[Cbor] Invalid tag (issue 176); notable tags draft

Carsten Bormann <cabo@tzi.org> Tue, 12 May 2020 20:28 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Subject: [Cbor] Invalid tag (issue 176); notable tags draft
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As we discussed in conjunction with https://github.com/cbor-wg/CBORbis/issues/176, we need a registration for an invalid tag, which is reserved so it can be used in an implementation to store the absence of a tag into an integer that would otherwise carry the number of that tag.

I have put the text for a specification for that registration in:

https://www.ietf.org/id/draft-bormann-cbor-notable-tags-00.html#name-iana-considerations

I have also applied for the tag number at IANA.

I took the occasion to start drafting the “notable tags” draft I have been bandying about in recent CBOR meetings.  Most of the text that would make that draft useful is not yet written.  I also need to shop around for permissions to copy over original tag definition texts into that draft.  But the structure is already a good straw man for how I think this document should look like.

Grüße, Carsten