UDP vs. TCP distribution [was: Re: [e2e] Can feedback be generated...]

[Sally Floyd]

>I'd venture a guess that
>most of this is RealMedia/QuickTime/Windows Media Player.  

The packet traces from the MAWI Working Group Traffic Archive at
"http://tracer.csl.sony.co.jp/mawi/" break down the udp traffic
into dns, rip, realaud, halflif, everque, quake, and other.  E.g.,
"http://tracer.csl.sony.co.jp/mawi/samplepoint-B/2001/200102251400.html".
For the days that I looked, the UDP traffic on this transoceanic
link was dominated by DNS, actually.  But maybe transoceanic links 
have different traffic mixes than other ones.

>Those
>should use fairly well-defined congestion control mechanisms.  Is
>there any work on characterizing these kinds of transport protocols
>with respect to their levels of "TCP-friendliness"?

We have just started to look at this.  In addition to thinking some
about the potential fit of equation-based congestion control (e.g.,
TFRC) for these kinds of traffic.  It turns out that the deployment
of ECN in the Internet would add a new interest to some of these issues.

- Sally
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http://www.aciri.org/floyd/
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