[dtn] CRC discussion

"Burleigh, Scott C (US 312B)" <scott.c.burleigh@jpl.nasa.gov> Wed, 18 September 2019 21:06 UTC

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From: "Burleigh, Scott C (US 312B)" <scott.c.burleigh@jpl.nasa.gov>
To: DTN WG <dtn@ietf.org>
Thread-Topic: CRC discussion
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Date: Wed, 18 Sep 2019 21:06:28 +0000
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Subject: [dtn] CRC discussion
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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.