GlobalSystemForMobileCommunication is better known as '''GSM'''. You probably have a MobilePhone based on this. The alternative of CDMA appear to be still very much restricted to Bell related ventures.

In theory a "roaming service" allows you to travel all over the world with a single MobilePhone. In practice this is only recently feasible (if you exclude Japan and South Korea), due to variances in frequencies used.

See http://www.gsmworld.com/roaming/gsminfo/index.shtml for roaming and coverage (include satellite).

see also CodeDivisionMultipleAccess (CDMA)

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CategoryCommunicationProtocol CategoryWireless