From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gregory Maxwell Date: Sun, 25 Mar 2001 06:59:25 +0000 Subject: Re: [LARTC] How to measure jitter & packet loss? Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lartc@vger.kernel.org On Sun, Mar 25, 2001 at 12:33:20PM +0800, Rick Goh wrote: > Inter-packet gaps if too big may cause real-time application to have > jitters. But how do i measure the jitter if supposedly i send out a tcp/udp > stream?? > > Attached is an extract of tcpdump data. > > Any information on how to post-analyse tcpdump for jitter, packet loss is > very very much appreciated. The text format isn't very useful for me. :) Tcpdump binary would be much better. What I normally do is a binary capture set to only grab the flows I'm interested in (i.e. no spurious arp activity like your dump), then I run the binary output back through tcpdump with it set to delta time mode once for each flow with the right filters to isolate the flow. Then I can import the resulting data into R (a freesoftware statistics package) where I can see and analyze the delay characterize of the flow. It's also useful to gather the same data on the transmit side and see how the statistics differ. _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://ds9a.nl/2.4Routing/