Understanding Mobile Terms - Part 4

in Mobile Help

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; a refinement of FSK which minimises adjacent channel interference

GPRS
General Packet Radio Service; standardised as part of GSM Phase 2+, GPRS represents the first implementation of packet switching within GSM, which is a circuit switched technology. GPRS offers theoretical data speeds of up to 115kbit/s using multi slot techniques. GPRS is an essential precursor for 3G as it introduces the packet switched core required for UMTS

GPS
Global Positioning System; a location system based on a constellation of US Department of Defense satellites. Depending on the number of satellites visible to the user can provide accuracies down to tens of metres. Now being incorporated as a key feature in an increasing number of handsets

GRX
GPRS Roaming Exchange

GSM
Global System for Mobile communications, the second generation digital technology originally developed for Europe but which now has in excess of 71 per cent of the world market. Initially developed for operation in the 900MHz band and subsequently modified for the 850, 1800 and 1900MHz bands. GSM originally stood for Groupe Speciale Mobile, the CEPT committee which began the GSM standardisation process

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

Handoff
The transfer of control of a cellular phone call in progress from one cell to another, without any discontinuity

Hands-free
The operation of a cellular phone without using the handset; usually installed in vehicles.

HCS
Hierarchical Cell Structure; the architecture of a multi-layered cellular network where subscribers are handed over from the macro to the micro to the pico layer depending on the current network capacity and the needs of the subscriber

HDLC
High level Data Link Control

HIPERLAN
High Performance Radio Local Access Network; a wireless local area network being standardised by ETSI (Also HIPERLAN2)

HLR
Home Location Register; the database within a GSM network which stores all the subscriber data. An important element in the roaming process

HSCSD
High Speed Circuit Switched Data; a special mode in GSM networks which provides higher data throughput By concatenating a number of timeslots, each delivering 14.4kbit/s, much higher data speeds can be achieved

HSPSD
High Speed Packet Switched Data
The interface between the Node B and the RNC in a UMTS network

Iur
The interface between RNCs in a UMTS network

Iups
The connection between the RNC and the packet switched network in a GSM/GPRS/UMTS network

Iucs
The connection between the RNC and the circuit switched network in a GSM/GPRS/
UMTS network

I-ETS
Interim European Telecommunications Standard

I-mode
A service developed by Japanese operator NTT DoCoMo, I-mode delivers a huge range of services to subscribers and has proved enormously popular with some 30 million regular users. The revenue sharing model used for I-mode is being adopted by other operators as the basis for the new services enabled by GPRS and 3G

IMEI
International Mobile Equipment Identity

IMSI
International Mobile Subscriber Identity; an internal subscriber identity used only by the network

IMT-2000
The family of third generation technologies approved by the ITU. There are five members of the family: IMT-DS, a direct sequence WCDMA FDD solution IMT-TC, a WCDMA TDD solution IMT-MC, a multi carrier solution developed from cdma2000 IMT-SC, a single carrier solution developed from IS-136/UWC-136 IMT-FT, a TDMA/TDD solution derived from DECT

IN
Intelligent Network

INAP
Intelligent Network Application Part

Internet
A loose confederation of autonomous databases and networks. Originally developed for academic use the Internet is now a global structure of millions of sites accessible by anyone

Intranet
A private network which utilises the same techniques as the Internet but is accessible only by authorised users