Subject: [Idr] Benjamin Kaduk's Discuss on draft-ietf-idr-capabilities-registry-change-08: (with DISCUSS)

From: Benjamin Kaduk via Datatracker <[email-masked]>
Date: Mon, 04 May 2020 15:32:14 -0700

Benjamin Kaduk has entered the following ballot position for
draft-ietf-idr-capabilities-registry-change-08: Discuss

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DISCUSS:
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(Quite possibly a "discuss discuss"...)
What would the behavior be if someone was shipping an implementation that used
a point in the 128-255 range intending for the "private use" semantics, a
conflicting codepoint was assigned via FCFS, and then needed to use the feature
with conflicting codepoint in that implementation? It seems likely that we
should discuss the plausibility of such scenarios and what options are
available to handle it.

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From: John Scudder <[email-masked]>
Date: Mon, 4 May 2020 22:42:23 +0000

The described scenario (if I understand it correctly) is essentially why we wrote the draft — there isn’t a sane use for “private use” in the context of Capabilities. The reason we worked hard on the implementation survey was to try to catch any gotchas. Of course there can’t be any guarantee of that we didn’t miss something, but any such collision is no different from any other code point collision, whether due to squatting or whatever.

—John

> On May 4, 2020, at 6:32 PM, Benjamin Kaduk via Datatracker <[email-masked]> wrote:
> 
> 
> Please refer to https://urldefense.com/v3/__https://www.ietf.org/iesg/statement/discuss-criteria.html__;!!NEt6yMaO-gk!XlwTiOBYEoZ6FbmvITpDe6sQgYHGqOjOvpudaP4aGJTA6cDhw0V0JhRN-wx_9g$
> https://urldefense.com/v3/__https://datatracker.ietf.org/doc/draft-ietf-idr-capabilities-registry-change/__;!!NEt6yMaO-gk!XlwTiOBYEoZ6FbmvITpDe6sQgYHGqOjOvpudaP4aGJTA6cDhw0V0JhSclIaoGg$
> 
> 
>

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From: Benjamin Kaduk <[email-masked]>
Date: Wed, 6 May 2020 16:43:43 -0700

Hi John,

Sorry for the slow response -- I was away from my inbox for a while and
seem to have missed this message when skimming over for important things to
respond to.

I think you have the right understanding, and as others have noted, having
the document state that a survey was done, and that all known codepoints in
use are being registered, is worth doing.  I also think that we should give
a description of what could go wrong if our survey had missed something, to
make it clear that we understand the scope of what we're doing and still
believe that the cost/benefit tradeoff is in favor of what we're doing.
Given that an existing private use is almost surely within some limited
private scope, it seems like dealing with a potential future conflict
should be a manageable prospect, so I'm not very concerned, but I think
it's important to record our current understanding.

Thanks,

Ben