Internationalizing Domain Names in Applications
RFC 3490, “Internationalizing Domain Names in Applications”, is a Proposed Standard document published in March 2003 by P. Faltstrom, P. Hoffman, A. Costello. It has been obsoleted by RFC 5890, RFC 5891 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.
Abstract
Until now, there has been no standard method for domain names to use characters outside the ASCII repertoire. This document defines internationalized domain names (IDNs) and a mechanism called Internationalizing Domain Names in Applications (IDNA) for handling them in a standard fashion. IDNs use characters drawn from a large repertoire (Unicode), but IDNA allows the non-ASCII characters to be represented using only the ASCII characters already allowed in so-called host names today. This backward-compatible representation is required in existing protocols like DNS, so that IDNs can be introduced with no changes to the existing infrastructure. IDNA is only meant for processing domain names, not free text. [STANDARDS-TRACK]
What “Proposed Standard” means
An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.
The canonical text of RFC 3490 is hosted at rfc-editor.org. Available in TXT,HTML.
- RFC 3489 STUN - Simple Traversal of User Datagram Protocol Through Network Address Translators
- RFC 3491 Nameprep: A Stringprep Profile for Internationalized Domain Names
- RFC 3488 Cisco Systems Router-port Group Management Protocol
- RFC 3492 Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications
- RFC 3487 Requirements for Resource Priority Mechanisms for the Session Initiation Protocol
- RFC 3493 Basic Socket Interface Extensions for IPv6
- RFC 3486 Compressing the Session Initiation Protocol
- RFC 3494 Lightweight Directory Access Protocol version 2 to Historic Status