Re: [tcpm] Tuning TCP parameters for the 21st century

Joe Touch <touch@ISI.EDU> Wed, 15 July 2009 16:21 UTC

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Date: Wed, 15 Jul 2009 09:19:24 -0700
From: Joe Touch <touch@ISI.EDU>
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Subject: Re: [tcpm] Tuning TCP parameters for the 21st century
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michawe@ifi.uio.no wrote:
...
>> useful to understand where the drops are and why. Retransmitting SYNs to
>> a busy endpoint whose queue is overflowing doesn't help things, e.g.
> 
> I understand that now, too (thanks to Lachlan who
> explained it to me), and hence apologize for having
> been ignorant to this rather obvious issue in the
> above paper.
> 
> - but what about retransmitting SYN/ACKs faster?
> Since the other side already sent a SYN, it probably
> isn't overloaded

That presumes the other side already sent a SYN and it's been received,
and that the SYN/ACK is what's getting lost/delayed/retransmitted.  If
not, that won't help.

First find where things are going wrong empirically ;-)

Joe
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