network perfect union.