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Re: [Suit] Packed CBOR

Carsten Bormann <cabo@tzi.org> Thu, 30 July 2020 22:03 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Suit] Packed CBOR
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> 
> 2.  I cannot answer about all CBOR implementations, but I would expect that the ones that I regularly work with are very likely to adopt it.  

Some implementations would only provide the unpacker, some would provide (various complexity levels of) packing as well.  Note that a CBOR library that does not implement any of this still enables doing the pointer-chasing in the application, so the actual coverage may be greater.

> There are some ideas around things like dictionaries which have not been thought through with any degree of completeness.   My personal expectation is that 18 months would be an earliest possible date but others may disagree with that.

The design space is huge, which tends to slow down development.  I think we will design this in a way that the basic tag 6 packing can be combined with other tags to achieve the more esoteric feature sets.  If we manage to get the interface to these (future) tags right, we might not need those 18 months.  (Anything below 12 months to RFC is certainly unlikely.)

Grüße, Carsten

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