- Cellular digital packet data
Developed in the early 1990s, CDPD was large on the horizon as a future technology. However, it had difficulty competing against existing slower but less expensive
Mobitexand DataTacsystems, and never quite gained widespread acceptance before newer, faster standards such as GPRSbecame dominant.
CDPD had very limited consumer offerings.
AT&T Wirelessfirst offered the technology in the United States under the PocketNet brand. It was one of the first consumer offerings of wireless web service. A company named Omnisky provided service for Palm V devices. Cingular Wireless later offered CDPD under the Wireless Internet brand (not to be confused with Wireless Internet Express, their brand for GPRS/EDGE data). PocketNet was generally considered a failure with competition from 2G services such as Sprint's Wireless Web. After the four phones AT&T Wireless had offered to the public (two from Panasonic, one from Mitsubishi and the Ericsson R289LX), AT&T Wireless eventually refused to activate the devices.
Despite its limited success as a consumer offering, CDPD was adopted in a number of enterprise and government networks. It was particularly popular as a first-generation wireless data solution for
telemetrydevices (machine to machine communications) and for public safety mobile data terminals.
In 2004, major carriers in the
United Statesannounced plans to shut down CDPD service. In July 2005, the AT&T Wirelessand Cingular WirelessCDPD networks were shut down.
* [http://www.cio.com/archive/060197/et.html CIO CDPD article]
* [http://www.emory.edu/BUSINESS/et/cdpd/ History and Development]
* [http://webmasters-forums.com/showthread.php?tid=393 Detailed Description About CDPD]
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