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

worley@ariadne.com Sat, 23 January 2021 03:14 UTC

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From: worley@ariadne.com (Dale R. Worley)
To: Michael Richardson <mcr@sandelman.ca>
Cc: cbor@ietf.org, doug@ewellic.org
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Sender: worley@ariadne.com (Dale R. Worley)
Date: Fri, 22 Jan 2021 22:14:44 -0500
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Subject: Re: [Cbor] [COSE] CBOR magic number, file format and tags
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Here's an alternative.  It is aligned with the magic number tag of CBOR
itself (55799) and the CBOR way of doing things.  Specifically, reserve
a large range of tags (such as 55800 to 65000, or 100000 to 109999) for
use as magic numbers; the CBOR object has the appropriate magic number
tag applied to that, and optionally, the CBOR magic number tag 55799
applied to that.  That can leave the generic CBOR magic number visible
at the start of the file, immediately followed by the bytes of the
specific magic number for the object type.

Dale