netdev - Re: [PATCH net-next] tcp: Add TCP

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 linux-cve-announce 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]

Message-ID: <CAPh34mdeYib4VSDT7Fj9i-oNc4c8HmUGT9KHpU2gS4scpODdpA@mail.gmail.com>
Date:	Fri, 24 Oct 2014 18:26:07 +0200
From:	Hagen Paul Pfeifer <hagen@...u.net>
To:	Yuchung Cheng <ycheng@...gle.com>
Cc:	Kristian Evensen <kristian.evensen@...il.com>,
	David Miller <davem@...emloft.net>,
	Network Development <netdev@...r.kernel.org>
Subject: Re: [PATCH net-next] tcp: Add TCP_FREEZE socket option

On 24 October 2014 16:58, Yuchung Cheng <ycheng@...gle.com> wrote:

> Do packets actually get dropped during the handover period? if not
> then the sender can detect spurious RTOs and undo the cwnd reductions
> with timestamps or DSACKs (Eifel). Eifel did not exist when the
> freeze-TCP was published at 2000. Even if the connection does not
> support these options as major TCP stacks do, slow-start on a path
> with new BDP isn't that bad of an idea.

Yes, starting with fresh values for a new links is a good thing to do.
But what I think what Kristian want to address is to reduce larger
idle period due to backoff'ing timeouts followed by larger idle
periods? E.g. like a temporary cork for an exact period of time.

I thought that freeze-TCP was *also* designed to bridge a larger
disconnection? The downside with this approach (compared to SplitTCP)
is that you only send one instance into sleep. The other peer (sender)
may run into timeouts too.

Hagen
--
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