Movatterモバイル変換

Network Working Group                                         J. KlensinRequest for Comments: 4897BCP: 97                                                       S. HartmanUpdates:3967                                                        MITCategory: Best Current Practice                                June 2007Handling Normative References to Standards-Track DocumentsStatus of This Memo   This document specifies an Internet Best Current Practices for the   Internet Community, and requests discussion and suggestions for   improvements.  Distribution of this memo is unlimited.Copyright Notice   Copyright (C) The IETF Trust (2007).Abstract   The Internet Engineering Task Force (IETF) and Request for Comments   (RFC) Editor have a long-standing rule that a document at a given   maturity level cannot be published until all of the documents that it   references as normative are at that maturity level or higher.  This   rule has sometimes resulted in very long publication delays for   documents and some claims that it was a major obstruction to   advancing documents in maturity level.  The IETF agreed on a way to   bypass this rule withRFC 3967.  This document describes a simpler   procedure for downward references to Standards-Track and Best Current   Practice (BCP) documents, namely "note and move on".  The procedure   inRFC 3967 still applies for downward references to other classes of   documents.  In both cases, annotations should be added to such   References.Klensin & Hartman        Best Current Practice                  [Page 1]

RFC 4897                  Normative References                 June 2007Table of Contents1. Introduction ....................................................22. Terminology .....................................................33. Normative Reference Rule ........................................33.1. Source Documents Not Yet Processed by the IESG .............33.2. Documents Already in the RFC Editor Queue ..................44. Target Documents Not on the Standards Track .....................45. Target Documents that Can Be Referenced This Way ................46. Security Considerations .........................................57. Acknowledgements ................................................58. Normative References ............................................51.  Introduction   The IETF and RFC Editor have a long-standing rule (see, e.g.,RFC2026,Section 4.2.4 [RFC2026] and the extended discussion inRFC 3967   [RFC3967]) that a document at a given maturity level cannot be   published until all of the documents to which it makes a normative   reference are at that maturity level or higher.  This rule has   sometimes resulted in very long publication delays for documents and   some claims that it was a major obstruction to advancing documents in   maturity level.  Recognizing the problems that this rule sometimes   caused,RFC 3967 established an exception procedure for normative   downward references under some specific circumstances.  Perhaps   because of its fairly stringent requirements,RFC 3967 has not proven   adequate either to clear the backlog of documents awaiting upgraded   documents or to prevent additional documents from joining that queue.   This document replaces the long-standing rule for downward references   to Standards-Track documents (including BCPs) that are already   published.  For normative references to Standards-Track and BCP   documents, that rule was to hold the newer, referencing, document   until the referenced ones could be brought to the appropriate   maturity level.  It is now possible, following procedures described   below, to simply note the downward normative reference and move on.   This document also updatesRFC 3967.  When downward references from a   source document are approved under the procedure specified in that   specification, we recommend that the references in the approved   (source) document be annotated in the same way as references approved   under this rule.Klensin & Hartman        Best Current Practice                  [Page 2]

RFC 4897                  Normative References                 June 20072.  Terminology   A reference involves two documents, the one in which the reference is   embedded and the document referenced.  Where needed for clarity,   these documents are referred to as the "source document" and "target   document", respectively.   The term "Standards-Track document", as used in this specification,   is assumed to include BCPs but not Informational or Experimental   documents of any variety or origin.3.  Normative Reference Rule   This document specifies an alternative to holding source documents   until all target documents referenced normatively are upgraded or by   applying the procedure ofRFC 3967.3.1.  Source Documents Not Yet Processed by the IESG   An author or editor who requires a normative downward reference to a   Standards-Track RFC uses the following very simple procedure:   o  The reference text (i.e., in the "Normative References" section of      the source document) is written as usual.   o  A note is included in the reference text that indicates that the      reference is to a target document of a lower maturity level, that      some caution should be used since it may be less stable than the      document from which it is being referenced, and, optionally,      explaining why the downward reference is appropriate.   The Internet Engineering Steering Group (IESG) may, at its   discretion, specify the exact text to be used, establish procedures   regarding the text to use, or give guidance on this text.  When   establishing procedures, the IESG should seek appropriate community   review.   These annotations are part of the source document.  If members of the   community consider either the downward reference or the annotation   text to be inappropriate, those issues can be raised at any time   during the document life cycle, just as with any other text in the   document.  There is no separate review of these references.   With appropriate community review, the IESG may establish procedures   for when normative downward references should delay a document and   when downward references should be noted.  Absent specific guidance,   authors and reviewers should use their best judgment.  It is assumed   that, in a significant majority of cases, noting a downward reference   is preferable to delaying publication.Klensin & Hartman        Best Current Practice                  [Page 3]

