netdev - Re: [PATCH] make _minimum_ TCP retransmission timeout configurable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 29 Aug 2007 19:44:23 -0400
From:	John Heffner <jheffner@....edu>
To:	David Miller <davem@...emloft.net>
CC:	rick.jones2@...com, ian.mcdonald@...di.co.nz,
	netdev@...r.kernel.org, ilpo.jarvinen@...sinki.fi
Subject: Re: [PATCH] make _minimum_ TCP retransmission timeout configurable

David Miller wrote:
> From: Rick Jones <rick.jones2@...com>
> Date: Wed, 29 Aug 2007 16:06:27 -0700
> 
>> I belive the biggest component comes from link-layer retransmissions. 
>> There can also be some short outtages thanks to signal blocking, 
>> tunnels, people with big hats and whatnot that the link-layer 
>> retransmissions are trying to address.  The three seconds seems to be a 
>> value that gives the certainty that 99 times out of 10 the segment was 
>> indeed lost.
>>
>> The trace I've been sent shows clean RTTs ranging from ~200 milliseconds 
>> to ~7000 milliseconds.
> 
> Thanks for the info.
> 
> It's pretty easy to generate examples where we might have some sockets
> talking over interfaces on such a network and others which are not.
> Therefore, if we do this, a per-route metric is probably the best bet.

This is exactly what I was thinking.  It might even help discourage 
users from playing with this setting who should not. ;)

   -John
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html