Global System for Mobile communications
(GSM: originally from Group Special Mobile) is the most popular
standard
for mobile phones in the world. Its promoter, the GSM Association,
estimates that 82% of the global mobile market uses the standard GSM is used by
over 2 billion people across more than 212 countries and territories. Its
ubiquity makes international roaming very common between mobile phone operators,
enabling subscribers to use their phones in many parts of the world. GSM
differs from its predecessors in that both signaling and speech channels are digital
call quality, and so is considered a second generation (2G) mobile phone
system. This has also meant that data communication were built into the system
using the 3rd Generation Partnership Project (3GPP)The GSM logo is used to
identify
compatible handsets and equipment
The key
advantage of GSM systems to consumers has been better voice quality
and low-cost alternatives to making calls, such as the Short message service
(SMS, also called "text messaging"). The advantage for network
operators has been the ease of deploying equipment from any vendors that
implement the standard. Like other cellular standards, GSM allows network
operators to offer roaming services so that subscribers can use their phones on
GSM networks all over the world.
Newer versions of the standard were backward-compatible with the original
GSM phones. For example, Release ''97 of the standard added packet data
capabilities, by means of General Packet Radio Service (GPRS). Release ''99
introduced higher speed data transmission using Enhanced Data Rates for GSM
Evolution (EDGE).