From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeffrey Laramie Subject: Re: NAT, MANGLE, and TOS Date: Thu, 23 Oct 2003 14:22:46 -0400 Sender: netfilter-admin@lists.netfilter.org Message-ID: <3F981C76.9020407@Loudoun-Fairfax.com> References: <20031023175634.87744.qmail@web40201.mail.yahoo.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20031023175634.87744.qmail@web40201.mail.yahoo.com> Errors-To: netfilter-admin@lists.netfilter.org List-Help: List-Post: List-Subscribe: , List-Id: List-Unsubscribe: , List-Archive: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: nf SBlaze wrote: >Currently I run a very and common setup for my home network. > >My Linux box acts as my router and gateway for my home network and simply NATs >everything out to the cable modem and onto the internet. > >My question is this. I have read awhile ago that changing the TOS of packets >can be beneficial in ganing small performance. Logically I thought this would >pretty much be limited to a Point to Point systems. However by posting to some >forums for broadband, i hearf through the perverbial grapevine that my >ISP(Charter Communications) will honor user or application set TOS values >unless they are under network congestion. I can of course not verify this. > >This is my quandry. Currently this is all I do.. > >iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to 68.119.49.97 > >Is it possible to mangle NAT in a way that all my nat traffic carries slightly >higher TOS values? Will this give me a slight to any boost in upstream? > >As always thanks for any info in advance and hail to the open source community. >SBlaze > > You can use the appropriately named mangle table to set TOS like this: $iptables -t mangle -A OUTPUT -p tcp -m state --state NEW,RELATED,ESTABLISHED -m tcp --sport 80 -j TOS --set-tos 0x08 I don't have enough traffic on my network to see a noticeable difference when I change TOS, but given your situation, setting TOS might help. Jeff