Internet Engineering Task Force (IETF) B. Leiba
Request for Comments: 8067 Huawei Technologies
BCP: 97 January 2017
Category: Best Current Practice
Updating When Standards Track Documents May Refer Normatively to
Documents at a Lower Level
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
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Leiba Best Current Practice [Page 1]
RFC 8067 Document Downref Update January 2017
Table of Contents
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
[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.
Leiba Best Current Practice [Page 2]
RFC 8067 Document Downref Update January 2017
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
Phone: +1 646 827 0648
Leiba Best Current Practice [Page 3]