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

Michael Richardson <mcr@sandelman.ca> Sat, 23 January 2021 22:46 UTC

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From: Michael Richardson <mcr@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 17:45:56 -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:
    >> It just avoids the CBOR Sequence.  The first element is something.  It
    >> can be a CBOR Tag<CBOR>.  The real item is second element.

    > I’m still intrigued.  So why not just put the tag on the data item to
    > be tagged?

For content that the application doesn't really know a lot about,
(a CBOR compressed certificate for instance), then the second element is
always the thing transmitted.  (With whatever tags are there!)

The application doesn't have to have such intimate knowledge about whether or
not to send the tags.

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