Introduction
Forward
Data communication networks are, at their most fundamental level, the
exchange of bits, grouped into units and sub-units, and exchanged in
accordance with a predefined set of rules we call protocols.
Understanding the operation of any data communication system may be
decomposed into understanding the bits, the units, and the protocols.
Troubleshooting, optimizing, and securing a network is accomplished
by comparing and contrasting the observed behavior of these bits and
data units with the established protocol rules, restrictions, and capacity
requirements. The process of observing the internal operations in a
communication network is the process of "protocol analysis", and, in
the realm of the IEEE 802.11 wireless LAN (WLAN) standards, that's
what this book is all about.
My first exposure to WLAN technology was through the draft 802.11
standards document from the Institute of Electrical and Electronics
Engineers (IEEE). The 802.11b draft standards soon followed, and
were ratified in the second half of 1999. Since there were few practical
implementations of the 802.11 standard it was too early to know what
was going to be important, what was going to be found to be flawed,
and what would never be widely implemented. Those of us in the RF
engineering space watched this new "wireless LAN" technology
explode into the marketplace with unprecedented growth. Today you
have the benefit of the past five years of industry experience with
802.11 technology, and The CWAP Study Guide has distilled key
concepts and facts into a very readable volume. You're not going to be
struggling to understand a sometimes seemingly cryptic IEEE standard.
You're going to learn how this new, pivotal technology works and how
you can confirm its efficiency, security, and correct operation. You're
going to be able to demonstrate your knowledge and expertise through
professional certification in the Certified Wireless Network
Professional (CWNP
®
) program, the accepted industry standard for
802.11 engineering expertise.
When we consider the bits in a WLAN, we're thinking in terms of the
binary 1's and 0's that are represented by the wiggling and jiggling of
electromagnetic energy transmitted through space. There are many
