Introduction to Wireless LAN Analysis
As a result, companies must periodically perform security assessments
to ensure that all security policies are being met. Performing a manual
security walk-through on a regular basis is incredibly time-consuming,
so administrators should consider automated, distributed systems such
as a wireless LAN IDS. Automated systems with fixed policies are less
likely to make mistakes than administrators performing manual scans.
Troubleshooting
Even well-designed wireless LANs will eventually have trouble
meeting the needs of users. For example, spotty coverage can crop up
after an incomplete, inaccurate, or poorly done site survey or when
changes are made to the facility. If proactive analysis is not done
regularly, then users will ultimately complain about coverage issues.
Or, defective access point firmware may disallow some users from
associating. This problem would also prompt users to complain to the
help desk. Support staff must then reactively troubleshoot the problems
and define a solution. As the wireless LAN administrator, you can
analyze before the problem occurs and prevent it, or you can analyze
after the end-users have become frustrated and start complaining.
Wireless LAN Analysis Tools
There are several types of tools available that aid in the analysis of
wireless LANs, including protocol analyzers, RF analyzers, and
simulation tools.
Protocol Analyzers
A protocol analyzer, sometimes referred to as a packet analyzer, is the
primary tool for analyzing the protocols of wireless LANs. In general,
protocol analyzers focus on measuring and displaying 802.11 MAC
Layer frames, fields, and parameters (see Figure 1.1). However, many
of the protocol analyzers also implement some basic form of RF signal
measurement, such as signal amplitude, noise amplitude and channel
number (see Figure 1.2). The protocol analyzer is an invaluable tool
for the wireless LAN analyst.
