Deprecating the "X-" Prefix and Similar Constructs in Application Protocols
RFC 6648, “Deprecating the "X-" Prefix and Similar Constructs in Application Protocols”, is a Best Current Practice document published in June 2012 by P. Saint-Andre, D. Crocker, M. Nottingham. The canonical text is published by the RFC Editor.
Abstract
Historically, designers and implementers of application protocols have often distinguished between standardized and unstandardized parameters by prefixing the names of unstandardized parameters with the string "X-" or similar constructs. In practice, that convention causes more problems than it solves. Therefore, this document deprecates the convention for newly defined parameters with textual (as opposed to numerical) names in application protocols. This memo documents an Internet Best Current Practice.
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 6648 is hosted at rfc-editor.org. Available in TXT,HTML.
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