G

Gc: The interface between the GGSN and the HLR in a GSM/GPRS network Gd: The interface between the SGSN and the SMSC in a GSM/GPRS network Gf: The interface between the SGSN and the EIR in a GSM/GPRS network Gi: The interface between the GGSN and the Internet in a GPRS network Gn: The interface between the GGSN and the SGSN in a GPRS network Gp: The interfaces between the GGSN/SGSN and the Border Gateway in a GPRS network Gr: The interface between the SGSN and the HLR in a GPRS network Gs: The interface between the SGSN and the MSC in a GSM/GPRS network GAIT - GSM/ANSI 136 Interoperability Committee GAP - Generic Access Profile; a DECT term Gbit/s: A unit of data transmission rate equal to one billion bits per second GMSC - Gateway Mobile Services Switching Centre; the gateway between two networks GCF - Global Certification Forum Geostationary: Refers to a satellite in equatorial orbit above the earth which appears from the surface to be stationary GERAN - GSM-EDGE Radio Access Network the name for the evolution of GSM towards 3G based on EDGE GGRF - GSM Global Roaming Forum GGSN - Gateway GPRS Support Node; the gateway between a cellular network and a IP network. GHz: A unit of frequency equal to one billion Hertz per second GMPCS - Global Mobile Personal Communications by Satellite GMSK - Gaussian filtered Minimum Shift Keying GPRS: General Packet Radio Service (GPRS) is a mobile data service available to users of GSM and IS-136 mobile phones. GPRS data transfer is typically charged per megabyte of transferred data, while data communication via traditional circuit switching is billed per minute of connection time, independently of if the user actually has transferred data or been in an idle state. GPRS can be utilized for services such as WAP access, SMS and MMS, but also for Internet communication services such as email and web access. In the future, it is expected that low cost voice over IP will be made available in cell phones. GPS: The Global Positioning System (GPS), is currently the only fully-functional satellite navigation system. More than two dozen GPS satellites are in medium Earth orbit, transmitting signals allowing GPS receivers to determine the receiver's location, speed and direction. GRX - GPRS Roaming Exchange GSM The Global System for Mobile Communications, GSM (original acronym: Groupe Spécial Mobile) is the most popular standard for mobile phones in the world. GSM service is used by over 2 billion people across more than 212 countries and territories.[1][2] The ubiquity of the GSM standard makes international roaming very common between mobile phone operators, enabling subscribers to use their phones in many parts of the world. GSM differs significantly from its predecessors in that both signaling and speech channels are Digital call quality, which means that it is considered a second generation (2G) mobile phone system. This fact has also meant that data communication was built into the system from the 3rd Generation Partnership Project (3GPP). GSM MoU - The GSM Memorandum of Understanding (an agreement signed between all the major European operators to work together to promote GSM. The precursor of the GSM Association) GSM-R : GSM-Railway, A variant of GSM designed to meet the special communications needs of international train operators