[Cbor] Maps: Need for additional compactness?

Christian Amsüss <christian@amsuess.com> Wed, 09 June 2021 16:02 UTC

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Date: Wed, 9 Jun 2021 18:02:45 +0200
From: Christian =?iso-8859-1?Q?Ams=FCss?= <christian@amsuess.com>
To: Emile Cormier <emile.cormier.jr@gmail.com>, Kio Smallwood <kio@mothers-arms.co.uk>, cbor@ietf.org
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Subject: [Cbor] Maps: Need for additional compactness?
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Hello Emile, hello Kio,
and hello CBOR group in general,

during the last CBOR interim meeting[1], the question as to how far we'd
like to go in map-like data structure optimization came up. These do not
relate to the information model (these variations are covered in tags),
but only to how data is put on the wire, so it'd be about variations of
not placing items into inner lists when avoidable, delta encoding for
ordered lists or other compression steps.

An idea floated during the meeting was go with the obvious encoding now,
and only go there later if use cases really need those.

What are your needs with respect to compactness? Does it suffice to
address the high-level (homogenity) aspects of map data structures?


  minutes: https://datatracker.ietf.org/meeting/interim-2021-cbor-10/materials/minutes-interim-2021-cbor-10-202106021600-00
  relevant slides: https://datatracker.ietf.org/meeting/interim-2021-cbor-10/materials/slides-interim-2021-cbor-10-sessa-map-like-data-draft-bormann-cbor-cddl-map-like-data-00
  video: https://www.youtube.com/watch?v=IfrxbspRcQo
  ... and also from me: sorry for the time mismatch.

There's always a bigger fish.
  -- Qui-Gon Jinn