From owner-freebsd-ipfw@FreeBSD.ORG Mon Jan 3 18:46:20 2011 Return-Path: Delivered-To: freebsd-ipfw@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 54FEE106564A for ; Mon, 3 Jan 2011 18:46:20 +0000 (UTC) (envelope-from nangergong@gmail.com) Received: from mail-bw0-f54.google.com (mail-bw0-f54.google.com [209.85.214.54]) by mx1.freebsd.org (Postfix) with ESMTP id D8F348FC15 for ; Mon, 3 Jan 2011 18:46:19 +0000 (UTC) Received: by bwz12 with SMTP id 12so6560206bwz.13 for ; Mon, 03 Jan 2011 10:46:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:date:message-id :subject:from:to:content-type; bh=bRDsLR9RVMrAE3WghGQrIIi3S/KKteFKA9mVXEfj1s4=; b=sc3u5/3HK9be6v/j4S4deZOF21Tm3dsaPod4/z9PM+aY0d9AzoMOEKm/ALcejfMK9k nniprYNWvRXfLcRiXFLPzWp88LhbS+oebblsPjvaGMfQpOuROUgKYE/U3Ih+il/CKG63 9msFnHi8JUXwq3EeksGXYKQWA6QQg2NhRIMzs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=O2+iIqNOiim70aPqD4MXQcEST4+iRBma8ABmJ213T9D0ZU+Mzc0uAxwAUiAHlLX2ru X84/JD/Lwa0LCUCIv0rIDe+sRfPeRcKUzGc9oo0jjz+84K0ZfIRC762PVcw58jB8Ub5z pc7jY+42NkMZwr+Jw9ed3iAeTz7e5cbHDhXIw= MIME-Version: 1.0 Received: by 10.204.119.200 with SMTP id a8mr2541166bkr.152.1294078974922; Mon, 03 Jan 2011 10:22:54 -0800 (PST) Received: by 10.204.102.14 with HTTP; Mon, 3 Jan 2011 10:22:54 -0800 (PST) Date: Mon, 3 Jan 2011 18:22:54 +0000 Message-ID: From: nangergong To: freebsd-ipfw@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: How to obtain fixed packet loss ? X-BeenThere: freebsd-ipfw@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: IPFW Technical Discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 03 Jan 2011 18:46:20 -0000 Hi, all: As far as I know, in dummynet, plr is prabability-based, namely, when a packet is processed, it will be discarded according to the probability. So, if I have 100 packets and the plr is 5%, eventually I may just discard 3 packets or even 1 packets. So, the real packet loss is not consitent with the plr-set value. Is there any good method that can give me a consistent packet loss? Thank you!