[e2e] Reacting to corruption based loss

[Detlef Bosau]

Wesley Eddy weddy at grc.nasa.gov 
Tue Jun 7 04:18:09 PDT 2005 

> This idea is sort of discussed in the ETEN paper Craig sent a link to
> earlier.  One approach that it describes (CETEN_A) adapts beta between
> 1/2 and 1 based on the rate of congestion events reported.  In the
> October 2004 CCR, there is a paper that goes into greater depth on
> CETEN; "New Techniques for Making Transport Protocols Robust to
> Corruption-Based Loss" by Eddy, Ostermann, and Allman.

I see the point. But one question remains (admittedly, I did not yet
read the paper, therefore I apologize if you have given the answer
there).

How do you achieve _fairness_, when beta may vary?

AIMD results in fair shares, if alpha and beta are identical in 
competing flows. 
If beta is constantly chosen 1/2 and alpha derived from RTT (the idea
behind the formula alpha=MSS*MSS/CWND is to increase CWND by one MSS per
RTT, IIRC), which should be identical for competing flows, i.e. flows
sharing the same path, this is no problem. If alpha and / or beta are
different in competing flows,
to my understanding CWND generally will not reach the fair share.

Do you achieve similar values for beta in competing flows?

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Detlef Bosau
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