[COSE] How COSE items are identified
"Jim Schaad" <ietf@augustcellars.com> Mon, 16 November 2015 07:15 UTC
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From: Jim Schaad <ietf@augustcellars.com>
To: Ace@ietf.org
Date: Sun, 15 Nov 2015 23:12:30 -0800
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Subject: [COSE] How COSE items are identified
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We seem to have a potential problem for how COSE items are identified. Initially, we used an integer inside of the structure to identify it. That is how the current ACE documents are written. This uses a single byte. At the request of Carsten, we moved from doing this to using a tag at the front of the structure. Carsten believes that this can be done with a tag that is in the two byte range when encoded (tag, length=1, tag value). Part of the reason that I agreed was that this was not really being used at the time by the ACE documents. If one is almost always doing encrypted, then one could encode that structure w/o the tag and do the other three structures with the tag. This would probably be ok as it would mostly use the smallest tagging (none) when needed the most and use larger tagging (2 bytes) for the rest of the structures. Alternatively, we could modify the document to request the assignment of tags in the one byte range for the most common structures and two bytes for the less common structures (and have arguments about which is which). Alternatively, we could revert back to putting an integer tag inside of the array structure. Comments on this are requested. Jim
- [COSE] How COSE items are identified Jim Schaad
- Re: [COSE] How COSE items are identified Justin Richer