ng several circuit channels GPRS to provide packet radio access to external packet data networks (such as X.25 or Internet) Enhanced Data rate for GSM Evolution (EDGE) using a new modulation scheme to provide up to three times higher throughput (for HSCSD and GPRS) Universal Mobile Telecommunication System (UMTS), a new wireless technology using new infrastructure deployment These extensions enable Higher data throughput Better spectral efficiency Lower call setup times The way to implement GPRS is to add new packet data nodes in GSM/TDMA networks and upgrade existing nodes to provide a routing 2 Mbps Figure 2-9 Steps of 1 Mbps 100 Kbps 64 Kbps Circuit HSCSD 10 Kbps 1 Kbps Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. GPRS Introduction GPRS Introduction path for packet data between the mobile terminal and a gateway node. The gateway node will provide interworking with external packet data net- works for access to the Internet and intranets, for example. Few or no hard- ware upgrades are needed in existing GSM/TDMA nodes, and the same transmission links will be used between Base Transceiver Stations and Base Station Controllers for both GSM/TDMA and GPRS. GPRS Roaming At the end of June 2001, 551 million GSM customers were on record and 447 operators in 170 countries have now adopted GSM. The expectation is that GSM growth will continue and it will have 700 million GSM customers by June 2002. As the growth continues and more people disconnect from their wired phones, GSM will have 800 million customers by the end of 2003 and 1 billion customers by 2005. Obviously, this places a lot of growth on the providers' networks and puts more demand on the ability to use the service wherever and whenever we want. GSM Voice Roaming was a 15 bil- lion Euro business in 1999, thus indicating that the masses are using their phones today in a roaming manner