From owner-freebsd-net@FreeBSD.ORG  Mon Mar 23 10:44:32 2009
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 8B1A11065670
	for <freebsd-net@freebsd.org>; Mon, 23 Mar 2009 10:44:32 +0000 (UTC)
	(envelope-from b93502044@ntu.edu.tw)
Received: from wmail1.cc.ntu.edu.tw (wmail1.cc.ntu.edu.tw [140.112.2.161])
	by mx1.freebsd.org (Postfix) with ESMTP id 59A958FC17
	for <freebsd-net@freebsd.org>; Mon, 23 Mar 2009 10:44:32 +0000 (UTC)
	(envelope-from b93502044@ntu.edu.tw)
Received: from localhost (localhost [127.0.0.1])
	by wmail1.cc.ntu.edu.tw (Postfix) with ESMTP id A13E61F4C27
	for <freebsd-net@freebsd.org>; Mon, 23 Mar 2009 18:20:21 +0800 (CST)
Received: from newreno.ee.ntu.edu.tw (newreno.ee.ntu.edu.tw
	[140.112.42.102]) by wmail1.cc.ntu.edu.tw (Horde MIME library) with
	HTTP; Mon, 23 Mar 2009 18:20:21 +0800
Message-ID: <20090323182021.ysrn0ogu84cg084g@wmail1.cc.ntu.edu.tw>
Date: Mon, 23 Mar 2009 18:20:21 +0800
From: Andrew Chen <b93502044@ntu.edu.tw>
To: freebsd-net@freebsd.org
MIME-Version: 1.0
Content-Type: text/plain;
	charset=BIG5;
	DelSp="Yes";
	format="flowed"
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable
User-Agent: Internet Messaging Program (IMP) H3 (4.1.5)
Subject: Problems in using SCTP CMT
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/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: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 23 Mar 2009 10:44:32 -0000

Hi,
=09We have some problems when we tried to send data using CMT-SCTP. =20
Actually, we are not sure if we do enable CMT functionalities. We set =20
up two PCs with FreeBSD-7.0. Each PC has two NICs and two IPs. One is =20
public and the other is private. We wrote simple FTP server and client =20
programs. On both sides, local addresses are bound as INADDR_ANY. =20
According to =20
http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-14#section-4.1.5
, if we bind INADDR_ANY and then call connect(), the multi-homing =20
capability of SCTP is automatically enabled. Further, we also turn on =20
sysctl states by setting
sysctl net.inet.sctp.cmt_pf=3D1
sysctl net.inet.sctp.cmt_use_dac=3D1
sysctl net.inet.sctp.cmt_on_off=3D1
=09Then we start transmission and capture the traffics. Unfortunately, =20
the captured packet shows data were transmitted on primary path and =20
there were only heartbeat/HB ACKs on the other path.
=09To our knowledge, to use CMT, the only things we have to do is to =20
establish a multihomed association, and turn on the sysctl options.
=09Can anyone point out something we did wrong or steps we missed?
=09Thanks in advance.