Chapter 18, 802.11 on the Macintosh, describes how to use the AirPort card on MacOS X to connect
to 802.11 networks. It focuses on Mac OS X 10.3, which was the first software version to include
802.1X support.
Chapter 19, Using 802.11 on Linux, discusses how to install 802.11 support on a Linux system. After
discussing how to add PC Card support to the operating system, it shows how to use the wireless
extensions API. It discusses two common drivers, one for the older Orinoco 802.11b card, and the
MADwifi driver for newer cards based on chipsets from Atheros Communications. Finally, it shows
how to configure 802.1X security using xsupplicant.
Chapter 20, Using 802.11 Access Points, describes the equipment used on the infrastructure end of
802.11 networks. Commercial access point products have varying features. This chapter describes
the common features of access points, offers buying advice, and presents two practical configuration
examples.
Chapter 21, Logical Wireless Network Architecture, marks the third transition in the book, from the
implementation of 802.11 on the scale of an individual device, to how to build 802.11 networks on a
larger scale. There are several major styles that can be used to build the network, each with its
advantages and disadvantages. This chapter sorts through the common types of network topologies
and offers advice on selecting one.
Chapter 22, Security Architecture, should be read in tandem with the previous chapter. Maintaining
network security while offering network access on an open medium is a major challenge. Security
choices and architecture choices are mutually influential. This chapter addresses the major choices to
be made in designing a network: what type of authentication will be used and how it integrates with
existing user databases, how to encrypt traffic to keep it safe, and how to deal with unauthorized
access point deployment.
Chapter 23, Site Planning and Project Management, is the final component of the book for network
administrators. Designing a large-scale wireless network is difficult because there is great user
demand for access. Ensuring that the network has sufficient capacity to satisfy user demands in all
the locations where it will be used requires some planning. Choosing locations for access points
depends a great deal on the radio environment, and has traditionally been one of the most time-
consuming tasks in building a network.
Chapter 24, 802.11 Network Analysis, teaches administrators how to recognize what's going on with
their wireless LANs. Network analyzers have proven their worth time and time again on wired
networks. Wireless network analyzers are just as valuable a tool for 802.11 networks. This chapter
discusses how to use wireless network analyzers and what certain symptoms may indicate. It also
describes how to build an analyzer using Ethereal, and what to look for to troubleshoot common
problems.
Chapter 25, 802.11 Performance Tuning, describes how network administrators can increase
throughput. It begins by describing how to calculate overall throughput for payload data, and
common ways of increasing performance. In rare cases, it may make sense to change commonly
exposed 802.11 parameters.
Chapter 26, Conclusions and Predictions, summarizes current standards work in the 802.11 working
group. After summarizing the work in progress, I get to prognosticate and hope that I don't have to
revise this too extensively in future editions.
Major Changes from the First Edition
The three years between 2002 and 2005 saw a great deal of change in wireless LANs. The standards
themselves continued to evolve to provide greater security and interoperability. Following the typical