The First Bit

Wireless communications today span a wide range of different technologies, includin g cellular, Personal Communications Service (PCS), satellite, infrared, wireless data WANs, specialized mobile radio, and wireless LANs. A previous online chapter, Wide Area Wireless WANs , discussed wireless wide area networks, including cellular, PCS, CDPD, RAM Mobile Data, ARDIS, Metricom Ricochet, paging and satellite communications. In this chapter we shorten our sights to concentrate on local area networks.

Wireless LAN technology today is relatively mature, though its adoption has not always met vendors' expectations. Nevertheless, wireless LANs are becoming commonplace in applications such as health care, trading floors, supermarkets, transportation and warehousing and are increasingly being used in office environments. Meanwhile the number of vendors keeps increasing, the technology keeps getting better and less expensive, and with the recently completed IEEE 802.11 standard, interoperability between vendors is becoming less of an issue. Moreover, convenient form factors such as PC Cards are becoming common. You may be surprised at how easy wireless LANs are to use and deploy, and how cost effective they are compared to wired LANs, which have many indirect and hidden costs associated with installation and reconfigurations.

Wireless LAN hardware costs more than wired LAN hardware and throughput is usually slower. But the technology allows us to set up networks in hard-to-wire places such as historic buildings or in temporary circumstances such as at trade shows and to support technology workers who need to be mobile. Many wireless LAN vendors also offer products that can bridge networks together as an alternative to leased line connections (though that is not our focus here).

Wireless LANs are fundamentally different from their wide area cousins. They differ in performance, usage, type of spectrum and in their connection with existing networks. Explaining why is one of our first topics as we examine the types of wireless LANs. We then drill into the various aspects of how wireless LANs work so you understand how to purchase and deploy them. We explain how to configure network software and applications, we discuss future trends in the industry, and we end with a useful table of vendor information. Our table of contents is:

• Types of Wireless LANs
• Understanding Wireless LANs
• Making Network Software and Applications Work
• Propagating Into the Future
• Vendor Information

Peter Rysavy is the president of Rysavy & Associates, a consulting firm that works with both companies developing new communications technologies and those adopting them. He can be reached at rysavy@rysavy.com or http://www.rysavy.com/rysavy .

Updated January 14, 1998