FYI: Extending IDNA to other protocols (Nick Teint)

Shawn Steele Shawn.Steele at
Wed Mar 24 16:50:58 CET 2010

I much prefer the EAI method of using UTF-8 instead of the punycode hack.  (  Indeed several vendors already seem to be working on EAI solutions.

For one thing, punycode has proven that it clutters the layers of an application and leads to terrible confusion about when an IDN name moves from Unicode to Punycode, requiring that the application layer have a deep understanding of DNS.  It'd be much better to "fix" the protocols to make them comply with RFC 2279 "Protocols MUST be able to use the UTF-8 charset", rather than provide hacks.


Date: Tue, 23 Mar 2010 21:16:53 +0100
From: Nick Teint <nick.teint at>
Subject: FYI: Extending IDNA to other protocols
To: idna-update at
        <7dabd4501003231316p2fd9ad24g385b5479af0a6c6 at>
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Today, I've submitted several Internet-Drafts describing a proposed
framework to use IDNA(bis) for non-domain addresses.

The basic idea is to extract anything from the address that fits the
syntax of a valid domain name "label", i.e. strings that roughly match
the "LDH" syntax for "A-labels" and "U-labels". The extracted strings
are then converted using a conversion very similar to IDNAbis.

The draft for the base is:

Examples for profiles:


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