Wireshark · Wireshark-users: Re: [Wireshark-users] about the VOIP bandwidth

[Jaap Keuter <jaap.keuter@xxxxxxxxx>]

On Sun, 30 Jan 2011 22:21:56 +0100, Anders Broman wrote:

>  nangergong skrev 2011-01-30 20:12:
> > Hi, all:
> >
> >    I'm using wireshark to capture VOIP streams, the Codec used in       the VOIP session is G711, which uses bandwidth of 64kbps. 
> >
> >    When I follow the following steps to analyse the VOIP streams:
> >
> >    Telephony->RTP->show all streams->Analyze,
> >
> >    I found that the IP BW (bandwidth) column shows that the       bandwidth is about 81.6 kbps.   I also used a traffic monitoring       program to monitor the traffic, which shows the bandwidth used is       about 64kbps (conformant to G711 bit rate ). So, I wonder whether       wireshark is accurate in measuring the bandwidth? or even other       metrics such as jitter,etc..
> >
> >    Thank you!
> The codec data inside the RTP is 64Kbit/s with RTP/UDP/IP/Ethernet     headers the rate should be something like 96Kb/s, if memory serves.
>  /Anders

It all depends on the protocol layer you look at. This site lets you have a good insight in what's involved here.

Thanks,
Jaap