"X-" Considered Harmful

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Last updated 2014-07-02 (latest revision 2010-10-19)
Replaced by draft-ietf-appsawg-xdash
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Many application protocols use named parameters to represent data (for example, header fields in Internet mail messages and HTTP requests). Historically, protocol designers and implementers have often differentiated between "standard" and "experimental" parameters by prefixing experimental parameters with the string "X-". This document argues that, on balance, the "X-" convention has more costs than benefits.


Peter Saint-Andre (psaintan@cisco.com)

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