Re: [Cbor] [COSE] CBOR magic number, file format and tags

Michael Richardson <mcr+ietf@sandelman.ca> Sat, 23 January 2021 21:39 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Carsten Bormann <cabo@tzi.org>
cc: "Dale R. Worley" <worley@ariadne.com>, cbor@ietf.org, doug@ewellic.org
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Date: Sat, 23 Jan 2021 16:39:24 -0500
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Subject: Re: [Cbor] [COSE] CBOR magic number, file format and tags
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Carsten Bormann <cabo@tzi.org> wrote:
    >> 2) Two-element array.

    > Which is mostly a weird way to express a tag, without the need to
    > register it.  Why would this be better than a tag?  (Unless you believe
    > registering them is too onerous or creates too much noise in the
    > registry.)  So I’d prefer using tags, which otherwise have exactly the
    > same properties.  The 1+2+1+4 proposal looks pretty good to me.

It just avoids the CBOR Sequence.
The first element is something.  It can be a CBOR Tag<CBOR>.
The real item is second element.

--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide