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<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">When I’ve been debugging RTP streams in Wireshark, I’ve noticed that Whireshark will get “everything wrong” when the timestamp changes (is reset). For instance, if I call a conference, by the
time I get into the conference, the RTP timestamps will start over, and FS will send the marker bit By that time Wireshark will report strange figures for jitter etc.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">After some Googling I’ve found that the meaning of the RTP marker is to indicate “the beginning of a talkspurt”. Which is not very clear to me... :)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">So my question is – is RTP marker really enough when starting a “new RTP stream” (not really new, but since the timestamps are reset we can think of it like that) – according to what I’ve been
able to find, maybe the SSRC should also be changed?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">I have created a patch that will change the SSRC when a reset like this occurs, and after that Wireshark detects my audio streams without problems (though, it will detect more streams), but no
strange jitter figures etc. are reported.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">The reason I started digging into this was because a PBX I was connecting to lost about the first second of audio after connecting to the conference, after also changing the SSRC the problem seems
resolved.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">I could make a RTP_BUG setting for this, but I’m not really sure if I should really care – that’s why I’m asking here, if anyone has more knowledge about this?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt">/Peter<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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