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GSM (Global System for Mobile Communications, originally ''Groupe Spécial Mobile''), is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile phones, first deployed in Finland in July 1991.〔Anton A. Huurdeman, (The Worldwide History of Telecommunications ), John Wiley & Sons, 31 juli 2003, page 529〕 it has become the default global standard for mobile communications - with over 90% market share, operating in over 219 countries and territories.〔(【引用サイトリンク】title=GSM Global system for Mobile Communications )〕 2G networks developed as a replacement for first generation (1G) analog cellular networks, and the GSM standard originally described a digital, circuit-switched network optimized for full duplex voice telephony. This expanded over time to include data communications, first by circuit-switched transport, then by 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) UMTS standards followed by fourth-generation (4G) LTE Advanced standards, which do not form part of the ETSI GSM standard. "GSM" is a trademark owned by the GSM Association. It may also refer to the (initially) most common voice codec used, Full Rate. == History == In 1982, work began to develop a European standard for digital cellular voice telephony when the European Conference of Postal and Telecommunications Administrations (CEPT) created the Groupe Spécial Mobile committee and later provided a permanent technical support group based in Paris. Five years later, in 1987, 15 representatives from 13 European countries signed a memorandum of understanding in Copenhagen to develop and deploy a common cellular telephone system across Europe, and EU rules were passed to make GSM a mandatory standard.〔(EU Seeks To End Mandatory GSM for 900Mhz - Source )〕 The decision to develop a continental standard eventually resulted in a unified, open, standard-based network which was larger than that in the United States. In 1987 Europe produced the very first agreed GSM Technical Specification in February. Ministers from the four big EU countries cemented their political support for GSM with the Bonn Declaration on Global Information Networks in May and the GSM MoU was tabled for signature in September. The MoU drew-in mobile operators from across Europe to pledge to invest in new GSM networks to an ambitious common date. It got GSM up and running fast. In this short 37-week period the whole of Europe (countries and industries) had been brought behind GSM in a rare unity and speed guided by four public officials Armin Silberhorn (Germany), Stephen Temple (UK), Philippe Dupuis (France), and Renzo Failli (Italy). In 1989, the Groupe Spécial Mobile committee was transferred from CEPT to the European Telecommunications Standards Institute (ETSI).〔〔〔〔 In parallel, France and Germany signed a joint development agreement in 1984 and were joined by Italy and the UK in 1986. In 1986 the European Commission proposed reserving the 900 MHz spectrum band for GSM. The world's first GSM call was made by the former Finnish prime minister Harri Holkeri to Kaarina Suonio (mayor in city of Tampere) on July 1, 1991, on a network built by Telenokia and Siemens and operated by Radiolinja. The following year in 1992, the first short messaging service (SMS or "text message") message was sent and Vodafone UK and Telecom Finland signed the first international roaming agreement. Work began in 1991 to expand the GSM standard to the 1800 MHz frequency band and the first 1800 MHz network became operational in the UK by 1993. Also that year, Telecom Australia became the first network operator to deploy a GSM network outside Europe and the first practical hand-held GSM mobile phone became available. In 1995, fax, data and SMS messaging services were launched commercially, the first 1900 MHz GSM network became operational in the United States and GSM subscribers worldwide exceeded 10 million. Also this year, the GSM Association was formed. Pre-paid GSM SIM cards were launched in 1996 and worldwide GSM subscribers passed 100 million in 1998.〔 In 2000, the first commercial GPRS services were launched and the first GPRS compatible handsets became available for sale. In 2001 the first UMTS (W-CDMA) network was launched, a 3G technology that is not part of GSM. Worldwide GSM subscribers exceeded 500 million. In 2002 the first Multimedia Messaging Service (MMS) were introduced and the first GSM network in the 800 MHz frequency band became operational. EDGE services first became operational in a network in 2003 and the number of worldwide GSM subscribers exceeded 1 billion in 2004.〔 By 2005, GSM networks accounted for more than 75% of the worldwide cellular network market, serving 1.5 billion subscribers. In 2005 the first HSDPA capable network also became operational. The first HSUPA network was launched in 2007. High-Speed Packet Access (HSPA) and its uplink and downlink versions are 3G technologies, not part of GSM. Worldwide GSM subscribers exceeded three billion in 2008.〔 The GSM Association estimated in 2010 that technologies defined in the GSM standard serve 80% of the global mobile market, encompassing more than 5 billion people across more than 212 countries and territories, making GSM the most ubiquitous of the many standards for cellular networks. It is important to note that GSM is a second-generation (2G) standard employing Time-Division Multiple-Access (TDMA) spectrum-sharing, issued by the European Telecommunications Standards Institute (ETSI). The GSM standard does not include the 3G UMTS CDMA-based technology nor the 4G LTE OFDMA-based technology standards issued by the 3GPP.〔(【引用サイトリンク】url= http://www.etsi.org/technologies-clusters/technologies/mobile/gsm?highlight=YToxOntpOjA7czozOiJnc20iO30= )〕 Macau planned to phase out its 2G GSM networks as of June 4, 2015, making it the first region to decommission a GSM network.〔(【引用サイトリンク】title=3G Get Ready )〕 Singapore will also be phasing out 2G services by April 2017. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「GSM」の詳細全文を読む スポンサード リンク
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