RFC 4897                  Normative References                 June 2007   At the option of the author, similar notes may be attached to non-   normative references.3.2.  Documents Already in the RFC Editor Queue   The IESG may, at its discretion, specify a procedure to be applied to   source documents that are already in the RFC Editor queue, awaiting   target referenced documents.  The IESG should encourage authors with   documents in the RFC Editor queue awaiting downward references to   Standards-Track RFCs to evaluate whether this new rule is appropriate   for their documents.  If authors believe that adding an annotation   and releasing the document is the best way forward, then the IESG   should ensure that appropriate review is conducted and, if that   review agrees with that of the authors' evaluation, allow the   annotations to be added.  The IESG will announce its decision via the   normal Protocol-Action or Document-Action mechanisms.4.  Target Documents Not on the Standards Track   In the case of a normative reference to a document not on the   standards track that is approved under the procedures defined inRFC3967, the annotation described inSection 3.1 or the retrospective   annotation described inSection 3.2, SHOULD be added to the reference   unless the IESG, after consideration of Last Call input, concludes it   is inappropriate.5.  Target Documents that Can Be Referenced This Way   The "downward reference by annotation" model specified here is   applicable only to published Standards-Track RFCs at lower maturity   levels.   Obviously, such downward references are part of the relevant source   document at IETF Last Call and subject to comments from the   community.   Advancing documents, when appropriate, is still considered preferable   to the use of either this procedure or the one specified inRFC 3967.   This specification does not impose a specific test or requirement to   determine appropriateness.  This is partially because it would be   impossible to do so for the general case, but more so because the   intention is to permit the IESG and the community to balance the   importance of getting a source document published against the time   and difficulty associated with upgrading a target document.  That   requirement is intended to be less stringent than the one ofRFC3967.Klensin & Hartman        Best Current Practice                  [Page 4]

RFC 4897                  Normative References                 June 20076.  Security Considerations   This document specifies an IETF procedure.  It is not believed to   raise any security issues although, in principle, relaxing the   normative downward reference rules for references associated with   security mechanisms could make a specification less stable and hence   less secure.7.  Acknowledgements   This proposal was suggested by a comment by Spencer Dawkins and many   complaints about the negative impact of the current rules.  The   author is unsure about the validity of some of those complaints; the   proposal is, in part, a way to test the validity question.  Spencer   also provided helpful comments on a preliminary version.  It was   revised in response to extensive discussion in the IESG and benefited   significantly by comments from Brian Carpenter.8.  Normative References   [RFC2026]  Bradner, S., "The Internet Standards Process -- Revision              3",BCP 9,RFC 2026, October 1996.   [RFC3967]  Bush, R. and T. Narten, "Clarifying when Standards Track              Documents may Refer Normatively to Documents at a Lower              Level",BCP 97,RFC 3967, December 2004.Authors' Addresses   John C Klensin   1770 Massachusetts Ave, #322   Cambridge, MA  02140   USA   Phone: +1 617 491 5735   EMail: john-ietf@jck.com   Sam Hartman   Massachusetts Institute of Technology   77 Massachusetts Ave   Cambridge, MA  02139   USA   EMail: hartmans-ietf@mit.eduKlensin & Hartman        Best Current Practice                  [Page 5]

RFC 4897                  Normative References                 June 2007Full Copyright Statement   Copyright (C) The IETF Trust (2007).   This document is subject to the rights, licenses and restrictions   contained inBCP 78, and except as set forth therein, the authors   retain all their rights.   This document and the information contained herein are provided on an   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND   THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS   OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Intellectual Property   The IETF takes no position regarding the validity or scope of any   Intellectual Property Rights or other rights that might be claimed to   pertain to the implementation or use of the technology described in   this document or the extent to which any license under such rights   might or might not be available; nor does it represent that it has   made any independent effort to identify any such rights.  Information   on the procedures with respect to rights in RFC documents can be   found inBCP 78 andBCP 79.   Copies of IPR disclosures made to the IETF Secretariat and any   assurances of licenses to be made available, or the result of an   attempt made to obtain a general license or permission for the use of   such proprietary rights by implementers or users of this   specification can be obtained from the IETF on-line IPR repository athttp://www.ietf.org/ipr.   The IETF invites any interested party to bring to its attention any   copyrights, patents or patent applications, or other proprietary   rights that may cover technology that may be required to implement   this standard.  Please address the information to the IETF at   ietf-ipr@ietf.org.Acknowledgement   Funding for the RFC Editor function is currently provided by the   Internet Society.Klensin & Hartman        Best Current Practice                  [Page 6]