From owner-freebsd-net Thu May 3 1:15:39 2001 Delivered-To: freebsd-net@freebsd.org Received: from elvis.mu.org (elvis.mu.org [216.33.66.196]) by hub.freebsd.org (Postfix) with ESMTP id 25EF537B423 for ; Thu, 3 May 2001 01:15:37 -0700 (PDT) (envelope-from billf@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1098) id B2E9881D05; Thu, 3 May 2001 03:15:36 -0500 (CDT) Date: Thu, 3 May 2001 03:15:36 -0500 From: Bill Fumerola To: Luigi Rizzo Cc: Gunther Schadow , Darren Reed , thorpej@zembu.com, snap-users@kame.net, julian@elischer.org, freebsd-net@freebsd.org, ipfilter@coombs.anu.edu.au, altq@csl.sony.co.jp Subject: Re: [altq 838] Re: The future of ALTQ, IPsec & IPFILTER playing together ... Message-ID: <20010503031536.H75584@elvis.mu.org> References: <3AF108F2.BA4AF637@aurora.regenstrief.org> <200105030750.JAA44246@info.iet.unipi.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <200105030750.JAA44246@info.iet.unipi.it>; from luigi@info.iet.unipi.it on Thu, May 03, 2001 at 09:50:25AM +0200 X-Operating-System: FreeBSD 4.3-FEARSOME-20010328 i386 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Thu, May 03, 2001 at 09:50:25AM +0200, Luigi Rizzo wrote: > wrong. It is an interpreted bytecode, much slower than, > say, approaches which translate individual filters into > native machine code (DPT/DPF ? don't remember the exact reference, > it was some usenix/sigcomm paper). http://www.pdos.lcs.mit.edu/~engler/dpf.html > > and that BPF scales very well for even complex > > expressions. > > this is more a ruleset compiler issue, where you try to analyse > the whole ruleset and find out what are the important > field to look at, build a tree/trie to drive your > searches, use lookup and hash tables, etc.e tc. -- there is a lot of > recent literature on the topic of fast packet classification. yeah, someone should write an ipfw compiler. :-> -- Bill Fumerola - security yahoo / Yahoo! inc. - fumerola@yahoo-inc.com / billf@FreeBSD.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message