Agilent Technologies 622Vu Advisor, User Manual

Page: 131 / 244

Chapter 8
Filtering Captures
When you capture incoming traffic, the capture files get large very quickly if you
keep every cell. Because of this, 622Vu Advisor lets you set up filters that
identify the characteristics of the cells you want to keep. When you initiate a
capture (see page 77), 622Vu Advisor lets you specify a filter to use to control
the content of the capture file. The filter you specify operates in real time during
the capture, at full bandwidth and at the hardware level.
1
You can define filtersets from three places: using 622Vu Advisor’s standard
filterset processing (described in this chapter), during capture processing
(described in Chapter 6), or while monitoring real-time statistics (described in
Chapter 7).
8.1 Understanding Filters
Filters are defined in terms of filtersets. Each capture
can use, at most, one and only one filterset. The image
to the right shows six filtersets. At the highest level,
each filterset is defined as either capturing everything
(i.e., all traffic), or as using filter entries. The specifics of the filterset definition
vary depending on the type of filterset (everything or use filter entries).
Each filterset divides the memory available for capturing cells into receive areas
(called filter buffers), and specifies what type(s) of cells should go into each
area:
•
For filtersets that are defined as capturing everything, there’s only one buffer,
called CaptureAll.
1 This contrasts with the subset facility described in Chapter 6, which lets you reduce the cells
in a capture after the full capture has taken place. The filtering capability provides a more
efficient way to limit the content of the capture, for those situations where you’ll never need
the cells being eliminated.
8: Filtering Captures
8.1 Understanding Filters
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