From owner-freebsd-net@freebsd.org  Tue Jul 18 19:00:49 2017
Return-Path: <owner-freebsd-net@freebsd.org>
Delivered-To: freebsd-net@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id C911DD9DB41
 for <freebsd-net@mailman.ysv.freebsd.org>;
 Tue, 18 Jul 2017 19:00:49 +0000 (UTC)
 (envelope-from hiren@strugglingcoder.info)
Received: from mail.strugglingcoder.info (strugglingcoder.info
 [104.236.146.68])
 by mx1.freebsd.org (Postfix) with ESMTP id B3BB2803FC
 for <freebsd-net@freebsd.org>; Tue, 18 Jul 2017 19:00:49 +0000 (UTC)
 (envelope-from hiren@strugglingcoder.info)
Received: from localhost (unknown [10.1.1.3])
 (Authenticated sender: hiren@strugglingcoder.info)
 by mail.strugglingcoder.info (Postfix) with ESMTPA id 16D8C1775A;
 Tue, 18 Jul 2017 11:54:12 -0700 (PDT)
Date: Tue, 18 Jul 2017 11:54:11 -0700
From: hiren panchasara <hiren@strugglingcoder.info>
To: KVK Singh <krishnavijay@mnnit.ac.in>
Cc: freebsd-net@freebsd.org
Subject: Re: TCP Zero Window Advertisement.
Message-ID: <20170718185411.GA48940@strugglingcoder.info>
References: <CA+dH1tBpiTbrbWrS2BXnPb5a8_amHkPyst1GCfawdKOrTpp-kw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512;
 protocol="application/pgp-signature"; boundary="17pEHd4RhPHOinZp"
Content-Disposition: inline
In-Reply-To: <CA+dH1tBpiTbrbWrS2BXnPb5a8_amHkPyst1GCfawdKOrTpp-kw@mail.gmail.com>
User-Agent: Mutt/1.5.23 (2014-03-12)
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net/>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 18 Jul 2017 19:00:49 -0000


--17pEHd4RhPHOinZp
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On 07/18/17 at 11:28P, KVK Singh wrote:
> Hi,
>=20
> By going through the Zero Window advertisement concept What I found is th=
at
> if sender has transmitted packet 2,3,4,5,6,7  i.e packet from 2-7 total  6
> packets in flight then By chance if sender received a Zero Window
> Advertisement (ZWA) for segment 4 then it does not enters in probe
> mode/ persistent
> state. However if it receive ZWA for 7 i.e last packet in flight then it
> enters in Probe mode/ persistent state and it starts probing for window
> update.

Can you please site/explain how you got to this conclusion? Did you find
FreeBSD or any other implementation doing this?
>=20
> Is that the behavior is correct Because as going through the paper and RFC
> I find that any segment can be acked with ZWA and sender will enter in
> persist mode once it receive the ZWA.

I thought this is how its supposed to work. I may be mis-remembering.

Cheers,
Hiren

--17pEHd4RhPHOinZp
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=
=xgiw
-----END PGP SIGNATURE-----

--17pEHd4RhPHOinZp--