MANUAL TEST FUNCTIONS
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Here is a screen shot of a capture collecting PC traffic that has a lot of YouTube downloads
running, but there is no VoIP traffic. This is evident by the fact that the Frequency graph is very
erratic. There is no fundamental frequency and there are no repeating harmonics.
Here are two screen shots of what it looks like to have VoIP on a mirrored port. Remember, a
mirrored port on one device will show both inbound and outbound traffic. Meaning, it will
include both the Tx audio and the Rx audio. The screen shot on the left shows the two 33Hz
streams, and the resultant Frequency graph due to rate of the two streams not exactly in phase
at exactly 33Hz. The screen shot on the right shows the individual selected 33Hz stream. Notice
the difference in the two frequency graphs. Neither should be relied on to determine solely if it
is VoIP, but both are indicative of needing further investigation.
