[e2e] Latency Variation and Contention.

[Detlef Bosau]

Sireen Habib Malik wrote:
> 
> Hi,
> 
> Have not read the paper, however, I think that if,
> 
> RTT = Round Trip Time, and
> dRTT = variations in RTT,
> 
> then "dRTT" is a weak/poor indicator of congestion.
> 
> A congestion signal based upon "dRTT/RTT" would give a much better idea,
> relatively speaking.

Hm. At least, it looks more complex ;-)

However, it does not really affect the "hi-lo-quest". 

As far as I see, the basic question is: Can we detect / react upon
network congestion by latency observation?

It is no big deal whether we look at the RTT or variance. We can even
look at higher moments of RTT (skewness, curtosis), we can introduce
quantiles and thresholds, we can use any formula TeX is able to print
:-) 

The question is: Can we distinguish a loaded network from an unloaded
one by (pure) latency observation / evaluation.

Detlef



> 
> --
> Sireen
> 


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