Matching of Language Tags
RFC 4647, “Matching of Language Tags”, is a Best Current Practice document published in September 2006 by A. Phillips, M. Davis. It obsoletes RFC 3066. The canonical text is published by the RFC Editor.
Abstract
This document describes a syntax, called a "language-range", for specifying items in a user's list of language preferences. It also describes different mechanisms for comparing and matching these to language tags. Two kinds of matching mechanisms, filtering and lookup, are defined. Filtering produces a (potentially empty) set of language tags, whereas lookup produces a single language tag. Possible applications include language negotiation or content selection. This document, in combination with RFC 4646, replaces RFC 3066, which replaced RFC 1766. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.
What “Best Current Practice” means
Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.
The canonical text of RFC 4647 is hosted at rfc-editor.org. Available in TXT,HTML.
- RFC 4646 Tags for Identifying Languages
- RFC 4648 The Base16, Base32, and Base64 Data Encodings
- RFC 4645 Initial Language Subtag Registry
- RFC 4649 Dynamic Host Configuration Protocol for IPv6 Relay Agent Remote-ID Option
- RFC 4644 Network News Transfer Protocol Extension for Streaming Feeds
- RFC 4650 HMAC-Authenticated Diffie-Hellman for Multimedia Internet KEYing
- RFC 4643 Network News Transfer Protocol Extension for Authentication
- RFC 4642 Using Transport Layer Security with Network News Transfer Protocol