From mboxrd@z Thu Jan  1 00:00:00 1970
From: tsuna <tsunanet@gmail.com>
Subject: Re: [PATCH] tcp: Implement a two-level initial RTO as per draft RFC 2988bis-02.
Date: Thu, 19 May 2011 00:07:09 -0700
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Cc: David Miller <davem@davemloft.net>, kuznet@ms2.inr.ac.ru,
	pekkas@netcore.fi, jmorris@namei.org, yoshfuji@linux-ipv6.org,
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To: Alexander Zimmermann <alexander.zimmermann@comsys.rwth-aachen.de>
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On Wed, May 18, 2011 at 11:52 PM, Alexander Zimmermann
<alexander.zimmermann@comsys.rwth-aachen.de> wrote:
>> So we're talking about a [200ms ; 120s] range no matter what.
>
> Why is 200ms a valid lower bound for initRTO? I'm aware of
> measurements that 1s is save for Internet, but I don't know of any
> studies that 200ms is save...

The constants that are quoted aren't specific to the initRTO.  They're
used to bound the RTO as it gets adjusted during the TCP session.  See
`tcp_set_rto' in tcp_input.c for reference.

-- 
Benoit "tsuna" Sigoure
Software Engineer @ www.StumbleUpon.com