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Summary
Wireless connectivity is available at many levels. Personal networks can be established for communication between devices in close proximity to one another. These networks are most commonly used as a cable replacement technology. The leading technologies in this area are Bluetooth and 802.15. Moving to larger wireless networks, wireless local area networks can provide high-speed wireless coverage within 100 meters of a base station. These networks can be used to either replace wired networks or to extend them. The leading WLAN technologies include 802.11a, 802.11b, and HIPERLAN. Both of these network types operate over unlicensed frequencies so there is no charge or airtime.For wireless communication on a larger scale, wireless wide area networks are available. These networks are in their third generation, offering high-quality voice communication and high-speed data access on a national level. These networks extend enterprise systems into new locations. There are many competing standards for WWANs, including GSM, GPRS, cdmaOne, and WCDMA. If truly global wireless access is required, satellite networks are available to provide access to voice and data applications from anywhere on the planet.In the next chapter we will take an introductory look at the leading mobile application architectures.
