GPRS FAQ
Before 3G, mobile operators using GSM technology for their cellular networks first introduced widespread data services through a technology called GPRS, short for General Packet Radio Service. The technology is typically referred to as a 2.5G service, as it builds upon the standards introduced in 2G GSM telephony. As well as being available to users of 2G networks, 3G-enabled networks can fall back on GPRS if the 3G network itself fails for whatever reason.
Definition
GPRS refers to the technologies of second generation GSM data, a worldwide standard in wireless technology. Wireless Internet, multimedia messaging and wireless software applications all make use of this technology to pass data to a GPRS-enabled cell phone. The technology is a precursor to EDGE, a faster (yet still second generation) data technology and so-called 3G services.
Speeds
Speeds of GPRS connections can be up to 115 kilobytes per second in lab environments. In real-world situations, however, data speeds to the consumer average around 30 to 40 kilobytes per second. Typically this is too slow for any type of streaming media, however is sufficient for most basic web browsing activities. In comparison, EDGE data rates are about 135 kilobytes per second, and 3G between 1.8 and 7.2 megabytes per second, again with the caveat that real-world conditions are slower.
Hardware Types
GPRS hardware falls into three different classes: A, B, and C. Most GPRS devices in useare Class B, which allows for use of the voice or data portion of the service at the same type. For example, when a voice call is received with Class B devices, the data channel is suspended and cannot be used until it ends. Class A devices will allow for voice and data to be used simultaneously, and Class C devices are like Class B devices, however the end user must manually switch the device between the voice and data channel.
Considerations
With the slowness of GPRS by nature, its usage is limited compared with faster technologies. During the height of the technology's use by GSM operators in the early part of this decade, web pages intended for mobile devices typically were of text only with limited graphical embellishments. While a GPRS connection can certainly load normal webpages, the speeds combined with latency issues will run load times for most pages to a minute or more. This most certainly makes mobile usage of streaming media difficult if not impossible.
Warning
GPRS connections are not without their problems. One of the most typical problems with data connections with this technology is latency, or the amount of time it takes for a data packets to make the trip between the sender and recipient. Latency rates of around 1 second do occur, and is most noticed by the user in the delay for the desired data to load, typically at the beginning of the connection. These problems are much less noticeable in EDGE and 3G connections.
Tags: Class devices, kilobytes second, voice data, data channel, generation data, GPRS connections