The Evolution of the GSM Network
The existing mobile digital communications network continues to
develop, in order to increase capacity, coverage, quality and
data transmission rates. There have been a series of developments
that are now starting to be deployed with the aim of enhancing
the GSM network functionality.
The next section shows the enhancements
planned for the next few years, starting off with High Speed Circuit
Switched Data (HSCD). The next development is General Packet Radio
Services (GPRS), this is a packet-switched service that allows
full mobility and wide-area coverage. Enhanced Data rates for
GSM Evolution (EDGE) will use enhanced modulation and related
techniques, further improving local mobility. Universal Mobile
Telecommunications System (UMTS) will include second and third
generation services.

Figure 18 Evolution of GSM Data Service
(Adapted from Ericsson Document EN/LZT 123 5374 R1B)