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Internationalizing Domain Names in Applications (IDNA)

Document Type Expired Internet-Draft (individual in int area)
Expired & archived
Authors Patrik Fältström , Paul E. Hoffman , Adam M. Costello
Last updated 2015-10-14 (Latest revision 2004-04-14)
RFC stream Internet Engineering Task Force (IETF)
Stream WG state (None)
Document shepherd (None)
IESG IESG state Expired (IESG: Dead)
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD Scott Hollenbeck
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


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.


Patrik Fältström
Paul E. Hoffman
Adam M. Costello

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)