Re: [dtn] CRC discussion

"Marc Blanchet" <marc.blanchet@viagenie.ca> Fri, 04 October 2019 20:14 UTC

Return-Path: <marc.blanchet@viagenie.ca>
X-Original-To: dtn@ietfa.amsl.com
Delivered-To: dtn@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E45B6120090 for <dtn@ietfa.amsl.com>; Fri, 4 Oct 2019 13:14:24 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=viagenie-ca.20150623.gappssmtp.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Jmz7DTpcESDw for <dtn@ietfa.amsl.com>; Fri, 4 Oct 2019 13:14:23 -0700 (PDT)
Received: from mail-qk1-x733.google.com (mail-qk1-x733.google.com [IPv6:2607:f8b0:4864:20::733]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 0D2F612004A for <dtn@ietf.org>; Fri, 4 Oct 2019 13:14:22 -0700 (PDT)
Received: by mail-qk1-x733.google.com with SMTP id f16so6960960qkl.9 for <dtn@ietf.org>; Fri, 04 Oct 2019 13:14:22 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=viagenie-ca.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ry1lUwCqAfBgfWSwubKT+DxUza2U0Nz1qiU4D2SgsSU=; b=bzWCMAVeiCB0KPvtgC39uLn7HSNymkEYs512l5ADW0O05k1BpEn8RYSd2rcK3REE+7 vkfnGU0bv/0RA0yV4xV8cDkYDV27tFDH8D2rKz1qwb2ABumAaklgRNCDp/2jcMxhWyVO 979F3I22PVjGxJaBizVGlpXueCS9y+CZVaeM4wSkbZuryO4QMUzvLhvHyraAaG/yKeTs q1/wDRVN2zrDRZqfXJhG4zh1FSMIlk0LTFp+RHH9BHhbhAXLKv1ecHbkqFVUCrdIKaoh IfRDP6mW9ANals3Bvfcu1quWKF49myi7JiQ3D5+opwO5Oc/UW1HmSgKwWYUWG2xEuUao ouXA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ry1lUwCqAfBgfWSwubKT+DxUza2U0Nz1qiU4D2SgsSU=; b=b3ZC3vSa9tKC7TkLnLfgCRVDH+A7ESGvhSANvOwecuTRvoEoPbbCLipwyX5cDQNNL7 PGdVBHwcQIvxDs56M2cIhzKKAcy61GocGq7OhbKhYVKs3mMQzwXWkvED3vIDFdHMvVPU 4F5BF6PdCQtA4w1tKKuElSqr8nt6glTHK4a5gmEQfseY80tDXqT4Hy3q0MKF+MJL+wfB lYtw01enu7fDFrhCO2dvt1DapM7InkESWRKTdmxoCKPVg3JeQIcWiJVwK+SWfJ0QjFYb X6A2FOcPqP012AI9X5TybT8ji2qT3bInmWhQ4ndQVySFYbQiGJh1GKwT9a7fb1hZTF+h rTZQ==
X-Gm-Message-State: APjAAAVgfMDKTidQu4pj+fGSaCdcH2Ba2JtRKIzjpT1rXDHfXvLDuibq k8E7yz3hRhSGo1pohLPgXqUnGpuewytb3g==
X-Google-Smtp-Source: APXvYqz0dFwpVayQhdUQlNjVTnqsraAt8dPLpzg84Bkp+tPYESgNBtP7hOUEeWly23hCz6W2LDx/qw==
X-Received: by 2002:a37:b5c2:: with SMTP id e185mr12255547qkf.247.1570220061949; Fri, 04 Oct 2019 13:14:21 -0700 (PDT)
Received: from [206.123.31.196] ([24.225.159.41]) by smtp.gmail.com with ESMTPSA id 200sm3762349qkf.65.2019.10.04.13.14.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 04 Oct 2019 13:14:21 -0700 (PDT)
From: Marc Blanchet <marc.blanchet@viagenie.ca>
To: "Burleigh, Scott C" <scott.c.burleigh@jpl.nasa.gov>
Cc: DTN WG <dtn@ietf.org>
Date: Fri, 04 Oct 2019 16:14:19 -0400
X-Mailer: MailMate (1.12.5r5635)
Message-ID: <403D9F12-1A6A-406C-8DA6-6E5D147246D9@viagenie.ca>
In-Reply-To: <c337e489e31c43669b0bd2ff8e420698@jpl.nasa.gov>
References: <c337e489e31c43669b0bd2ff8e420698@jpl.nasa.gov>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"; format="flowed"
Content-Transfer-Encoding: 8bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/dtn/28T-FV6uzJPOeszdrWOzxyM4nkw>
Subject: Re: [dtn] CRC discussion
X-BeenThere: dtn@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Delay Tolerant Networking \(DTN\) discussion list at the IETF." <dtn.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dtn>, <mailto:dtn-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dtn/>
List-Post: <mailto:dtn@ietf.org>
List-Help: <mailto:dtn-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dtn>, <mailto:dtn-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 04 Oct 2019 20:14:25 -0000

Scott, seeing no comments on the list, so let’s proceed then.

Marc.

On 18 Sep 2019, at 17:06, Burleigh, Scott C (US 312B) wrote:

> Hi.  During today's Interim meeting of the DTN WG we spent some time 
> discussing the need for CRCs covering the primary blocks of bundles.  
> My understanding of the position we reached in the meeting is as 
> follows:
>
> 1.  The source of a bundle MUST include a CRC in the bundle's primary 
> block unless the bundle includes a Block Integrity Block whose target 
> is the primary block, in which case it still MAY include a CRC in the 
> bundle's primary block.
>
> 2.  CRCs MAY be included in all other blocks, i.e., the payload block 
> and all extension blocks.
>
> 3.  A node that receives a bundle SHOULD validate all CRCs that are 
> present in all blocks of the bundle.
>
> Scott