Case Studies
have contacted an analyst, Mr. Parsons, to determine the root cause of
the problem(s).
Mr. Parsons begins by placing an analyzer close to the access point. He
notices that Donohue’s access point is using channel 11, the RF
medium is not very busy, and a relatively low amount of frames are
being transmitted even during the busiest part of the work day. Figure
13.6 illustrates the low RF medium usage.
FIGURE 13.6
Low RF utilization
Next, Mr. Parsons notices that the number of retransmissions is
abnormally high, considering that “normal” is less than 3% and “high”
is around 10% on average. The reason for the retransmissions is that
many frames are being corrupted. Figure 13.7 illustrates an analyzer
displaying retransmission percentages.
