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[Cbor] List of all serialization variation (was Re: Working Group Last Call on Serialization draft)

Laurence Lundblade <lgl@island-resort.com> Thu, 03 September 2026 15:57 UTC

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From: Laurence Lundblade <lgl@island-resort.com>
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Date: Thu, 03 Sep 2026 08:57:40 -0700
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To: Joe Hildebrand <hildjj@cursive.net>
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CC: Barry Leiba <barryleiba@gmail.com>, CBOR Working Group <cbor@ietf.org>
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Subject: [Cbor] List of all serialization variation (was Re: Working Group Last Call on Serialization draft)
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Appreciate the thorough review!

> On Aug 18, 2026, at 12:05 PM, Joe Hildebrand <hildjj@cursive.net> wrote:
> 
> s2.1.1: I suggest "it may mandate deterministic serialization for all implementations in order to eliminate all serialization variability" -> "it may mandate deterministic serialization for all implementations in order to minimize serialization variability", since there are other sources of serialization variability.

I can’t think of any other sources of serialization variability. Seems important to be sure we got themm all. They are listed in the description of [General Serialization]. Map sort ordering is missing, but I will add it [PR-unordered]. Am I missing something?

 - map sorting
 - def/indef lengths
 - CBOR argument length
 - float length


There is variability at the data model level that needs to be addressed for full determinism of a protocol, but that is not serialization variation.

LL


[General Serialization]: https://www.ietf.org/archive/id/draft-ietf-cbor-serialization-08.html#name-general-serialization
[PR-unordered: https://github.com/cbor-wg/draft-ietf-cbor-serialization/pull/84/changes

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