GSM GPRS
General Packet Radio Service (GPRS) is a mobile data service available to users of GSM mobile phones. It is often described as "2. 5G", that is, a technology between the second (2G) and third (3G) generations of mobile telephony. It provides moderate speed data transfer, by using unused TDMA channels in the GSM network. Originally there was some thought to extend GPRS to cover other standards, but instead those networks are being converted to use the GSM standard, so that is the only kind of network where GPRS is in use. GPRS Platform. GPRS is integrated into GSM standards releases starting with Release 97 and onwards. First it was standardized by ETSI but now that effort has been handed onto the 3GPP.
GPRS basics
GPRS is different from the older Circuit Switched Data (or CSD) connection included in GSM standards released before Release 97 (from 1997, the year the standard was feature frozen). In CSD, a data connection establishes a circuit, and reserves the full bandwidth of that circuit during the lifetime of the connection. GPRS is packet-switched which means that multiple users share the same transmission channel, only transmitting when they have data to send. GSM's new GPRS (General Packet Radio Services) data transmission technology is
optimized for "bursty" datacom services such as wireless Internet/intranet.