Wirelss Wide Area Network

Wirelss Wide Area Network A WWAN differs from a WLAN (wireless LAN) in that it uses Mobile telecommunication cellular network technologies such as WIMAX (though it's better applicated into WMAN Networks), UMTS, GPRS, CDMA2000, GSM, CDPD, Mobitex, HSDPA or 3G to transfer data. It can use also LMDS and Wi-Fi to connect to the Internet. These cellular technologies are offered regionally, nationwide, or even globally and are provided by a wireless service provider for a monthly usage fee.[1] WWAN connectivity allows a user with a laptop and a WWAN card to surf the web, check email, or connect to a Virtual Private Network (VPN) from anywhere within the regional boundaries of cellular service. Various computers now have integrated WWAN capabilities (Such as HSDPA in Centrino). This means that the system has a cellular radio (GSM/CDMA) built in, which allows the user to send and receive data. There are two basic means that a mobile network may use to transfer data:
Packet-switched Data Networks (GPRS/CDPD)
Circuit-switched dial-up connections
Since radio communications systems do not provide a physically secure connection path, WWANs typically incorporate encryption and authentication methods to make them more secure. Unfortunately some of the early GSM encryption techniques were flawed, and security experts have issued warnings that cellular communication, including WWANs, is no longer secure.[2] UMTS(3G) encryption was developed later and has yet to be broken.
Examples of providers for WWAN include Sprint Nextel, Verizon, and AT&T.