General Packet Radio Service
[1] Networks and mobile devices with GPRS started to roll out around the year 2001;[2] it offered, for the first time on GSM networks, seamless data transmission using packet data for an "always-on" connection (eliminating the need to "dial-up"),[3] so providing improved Internet access for web, email, WAP services, Multimedia Messaging Service (MMS) and others.
On the other hand, on GPRS networks, data is broken into small packets and transmitted through available channels.
GPRS was succeeded by EDGE ("2.75G") which provided improved performance and speeds on the 2G GSM system.
Depending on the device, location and intended use, regulations may be imposed either restricting or explicitly specifying authorised frequency bands.
There is a more comprehensive record of international cellular service frequency assignments GPRS supports the following protocols: When TCP/IP is used, each phone can have one or more IP addresses allocated.
To avoid this hardware requirement, a GPRS mobile device may implement the dual transfer mode (DTM) feature.
This is combined with time domain statistical multiplexing which makes it possible for several users to share the same frequency channel.
The down-link uses first-come first-served packet scheduling, while the up-link uses a scheme very similar to reservation ALOHA (R-ALOHA).
This means that slotted ALOHA (S-ALOHA) is used for reservation inquiries during a contention phase, and then the actual data is transferred using dynamic TDMA with first-come first-served.
Newer network equipment can adapt the transfer speed automatically depending on the mobile location.
In contrast to the shared nature of GPRS, these instead establish a dedicated circuit (usually billed per minute).
[18] Each multislot class identifies the following: The different multislot class specification is detailed in the Annex B of the 3GPP Technical Specification 45.002 (Multiplexing and multiple access on the radio path) The maximum speed of a GPRS connection offered in 2003 was similar to a modem connection in an analog wire telephone network, about 32–40 kbit/s, depending on the phone used.
With these enhancements the active round-trip time can be reduced, resulting in significant increase in application-level throughput speeds.
GPRS opened in 2000[20] as a packet-switched data service embedded in the channel-switched cellular radio network GSM.
[21][22] The CELLPAC[23] protocol developed 1991–1993 was the trigger point for starting in 1993 the specification of standard GPRS by ETSI SMG.
Especially, the CELLPAC Voice & Data functions introduced in a 1993 ETSI Workshop contribution[24] anticipate what was later known to be the roots of GPRS.
[25] Successor systems to GSM/GPRS like W-CDMA (UMTS) and LTE rely on key GPRS functions for mobile Internet access as introduced by CELLPAC.
It is a subset of General Packet Radio Service (GPRS) on the GSM network and improves upon it offering speeds close to 3G technology, hence the name 2.75G.
