Re: Services and top-level DNS names (was: Re: Update of RFC 2606

John Levine <> Sat, 05 July 2008 13:00 UTC

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Date: Sat, 5 Jul 2008 09:00:36 -0400 (EDT)
From: John Levine <>
To: Mark Andrews <>
Subject: Re: Services and top-level DNS names (was: Re: Update of RFC 2606
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>> As someone else pointed out, there are currently about two dozen TLDs with
>> A or MX records at the apex.  Some of them have been like that for many
>> years, and as best I can tell, the Internet has not thereby collapsed.
> 	How many label our hosts with two letter domain names?

Beats me, but since there are several hundred TLDs, it seems to me that 
the chances are pretty low that everyone in the world has managed to avoid 
using them as host names.

> 	Do you have any evidence that they have not caused problems?

Hey, you're the one claiming that there's a global disaster in progress of 
which nobody seems to be aware.  If there's evidence, tell us about it.

>        I suspect that other sites that used the names just put up
>        with the pain of renamimg hosts along with the resultant
>        risk of email being misdirected.

Perhaps you could start by asking people at how long their mail 
has been unusable.

Look, we all know there's an unlimited number of ways one can screw up 
mail and web configuration.  If you put an underscore in the name of a web 
server, as often as not it sort of works even though it's flatly forbidden 
by RFCs.  Or if you put an @ or % character in the local part of your 
e-mail address, it'll fail all over the place even though the RFCs say 
that's fine.

Why is this particular configuration issue so uniquely awful that the IETF 
and ICANN need to tie themselves up in knots about it?  ICANN has plenty 
of real problems on its plate, like registrars who steal people's names 
and won't give them back.  This isn't one of them.

John Levine,, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be,, ex-Mayor
"More Wiener schnitzel, please", said Tom, revealingly.
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