RTP identification/User Data in hex

[Desem, Can]

Sorry to send this again, but my subscription to the mailing list only finalised today (there was a delay in the authentication step). Therefore,  I did not see whether my mail got posted and whether there were any replies. If there were replies could you please forward it to me since the mail archive does not seem to be current.

Thanks,
Can Desem
Telstra Research Laboratories

>  -----Original Message-----
> From: 	Desem, Can  
> Sent:	Thursday, 10 April 2003 15:09
> To:	'argus-info at lists.andrew.cmu.edu'
> Subject:	RTP identification/User Data in hex
> 
> I have only recently started  using argus. It's quite an impressive piece or software!.
> 
> I find it quite useful that it can identify the rtp and rtcp flows though it does not seem to do this as effectively as I would have hoped. 
> I have been trying it on some Netmeeting generated flows. It can identify the udp audio streams as rtp but not the video streams. However, it can identify the two rtcp flows associated with the audio and the video streams.  My initial observation is that the differences between the audio and the video stream rtp packets are the payload type (4 : G.723 for audio, 34: H.263 for video), time stamps and the synchronisation source identifiers. Would these result in one being recognised while not the other, or are there other differences not immediately obvious.
> 
> However, given that there are two rtcp streams one can reasonably be confident that the udp stream  is really an rtp stream as well. And given that we can capture a number of data bytes, one can see whether it matches the RTP header and also what  payload type/codec is being used. But it seems that this is  not so easy given that data is only printed in ascii or endcode64. Is this correct or can we get a Hex dump of the data?
> 
> 
> Regards,
> Can Desem
> Telstra Research Laboratories
>  
>