[Cbor] RFC7049bis processing of unknown tags

Michael Richardson <mcr+ietf@sandelman.ca> Wed, 06 May 2020 15:32 UTC

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Date: Wed, 06 May 2020 11:32:39 -0400
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Subject: [Cbor] RFC7049bis processing of unknown tags
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After discussion about #176/#181 I submitted #182:

https://github.com/cbor-wg/CBORbis/issues/182

RFC7049 specified that CBOR tags which were not recognized should be ignored.

RFC7049bis wishes to change this behaviour such that unknown tags would not
be ignored, but would at least, be presented to the application for further
determination. This is a change that would render existing CBOR parsers
instantly invalid.

---

The suggestion is that parsers should be in RFC7049 mode by default, and
applications that want RFC7049bis behaviour should initialize the parser with
an option that enables it [or use a new parser with awareness].

Applications that want to make use of tags defined in RFC7049bis need to put
the parser in RFC7049bis mode.

---

I think that Carsten does not agree with my suggested solution, but I'm not
attached to it.



--
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-