From owner-freebsd-net Mon Apr 3 2:50:20 2000 Delivered-To: freebsd-net@freebsd.org Received: from storm.FreeBSD.org.uk (storm.freebsd.org.uk [194.242.139.170]) by hub.freebsd.org (Postfix) with ESMTP id A2DD537BD81 for ; Mon, 3 Apr 2000 02:50:13 -0700 (PDT) (envelope-from brian@Awfulhak.org) Received: from hak.lan.Awfulhak.org (hak.nat.Awfulhak.org [172.31.0.12]) by storm.FreeBSD.org.uk (8.9.3/8.9.3) with ESMTP id KAA34155; Mon, 3 Apr 2000 10:50:07 +0100 (BST) (envelope-from brian@Awfulhak.org) Received: from hak.lan.Awfulhak.org (localhost [127.0.0.1]) by hak.lan.Awfulhak.org (8.9.3/8.9.3) with ESMTP id KAA01581; Mon, 3 Apr 2000 10:50:03 +0100 (BST) (envelope-from brian@hak.lan.Awfulhak.org) Message-Id: <200004030950.KAA01581@hak.lan.Awfulhak.org> X-Mailer: exmh version 2.1.1 10/15/1999 To: "Ari Suutari" Cc: "Arun Sharma" , freebsd-net@FreeBSD.ORG, brian@hak.lan.Awfulhak.org Subject: Re: kernel vs user level implementation of NAT In-Reply-To: Message from "Ari Suutari" of "Mon, 03 Apr 2000 09:24:02 +0300." <006401bf9d35$37bddb00$0e05a8c0@intranet.syncrontech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 03 Apr 2000 10:50:02 +0100 From: Brian Somers Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > Hi, > > > > Can someone point me to some discussion or literature on why *BSDs chose > > to implement natd as a daemon as opposed to a kernel service ? I'm > > particularly interested in the performance (latency) aspects of the issue. > > > > The history goes something like this: > > Some years ago I had a cable modem connection at home. I had > internal network with some hosts and a FreeBSD server machine > (running 2.x if I remember correctly). I was looking for solutions how > to get my internal machines to access internet with similar > manner as ip masquerading in Linux (Couldn't use Linux, I'v > always been fond of *BSD). > > Well, I found that Darren Reed's ipfilter didn't work with 2.x so > that was out. Porting of it looked like too much effort at that time. > > Then I found out from somewhere that user mode ppp had > nat features and took a look at it. Surprisingly all the functions > necessary to do it were packaged to a few source files > which I took into natd. These sources were written by Charles > Mott and eventually ended into libalias library. > > There was also another similar program in the beginning, > Brian Somer's masqd. I don't remeber any more why I decided > to go along with natd - maybe both were at very early stage of > development > and I just had more time to play with natd. Anyway, Brian also > contributed to natd. I found out about natd around 2 days after starting masqd, so I dropped it :*] > What I found good about doing this in user process was the > ease of debugging and testing of new versions. > > Ari S. -- Brian Don't _EVER_ lose your sense of humour ! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message