ABSTRACT
The desire to communicate quickly and reliably with our family, friends, and colleagues is one of the
most widespread of human needs, and wireless telephony has exploded in the last decade as a ubiquitous
tool to fulfill that desire. Over 400 million cellular handsets were sold in the years 2002 and 2003, and the
market is expected to grow to nearly a billion phones per year within the next decade. At the same time,
the market for the now-ubiquitous wireless local area network 802.11a/b/g is expected to exceed 100
million per year. The cellular telephone and wireless LAN card have become so common and wide-
spread, such an integral part of modern existence, that it is easy to forget that they were considered to be
expensive novelties just 15 years ago.
