Re: [Ethereal-users] Decoding RTP?

[Guy Harris <guy@xxxxxxxxxx>]

> Will Ethereal be able to dissect this setup?  (At least the RTP
> fixed header part).  I remember seeing some discussion on the mailing
> list that Ethereal could only dissect RTP if it was accompanied
> by RTSP or RTCP control messages.

It can only *recognize* RTP if it somehow knows which traffic is RTP;
RTP doesn't have a standard port number and there's no heuristic I know
of that works for it, so those mechanisms won't do it.

One way of doing that is if it sees, in the capture, an RTSP (not RTCP)
message specifying that some conversation will be using RTP.

Another way of doing that, in the current CVS-tree version of Ethereal,
is for the user to tell it that some particular port is to be dissected
as RTP, using the "Tools->Decode As.." or right-mouse-button-menu "Decode
As..." dialog box.