Preface

Wireless networking technology has shown an explosive growth worldwide over the past few years, bucking the general downward economic trend in the telecommunications industry. What is it about wireless networking that makes it so alluring on a grand scale? Why did over 22 million Wi-Fi devices ship last year, with double that projected by some for this year? While marketing folk might tell you that the particular feature set and brand name of their product is driving demand, I believe the answer is much simpler: it's magic.

Right where you are sitting now, there could be dozens of wireless data networks slinging information to the far corners of the Earth. A neighbor orders food online while someone across the street is using voice chat to talk to relatives (for free!) in Hong Kong, all the while someone upstairs is downloading a new album from their favorite band's web site in San Francisco. The information flows all around you (and, indeed, even through you) without you seeing or hearing a thing. Make no mistake, wireless networking is probably the second most magical technology on the planet just behind the Internet.

In hundreds of cities around the world, wireless networks are making ubiquitous connectivity more the rule than the exception, providing service (often free) to millions of users who suddenly need nothing more than a laptop and wireless card to get online. Wireless networking is getting people connected to each other more cheaply and easily than any other networking technology since the telephone.