[89312] in North American Network Operators' Group
UDP Badness [Was: Re: How to measure network quality&performance for v
daemon@ATHENA.MIT.EDU (Fergie)
Tue Mar 7 12:18:49 2006
From: "Fergie" <fergdawg@netzero.net>
Date: Tue, 7 Mar 2006 17:15:46 GMT
To: gstammw@gmx.net
Cc: nanog@nanog.org
Errors-To: owner-nanog@merit.edu
The problem with UDP is that there is no explicit feedback-loop
or congestion control frobs -- this is generally kicked up the
protocol stack for the application itself to figure out.
UDP is designed that way: push traffic into the network as fast
as the network can take it, and expect the application to provide
for delay/loss/adaptation of jitter, buffering, etc.
So to answer your question, I think it really depends on how
the application itself handles UDP traffic, adapts to any sort
of RTT measurements, delay/jitter, etc.
- ferg
-- "Gunther Stammwitz" <gstammw@gmx.net> wrote:
Hello colleages,
I'm trying to find out how one can measure the performance or quality of=
a
network for gamers and voip-users.
Both applications are very sensitive to packetloss, delays or jitter sin=
ce
they're using udp instead of tcp and are very timing critical.
=3D=3D> Which tools (under linux) are you using in order to measure your=
own
network ore on of your upstreams in terms of "gameability" or voip-usage=
?
Ordinary pings won't help since routers are regulary dropping them and e=
ven
an end-to-end ping is not perfect since one of the hosts might be busy o=
r
something like that?
Starting your favorite online game and play on a server that is being ho=
used
in your own network isn't the solutions I'm looking for :-(
Your ideas are appreciated :-)
Gunther
--
"Fergie", a.k.a. Paul Ferguson
Engineering Architecture for the Internet
fergdawg@netzero.net or fergdawg@sbcglobal.net
ferg's tech blog: http://fergdawg.blogspot.com/
