Re: [idn] Domain names and ASCII compatibility

[Mark.Andrews@nominum.com]

Paul,
      the point trying to be made is that domain names are more that
host names *and* that encoding rules for idn that restrict idn to host
name syntax (no periods in labels, etc.) will break existing
functionality.  In otherwords we need to internationalise uses of *all*
domain names not just those which are host names.

> 
> >A domain name can be used for many things, two you often have met
> >is host name and e-mail address. Examples are:
> >   Host name: orion.world.net
> >   E-mail:    kent\.xson.mail.net (same as kent.xson@mail.net).
> >Note that the e-mail address can contain a dot (.).
> 

To put the above into context see the following SOA record.

example.com. 3600 IN SOA orion.world.net. kent\.xson.mail.net. 1 20 10 3600 0

If I want to let example.com know that there is a problem I would send
email to kent.xson@mail.net.  Or for another example look up the SOA
for andrews.wattle.id.au.
	
> Sorry, but the email part of this is incorrect. RFC 1034 uses this as a=20
> hack to fit email addresses into zone files, where "@" is a special=20
> character, at least in BIND. You can see from RFC 821 that=20
> "kent\.xson.mail.net" will not work either as a source address or as a=20
> delivery address.

	He wasn't saying you could use it without reversing the
	translation.
> 
> >We are defining internationalisation of domain names, not just
> >host names. So it should be possible to have names like:
> >    Host name: www.g=E5s.net
> >    E-mail:    k=E5re.=E5kesson@g=E5s.net
> 
> Again, the email part of this is also incorrect. RFC 822 very clearly=20
> states that the addresses cannot have characters outside 0-127 (with some=20
> restrictions in this range).

	Yes and RFC 952 clearly states that hostnames are "A" - "Z",
	"0" - "9", "-" and ".".  What is your point? The examples were
	clearly prefixed with the comment that this is where we should be
	heading.

> 
> We should all be more careful not to misstate the current capabilities of=20
> IETF protocols.

	He didn't.
> 
> Please also note that this thread tends to indicate that that email is the=
> =20
> only protocol which cannot use UTF-8. That's far from true. The limitations=
> =20
> of PKIX and SNMP have also been discussed on this mailing list. Saying=20
> "we'll do whatever we want and all the existing protocols that our choice=20
> breaks will just have to fix themselves and then get the fixes deployed"=20
> doesn't really acknowledge that mail, security, and network management are=
> =20
> considered as much a part of the foundation of the Internet as DNS is.
> 
> --Paul Hoffman, Director
> --Internet Mail Consortium
> 
> 
	Mark
--
Mark Andrews, Nominum Inc. / Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark.Andrews@nominum.com