GSM stand for Global System for Mobile Communications, originally Groupe Special Mobile, is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second generation ( 2G) digital cellular networks used by mobile phones. GENERAL 2G Network GSM 850 / 900 / 1800 / 1900 - all models. It is the de facto global standard for mobile communications The GSM standard was developed as a replacement for first generation ( 1G) analog cellular networks, and originally described a digital, circuit- switched network optimized for full duplex voice telephony. This was expanded over time to include data communications, first by circuit-switched transport, then packet data transport via GPRS (General Packet Radio Services) and EDGE (Enhanced Data rates for GSM Evolution or EGPRS). Subsequently, the 3GPP developed third generation ( 3G). 3G Network HSDPA 850 / 900 / 1700 / 1900 / 2100 - A1533 (GSM), A1453 HSDPA 850 / 900 / 1900 / 2100 - A1457, A1530 UMTS standards followed by fourth generation (4G) LTE Advanced standards, which are not part of the ETSI GSM standard.
07:02, 12 July 2014
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