Re: An IANA Registry for DNS TXT RDATA (I-D Action: draft-klensin-iana-txt-rr-registry-00.txt)

[John C Klensin <[e-mail]>]

--On Saturday, August 31, 2013 23:50 +0900 Masataka Ohta
<[e-mail]> wrote:

> The draft does not assure that existing usages are compatible
> with each other.

It absolutely does not.  I actually expect it to help identify
some usages that are at least confusing and possible
incompatible.

> Still, the draft may assure new usages compatible with each
> other.

That is the hope.

> However, people who want to have new (sub)types for the new
> usages should better simply request new RRTYPEs.

I agree completely.  But that has nothing to do with this draft:
the registry is simply addressed to uses that overload TXT, not
to arguing why they shouldn't (or why the use of label prefixes
or suffixes is sufficient to make protocol use of TXT reasonable.

> If we need subtypes because 16bit RRTYPE space is not enough
> (I don't think so), the issue should be addressed by itself
> by introducing a new RRTYPE (some considerations on subtype
> dependent caching may be helpful), not TXT, which can assure
> compatibilities between subtypes.

Again, I completely agree.  But it isn't an issue for this
proposed registry.

> For the existing usages, some informational RFC, describing
> compatibilities (or lack of them) between the existing usages,
> might help.

Yes, I think so.

thanks,
   john