RFC 5137 · BEST CURRENT PRACTICE · 2008

ASCII Escaping of Unicode Characters

Overview

RFC 5137, “ASCII Escaping of Unicode Characters”, is a Best Current Practice document published in February 2008 by J. Klensin. The canonical text is published by the RFC Editor.

Abstract

There are a number of circumstances in which an escape mechanism is needed in conjunction with a protocol to encode characters that cannot be represented or transmitted directly. With ASCII coding, the traditional escape has been either the decimal or hexadecimal numeric value of the character, written in a variety of different ways. The move to Unicode, where characters occupy two or more octets and may be coded in several different forms, has further complicated the question of escapes. This document discusses some options now in use and discusses considerations for selecting one for use in new IETF protocols, and protocols that are now being internationalized. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

Abstract as published in the RFC, via rfc-editor.org.

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

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