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

Michael Richardson <mcr+ietf@sandelman.ca> Sat, 23 January 2021 20:01 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Carsten Bormann <cabo@tzi.org>, "Dale R. Worley" <worley@ariadne.com>, cbor@ietf.org, doug@ewellic.org
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Date: Sat, 23 Jan 2021 15:01:22 -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:
    > Right.  Something like this would probably make sense as an alternative
    > to the primary approach proposed, which is based on CBOR sequences.  If
    > you want to keep the magic-numbered file a single data item, this is
    > the way to go.

I am personally agnostic about CBOR Sequence vs something else.

I believe that:
  a) the magic number needs to be at least 4 bytes
  b) we shouldn't mandate that it be transmitted on the wire.

Being able to split off the magic part easily make sense to me.
That's why I proposed either:
  1) CBOR Sequence
  2) Two-element array.

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

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