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Additional Key words to Indicate Requirement Levels

Document Type Expired Internet-Draft (individual)
Expired & archived
Author Paul E. Hoffman
Last updated 2008-01-15
RFC stream (None)
Intended RFC status (None)
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


Some document authors want to express requirement levels using the traditional definitions of "MUST" and "SHOULD" from RFC 2119, but also want to express that there is an expectation that later versions of the document may change those requirements. For example, they may want to express "this SHOULD be implemented now, but we expect that this will become a MUST requirement in a future update to this standard". This document defines three new keywords, "MUST-", "SHOULD+", and "SHOULD-" to facilitate such definitions.


Paul E. Hoffman

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