Subject: [Bundled-domain-names] Bundles in practice

From: "John R Levine" <[email-masked]>
Date: 4 Feb 2016 22:01:49 -0500

I admire the bravery of those of you who jumped into the name bundling swamp.

It might be useful to identify some places where various approaches to 
bundling are in use now, since it could give us some hints about how well 
it works.  Here's some we found in and since RFC 6927.

* DNAME at 2LD

This is used in .CAT and I think .GR.  In .CAT, they bundle accented and 
unaccented letters, so if you register exámple.cat, you also get 
example.cat, and they add a dname:

   exámple.cat. DNAME example.cat.

Having looked at it, I can say this works very badly.  For one thing, 
since DNAME only affects descendant names, www.exámple.cat is defined, but 
plain exámple.cat is not which among other things means that email doesn't 
work.  I spot checked a bunch of .cat web site and found that almost 
without exception, web servers just provision the unaccented name and the 
accented one gives you an error or a default page.

* DNAME at TLD

Taiwan makes the simplified character version of its Chinese name
a DNAME for the traditional version:

xn--kprw13d. 86400	IN	DNAME	xn--kpry57d.

This avoids the missing 2LD problems that .CAT has, but I don't
read Chinese so I don't know how well it works in practice.

* Parallel name servers

PIR's new .NGO and .ONG domains are always paired, so if you register a 
name in one, you get the same name in the other pointing at the same name 
servers.  I've registered a name in .NGO and so far the most notable thing 
I've discovered is that getting DNSSEC DS records provisioned is really 
painful. Your record at your registrar just shows the version you 
registered, so to do the other one needs some ill-defined kludge. 
(Actually, my registrar can't do DNSSEC at all for .NGO, but I hear the 
kludge is coming.)

Other than that it's straightforward to configure the DNS, but of course 
it's up to me to decide how similar I want the two zones to be.

R's,
John