Wireless data networks exist in such number and variety as to be difficult to categorize and compare.
Some wireless data networks run over wireless voice networks, such as mobile telephone networks. CPDP, HSCSD, PDC-P, and GPRS are examples. Other wireless networks run on their own physical layer networks, utilizing anything from antennas built into handlheld devices to large antennas mounted on towers. 802.11, LMDS, and MMDS are examples. A few wireless networks are intended only to connect small devices over short distances. Bluetooth is an example.
Wireless networks which run over other wireless networks often utilize the lower layer networks to provide security and encryption. Stand-alone wireless networks either provide their own security and encryption features or rely upon VPN's (Virtual Private Networks) to provide those features. In many cases, multiple layers of security and encryption may be desirable.
Some wireless networks are fixed, meaning that antennas do not move frequently. Other wireless networks are mobile, meaning that the antenna can move constantly. This is sometimes a feature of the specific implementation and antenna design, instead of an inherent limitation of the wireless network specification.
Wireless networks may operate on licensed or unlicensed portions of the frequency spectrum.
Common Wireless Network Types
Major types of wireless networks include:
CDPD.........Cellular Digital Packet Data
HSCSD.......High Speed Circuit Switched Data
PDC-P........Packet Data Cellular
GPRS.........General Packet Radio Service
1xRTT........1x Radio Transmission Technology
MMDS........Multichannel Multipoint Distribution Service
LMDS.........Local Multipoint Distribution Service
WiMAX.......Worldwide Interoperability for Microwave Access
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