Wireshark-users: Re: [Wireshark-users] Bandwidth calculation

From: "Anders Broman" <a.broman@xxxxxxxxx>
Date: Mon, 8 Mar 2010 19:36:37 +0100


The required bandwidth depends on the picture size and the frame rate.

See ITU H.263. If you have the SDP information setting up the video call there should be some information there

In respect to level , bit rate etc. Picture size may be indicated SQCIF QSIF CIF or inferred from the level.


The RTP Analysis is designed with voice in mind, time stamps and marker bit is used differently in

Voice and video I think. For video the marker bit is set for the last packet belonging to the same

Picture and the timestamp will be the same for all packets making up one picture (if memory serves).








Från: wireshark-users-bounces@xxxxxxxxxxxxx [mailto:wireshark-users-bounces@xxxxxxxxxxxxx] För Salvatore Frandina
Skickat: den 8 mars 2010 18:01
Till: wireshark-users@xxxxxxxxxxxxx
Ämne: [Wireshark-users] Bandwidth calculation



I'm using Wireshark to calculate the bandwidth of SIP based videoconference. I use Wireshark 1.2.6 rev 31702 on Windows vista 32 bit sp2 with eyebeam, pangolin and ekiga softphone. I use h263p video codec.
I have the problem with RTP statistics. Telephony->RTP->Show all streams->analyze->save as CSV.

I have noticed very strange behavior of bandwidth: the h263p codec with ekiga and pangolin requires about 100 kbit/s while with eyebeam about 300 kbit/s. Eyebeam has a little screen respect of ekiga or pangolin.

In the CSV file in eighth column (status) there are a lot of "incorrect timestamp". Could it be the cause of problem?

Sorry for my poor english




Salvatore Frandina
website: http://frandinas.altervista.org
mail: salvatore.frandina@xxxxxxxxx