RFC 3492

"Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications (IDNA)", March 2003

Canonical URL:

http://www.rfc-editor.org/rfc/rfc3492.txt
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Status:

PROPOSED STANDARD

Updated by:

RFC 5891

Author:

A. Costello

Stream:

IETF

Source:

idn (int)

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Abstract

Punycode is a simple and efficient transfer encoding syntax designed for use with Internationalized Domain Names in Applications (IDNA). It uniquely and reversibly transforms a Unicode string into an ASCII string. ASCII characters in the Unicode string are represented literally, and non-ASCII characters are represented by ASCII characters that are allowed in host name labels (letters, digits, and hyphens). This document defines a general algorithm called Bootstring that allows a string of basic code points to uniquely represent any string of code points drawn from a larger set. Punycode is an instance of Bootstring that uses particular parameter values specified by this document, appropriate for IDNA. [STANDARDS-TRACK]

For the definition of Stream, see RFC 4844.