Moving Towards Internationalized Domain Names

Paul Hoffman

Internet Mail Consortium

September 7, 2000

What is covered today

Quick DNS overview Update on the IDN Working Group IDN proposals Transition strategies Next steps (See conference notes for more details)

DNS overview

Today’s host names are a-z, 1-9, and ‘-’ only, and case is ignored in comparisons

Some other ASCII characters have been further restricted (mostly those used in URLs)

There is a strong desire to allow all common naming characters from all scripts in host names

Problems with going to IDN

Although the DNS specification does not restrict host names to ASCII, many implementations do, and that will cause problems if there is a shift to UTF-8 in the protocol

Some protocols that use the DNS (mail and digital certificates, for example), cannot use 8-bit names

IDN Working Group status

New WG web site: <http://www.i-d-n.net> Many proposals before the WG

messages within the DNS, and queries/responses applications DNS

canonicalization and limitations on characters in internationalized names

No consensus yet, and lots of discussions still active

Proposals under active discussion

Main protocols in discussion appear to be IDNE (uses EDNS0 to mark binary requests in the DNS) and IDNRA (involves no changes to the DNS)

“nameprep” is the main proposal for limitations and processing

Transition strategies

Will the changes work if only some of the parts of the DNS are updated?

Must prevent any damage to the the current DNS, and also must look sensible to novice Internet users

This could be biggest stumbling block for any proposal

Next steps for the IDN WG

The working group must focus on a single on-the-wire protocol

That protocol must be bashed heavily by critics and supporters to be sure that it will really do what it is supposed to

Also must start defining what types of characters are wanted and not wanted in host names