The name, General Packet Radio Service (GPRS) doesn't convey much information to the non-technical user. Describing it as providing a direct link into the Internet from a GSM phone, is much clearer. GPRS is to mobile networks what ADSL (Asymmetric Digital Subscriber Line) is to fixed telephone networks - the favoured solution for providing fast and inexpensive Internet links.
GPRS will undoubtedly speed up a handset's Internet connection - but it remains to be seen exactly how much speed can be wrung out of the system. GPRS works by amalgamating (aggregating) a number of separate data channels. This is feasible because data is being broken down into small 'packets' which are re-assembled by the receiving handset back into their original format. The catch is that the number of receiving channels does not necessarily have to match the number of sending channels. On the Internet, it is assumed that you want to view more information (such as a complicated Web page) than you want to send (such as a simple Yes or No response). So GPRS is an asymmetric technology because the number of ‘down’ channels used to receive data doesn’t match the number of ‘up’ channels used to send data.
The task of defining GPRS has been the responsibility of the Special Mobile Group (SMG) - part of the 3GPP initiative (3rd Generation Partnership Project). Rather than wait for the final version of the SMG standard some manufacturers decided to go with GPRS handsets which conformed to an earlier version of the specifications known as SMG29. This basically offers two 'down' channels and a single 'up' channel. In practice each channel is offering around 12-13 Kbit/s so the top speeds works out to be around 26 Kbit/s. Most experts agree, however that full interoperability between products will come with SMG 31. This is capable of offering four 'down' channels which equates to a top speed of around 52 Kbit/s - the same as a high speed (V.90) landline modem.
GPRS is classified as a 2.5G (or 2G Plus) technology because it builds upon existing network infrastructure whereas with 3G networks it normally requires building an entirely new network. In order to compete against 3G networks, therefore, North- American operators have been looking to GPRS to provide high speed data links. Hence, manufacturers have been working on a related technology known as EDGE (Enhanced Data for Global Evolution). In order to compete with 3G, EDGE must offer links running at 384 Kbit/s and originally this equated to running GPRS three times faster. However, because GPRS has proved much slower than expected, it now needs to be seven times faster.