Re: [Cbor] Base-8 OIDs (or, where not to optimize)

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 04 September 2020 00:30 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Carsten Bormann <cabo@tzi.org>, cbor@ietf.org
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Date: Thu, 03 Sep 2020 20:30:04 -0400
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Subject: Re: [Cbor] Base-8 OIDs (or, where not to optimize)
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Carsten Bormann <cabo@tzi.org> wrote:
    > If I count right, the popular OID 1.3.6.1.4.1.9.9.109.1.1.1.1.5 has 9
    > places that are now one nibble shorter and one that is 1 nibble longer,
    > so we go from 13 bytes (with special case for first number) to 18
    > nibbles (without special case), i.e., 9 bytes.

Some Cisco 5minute CPU average, from SNMP land, I guess.

    > It took approximately one morning shower (*) to

Such an old-fashioned unit.  The young kids now use "COVID-19 socially-distanced grocery store bank line"

    > $64000 question: Why am I not proposing that we standardize this optimization?

Also quaint units :-)

1) I feel it's only super useful for SNMP-like things.
2) I'm uncertain if it is consistently reversible to DER such that signatures
   will work.
3) I think it might encourage more DER encoding rather than CBOR-encoded-YANG.
4) If we couldn't get base-128 right...

--
Michael Richardson <mcr+IETF@sandelman.ca>   . o O ( IPv6 IøT consulting )
           Sandelman Software Works Inc, Ottawa and Worldwide