Re: pseudo-TLDs

[Frank Ellermann <nobody@xxxxxxxxxxxxxxxxx>]

Forrest J. Cavalier III wrote:

> I think prefix dot is much better than underscore.

Underscore is a "traditional" way to do "funny" things
with DNS labels.  Or at least it pops up in discussions
I've seen again and again (MARID, DKIM, etc.)

For labels a dot would be the worst idea after 0xFF ;-)

Okay, here we're not really creating DNS labels, we
only try to avoid potential conflicts with FQDNs.

As far as host names are concerned undersore is good
enough - and for your dot idea there's also a (small)
chance to get it wrong if say host seen.site.example
exists with ...!.SEEN.site.example!... in the Path.

> Why use up that option and force future innovators
> into a corner for no good reason?

It's what everybody else does or proposes... <shrug />
Some problems with both "leading keyword" proposals:

- Russ or Richard said that diag-keywords like SEEN
  or MISMATCH are not really useful.

- So if we introduce it anyway let's at least stick
  to "common practice" for .MISMATCH (= pseudo-TLD)

- If we do this for .MISMATCH then using a different
  approach for "SEEN" would be odd (assuming that we
  introduce "SEEN" at all)

- Apparently it's *_not impossible_* to reserve such
  pseudo-TLDs, and I didn't know that RfC 2860 detail:
  <http://mid.gmane.org/4333DDFF.8020909@xxxxxxxxxxxxxx>

- We're still free to do "the right thing" for POSTED,
  and introduce ...!.POSTED!... or ...!_POSTED!... (?)

                     Bye, Frank