Internet Engineering Task Force (IETF)                          B. Leiba
Request for Comments: 8067                           Huawei Technologies
BCP: 97                                                     January 2017
Updates: 3967
Category: Best Current Practice
ISSN: 2070-1721

Updating When Standards Track Documents May Refer Normatively to
Documents at a Lower Level

Abstract

   RFC 3967 specifies a process for allowing normative references to
   documents at lower maturity levels ("downrefs"), which involves
   calling out the downref explicitly in the Last Call notice.  That
   requirement has proven to be unnecessarily strict, and this document
   updates RFC 3967, allowing the IESG more flexibility in accepting
   downrefs in Standards Track documents.

Status of This Memo

   This memo documents an Internet Best Current Practice.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It has been approved for publication by the Internet
   Engineering Steering Group (IESG).  Further information on BCPs is
   available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc8067.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  The IESG's Responsibility with Respect to Downrefs  . . . . .   2
   3.  Security Considerations . . . . . . . . . . . . . . . . . . .   3
   4.  Normative References  . . . . . . . . . . . . . . . . . . . .   3
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   3

1. Introduction

   [RFC3967] notes the importance of assuring that normative references
   from Standards Track and Best Current Practice (BCP) documents are
   appropriately mature, and specifies a process for allowing normative
   references to documents at lower maturity levels ("downrefs").  That
   process starts at IETF Last Call (see Section 3 of [RFC3967]):

      For Standards Track or BCP documents requiring normative reference
      to documents of lower maturity, the normal IETF Last Call
      procedure will be issued, with the need for the downward reference
      explicitly documented in the Last Call itself.  Any community
      comments on the appropriateness of downward references will be
      considered by the IESG as part of its deliberations.

   Section 2 of [RFC3967] lists some conditions under which downrefs may
   make sense.  In addition to those, it has become common for working
   groups to produce foundational documents (which contain important
   information such as terminology definitions and architectural design
   and considerations) at Informational status, and those documents are
   often needed as normative references in the Standards Track protocol
   documents that follow.

   The requirement to explicitly mention the downrefs and the need for
   them in the Last Call message has proven to be unnecessarily
   restrictive and has often resulted in unnecessary repetitions of Last
   Call, with the corresponding delay and with no real benefit.

2. The IESG's Responsibility with Respect to Downrefs

   The process in RFC 3967 is hereby updated to specify that explicitly
   documenting the downward references in the Last Call message is
   strongly recommended but not required.  The responsible AD should
   still check for downrefs before sending out the Last Call notice, but
   if an undetected downref is noticed during Last Call or IESG review,
   any need to repeat the Last Call is at the discretion of the IESG.
   However, the process in RFC 3967 is not fundamentally altered: If the
   IESG decides not to repeat the Last Call, the status of the affected
   downrefs is not changed, and the process in RFC 3967 will still apply
   if those downrefs are used in the future.

   This gives the IESG the responsibility to determine the actual
   maturity level of the downward reference with respect to the document
   at hand, and to decide whether or not it is necessary to explicitly
   ask the IETF community for comments on the downref on a case-by-case
   basis.  In making that decision, the IESG should take into account
   the general discussion in RFC 3967.  The responsible AD should make
   sure that the omission is recorded as a comment in the datatracker.

3. Security Considerations

   Referencing immature protocols can have security and stability
   implications, and the IESG should take that into account when
   deciding whether re-consulting the community is useful.

4. Normative References

   [RFC3967]  Bush, R. and T. Narten, "Clarifying when Standards Track
              Documents may Refer Normatively to Documents at a Lower
              Level", BCP 97, RFC 3967, DOI 10.17487/RFC3967, December
              2004, <http://www.rfc-editor.org/info/rfc3967>.

Author's Address

   Barry Leiba
   Huawei Technologies

   Phone: +1 646 827 0648
   Email: barryleiba@computer.org
   URI:   http://internetmessagingtechnology.org/