From owner-freebsd-ipfw@FreeBSD.ORG Mon May 9 17:17:31 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 74FCB106566C for ; Mon, 9 May 2011 17:17:31 +0000 (UTC) (envelope-from quamarniyaz.zhcet@gmail.com) Received: from mail-wy0-f182.google.com (mail-wy0-f182.google.com [74.125.82.182]) by mx1.freebsd.org (Postfix) with ESMTP id 087818FC0A for ; Mon, 9 May 2011 17:17:30 +0000 (UTC) Received: by wyf23 with SMTP id 23so5273173wyf.13 for ; Mon, 09 May 2011 10:17:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:date:message-id:subject:from:to :content-type; bh=ofLnrQNAjvvF3SOVKys0BI51kjX8uvBL60yvl5Ys4O0=; b=iO4kYRtd9PRb364aZdK6jlLd1Wepy7hcz3JWW/ZincNftjL0ND5IKO88gtxHMsueZk FR8orkxBaxfvS/N9EOZKtcjHEQDTxEMtbY4s3L7hrAH6DvlrnIDpmRQhJlsgqkUcboac Lu2kmMb8bzvLzRbg9mmZBVspdAfChAvfpkRAE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=ZsPwh37hvij43xRQSio2wa18sRLsUk6totLTfhAOI7AZ63jSWH1Ai/e+Ffu5WN3eIb 3J0C0xhzOnMhXvy6FMq+xMgLztNNBu1eLL0QMjsnn5FWqtW43UaFSlKSHJemjWvARzGo MG+QymMgLIh3AKbv1hggZJgGeo991ZBz4jZew= MIME-Version: 1.0 Received: by 10.216.188.20 with SMTP id z20mr5658139wem.66.1304959603613; Mon, 09 May 2011 09:46:43 -0700 (PDT) Received: by 10.216.175.206 with HTTP; Mon, 9 May 2011 09:46:43 -0700 (PDT) Date: Mon, 9 May 2011 22:16:43 +0530 Message-ID: From: quamar niyaz To: freebsd-ipfw@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: DummyNet configuration for opportunistic Links for emulating DTN 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, 09 May 2011 17:17:31 -0000 Hi, I am working on a application which is meant for Delay Tolerant Network. I want to emulate the opportunistic link availability for the data sending nodes using dummyNet . One scenario, suppose from source node to destination node let's say a data link is available at around 9 a.m. morning and the latency of the link from source node to destination node is 1hr. So if a request for upload comes around 8 a.m. at the sending node then the data should start reaching to the destination node after 10 a.m. as the link between the nodes comes at 9 and the latency is 1 hr so delivery time at the destination node(9 a.m. +1hr. = 10.am.). In other words sending node should hold the data in its buffer till 10 a.m as the nodes are actually in my 100 Mbps LAN so for emulating this the sender must start sending the data after 10 a.m. Can the buffer holds such large amount of data e.g. 500 MB for an hour. Or I have to modify the buffer size if yes, to which file i have to modify and then build dummynet. Or simply writing a batch scripts is fine for this. Please let me know. Thanks in advance -- With regards, Quamar Niyaz Research Associate, Indian Institute of Technology, Delhi New Delhi-16 http://www.cse.iitd.ernet.in/~niyaz