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T.38 packet loss in Graph Analysis?

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Hi,

I’m having a trace of a Fax call using T.38. When I look at the packets I don’t see anything wrong. I found a match when I searched for the subject below, however there’s no answer to this issue. https://supportforums.cisco.com/discussion/12440601/spa122-t38-fails-some-lines

In the Graph Analysis there something like Duration: 46.56s Pack lost, Pack burst lost 90 When I check the timestamp, there is nothing special that can be observed in the T.38 framing.

Can somebody explain what this means. The issue in this case is that for a fax one end is sending and somewhere at the half at the page (judging the timestamps of the error in the flow graph) there is suddently a packet lost indication? The sequence numbers in the file is correct there is no packet loss at the UDP level. What does this packet loss mean that is only visable in the graph flow? As this packet loss appears in the sending direction, what does it mean, did the sender make errors on the T.38 level?

Thanks!

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asked 13 Dec '16, 01:16

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MarcelV
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