Re: [dtn] CRC discussion

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

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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
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Subject: Re: [dtn] CRC discussion
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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