Wireshark-users: Re: [Wireshark-users] RTP Stream Analyses [Marker Bit]

From: "Shuaib Siddiqui" <shuaibe@xxxxxxxxx>
Date: Thu, 12 Jul 2007 14:37:38 +0200
Hi,
 
Looks like i didnt get the messages ... sorry about that.
 
@ Lars:
"The wrong jitter values probably come from the fact that there is no (or at least not the right) sampling clock rate defined for the used payload type." I didnt understand what you mean, who and where we have to define the sampling clock rate or how can we fix this ?

thanks!


 
 
From: "Lars Ruoff" <lars.ruoff@xxxxxxxxxxxxxxxxx>
Date: Fri, 6 Jul 2007 16:40:29 +0200

 
From my memories:
packets with the marker bit set don't take part in the jitter calculation.
This is because in RTP audio streams marked packets usually mark the end of silence periods.
The wrong jitter values probably come from the fact that there is no (or at least not the right) sampling clock rate defined for the used payload type.
Both issues would be worth revisiting.
 
Lars


On 7/12/07, Lars Ruoff <lars.ruoff@xxxxxxxxxxxxxxxxx> wrote:
There were some responses to your mail!
As long as you aren't registered, look at the web archives at http://www.wireshark.org/lists/wireshark-users/
 
Lars
 


From: wireshark-users-bounces@xxxxxxxxxxxxx [mailto: wireshark-users-bounces@xxxxxxxxxxxxx] On Behalf Of Shuaib Siddiqui
Sent: jeudi 12 juillet 2007 12:58
To: wireshark-users@xxxxxxxxxxxxx
Subject: [Wireshark-users] RTP Stream Analyses [Marker Bit]

 
Hi,

I streaming videos using VLC on the client side and Darwin Streaming Server on server side. When I analyse the rtp stream on the client side using Wireshark, I see some RTP with marker bit set and immediately after such RTP packet the jitter value is very high as compared to the previous one, plus it also displays Incorrect Timestamp. I looked up the marker bit in the RFC 1889 but they just state it as profile specific. Kindly, can anyone provide any further explanation?
Plus does the abnormality in the jitter value means the jitter values further on are not credible ?
Thank you for yout time!

Shuaib
 
PS: I have asked this question before but didnt get any explanation, so I would kindly request all the users and the Wireshark Gurus to give some insight into this problem, thank you!



--
MSc in Communication Systems
I&C Faculty
EPFL
Switzerland
Home page: http://shuaibe.googlepages.com/