[Cbor] Review of draft-ietf-cbor-packed-02

Russ Housley <housley@vigilsec.com> Mon, 15 March 2021 16:47 UTC

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From: Russ Housley <housley@vigilsec.com>
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Date: Mon, 15 Mar 2021 12:47:48 -0400
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Subject: [Cbor] Review of draft-ietf-cbor-packed-02
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I agreed to review this document during the session at IETF 110.


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Document: draft-ietf-cbor-packed-02
Reviewer: Russ Housley
Review Date: 2021-03-15

Major Concern:

RFC 7049 says that CBOR was designed so that "encoded data should be
self-describing so that a generic decoder can be written."  I di not
expect Packed CBOR to deviate from this design goal.  However, the
feature that allows an application environment, such as a media type,
to define tables does exactly that.  Decode will fail if these table
values are not known to the decoder.

Minor Concern:

In Section 2.1, the text says: "In the abstract, ...".  I am unsure what
this is trying to tell the implementer.  I think it means: "regardless
of the data structure used by an implementer".  I think these words can
be removed.


Section 2: Begins with: "Packed CBOR is defined in two parts:
Referencing packing tables (this section) and setting up packing
tables (Section 3)."  I suggest this text be place at the send of
the Introduction.