Re: [kitten] Service discovery URI field case-sensitivity

Greg Hudson <ghudson@mit.edu> Thu, 13 October 2016 15:29 UTC

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To: Matt Rogers <mrogers@redhat.com>, kitten@ietf.org
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From: Greg Hudson <ghudson@mit.edu>
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Date: Thu, 13 Oct 2016 11:28:58 -0400
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Subject: Re: [kitten] Service discovery URI field case-sensitivity
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On 10/12/2016 04:46 PM, Matt Rogers wrote:
> The service discovery draft needs some clarification of the encoding
> and case sensitivity for the URI field values, and I have heard some
> different views on how they should be defined.

This is in reference to draft-mccallum-kitten-krb-service-discovery-03.

> First I believe the scheme should be case-insensitive per BCP 35 advice
> on URI scheme values. 

Our scheme, "krb5srv"?  Formally, I'm not sure if we have to specify
that when defining a new scheme, but informally we should recommend that
URI record processing code match the scheme case-insensitively.

The scheme in the transport-info for kkdcp should also be matched
case-insensitively, of course.

> Overall my preference would be to define in their respective sections,
> the scheme, flags, and transport-type fields as case-insensitive and
> say the transport-info field's case rules are to determined by the
> transport specification.  Although this limits the flags, If we really
> ran out of flags in the future then the document could be updated.

Agreed.  It's unlikely that we will ever add a second flag; it's
vanishingly unlikely that we will need more than 26 (or 36 with digits,
or whatever).