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Early IANA Allocation of Standards Track Code Points

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 7120.
Author Michelle Cotton
Last updated 2015-10-14 (Latest revision 2013-10-16)
Replaces draft-rfc4020bis
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status Best Current Practice
Stream WG state (None)
Document shepherd Adrian Farrel
Shepherd write-up Show Last changed 2013-10-17
IESG IESG state Became RFC 7120 (Best Current Practice)
Action Holders
Consensus boilerplate Yes
Telechat date (None)
Responsible AD Adrian Farrel
Send notices to (None)
IANA IANA review state IANA OK - Actions Needed
IANA action state RFC-Ed-Ack
Network Working Group                                          M. Cotton
Internet-Draft                                                     ICANN
Obsoletes: 4020 (if approved)                           October 16, 2013
Intended status: BCP
Expires: April 19, 2014

          Early IANA Allocation of Standards Track Code Points


   This memo describes the process for early allocation of code points
   by IANA from registries for which "Specification Required", "RFC
   Required", "IETF Review", or "Standards Action" policies apply.  This
   process can be used to alleviate the problem where code point
   allocation is needed to facilitate desired or required implementation
   and deployment experience prior to publication of an RFC that would
   normally trigger code point allocation.

   This document obsoletes RFC 4020.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 19, 2014.

Copyright Notice

   Copyright (c) 2013 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
   ( in effect on the date of
   publication of this document.  Please review these documents

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   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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 3
   2.  Conditions for Early Allocation . . . . . . . . . . . . . . . . 4
   3.  Process for Early Allocation  . . . . . . . . . . . . . . . . . 4
     3.1.  Request . . . . . . . . . . . . . . . . . . . . . . . . . . 5
     3.2.  Follow-Up . . . . . . . . . . . . . . . . . . . . . . . . . 5
     3.3.  Expiry  . . . . . . . . . . . . . . . . . . . . . . . . . . 6
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 7
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 8
     6.1.  Normative References  . . . . . . . . . . . . . . . . . . . 8
     6.2.  Informative References  . . . . . . . . . . . . . . . . . . 8
   Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . . . 8
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . . . 8

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1.  Introduction

   In protocol specifications documented in RFCs, there is often a need
   to allocate code points for various objects, messages, or other
   protocol entities so that implementations can interoperate.  Many of
   these code point spaces have registries handled by the Internet
   Assigned Number Authority (IANA).  Several IANA allocation policies
   are described in RFC 5226 [RFC5226].  Some of them, such as "First
   Come First Served" or "Expert Review", do not require a formal IETF
   action before the IANA performs allocation.  However, in situations
   where code points are a scarce resource and/or the IETF community has
   consensus to retain tight control of the registry content, policies
   such as "IETF Review" (formerly "IETF Consensus"), or "Standards
   Action" have been used.  Such allocation policies represents a
   problem in situations where implementation and/or deployment
   experience are desired or required before the document becomes an

   To break the deadlock, document authors often choose some "seemingly
   unused" code points, often by selecting the next available value from
   the registry; these may turn out to be different from those later
   assigned by IANA.  To make this problem worse, "pre-RFC"
   implementations are often developed and deployed based on these code
   point selections.  This creates several potential interoperability
   problems between early implementations and implementations of the
   final standard, as described below:

   1.  IANA allocates code points different from those that early
       implementations assumed would be allocated.  Early
       implementations won't interoperate with standard ones.

   2.  IANA allocates code points for one extension while a "pre-RFC"
       implementation of a different extension chooses the same code
       point.  The different extensions will collide on the same code
       point in the field.

   This gets in the way of the main purpose of standards; namely, to
   facilitate interoperable implementations.

   It is easy to say that pre-RFC implementations should be kept private
   and should not be deployed; however, both the length of the standards
   process and the immense value of early implementations and early
   deployments suggest finding a better solution.  As an example, in the
   case of documents produced by Working Groups in the Routing Area, a
   pre-RFC implementation is highly desirable and sometimes even
   required [RFC4794], and early deployments provide useful feedback on
   the technical and operational quality of the specification.

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   This memo addresses the early allocation of code points so that
   reservations are made in the IANA registries before the publication
   of an RFC.  The early allocation mechanisms are applied only to
   spaces whose allocation policy is "Specification Required" (where an
   RFC is used as the stable reference), "RFC Required", "IETF Review",
   or "Standards Action".  For an explanation of these allocation
   policies, see [RFC5226].

   A policy for IANA early allocations was previously described in
   [RFC4020].  This document obsoletes RFC 4020 and adds other
   registration procedures to the types of registries that can qualify
   for early allocation.

2.  Conditions for Early Allocation

   The following conditions must hold before a request for early
   allocation of code points will be considered by IANA:

   a.  The code points must be from a space designated as "RFC
       Required", "IETF Review", or "Standards Action".  Additionally
       code points from a "Specification Required" are allowed if the
       specification will be published as an RFC.

   b.  The format, semantics, processing, and other rules related to
       handle the protocol entities defined by the code points
       (henceforth called "specifications") must be adequately described
       in an Internet-Draft.

   c.  The specifications of these code points must be stable; i.e., if
       there is a change, implementations based on the earlier and later
       specifications must be seamlessly interoperable.

   d.  The working group chairs and ADs judge that there is sufficient
       interest in the community for early (pre-RFC) implementation and
       deployment, or that failure to make an early allocation might
       lead to contention for the code point in the field.

3.  Process for Early Allocation

   There are three processes associated with early allocation: making
   the request for code points; following up on the request; and
   revoking an early allocation.  It cannot be emphasized enough that
   these processes must have a minimal impact on IANA itself, or they
   will not be feasible.

   The processes described below assume that the document in question is

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   the product of an IETF Working Group.  If this is not the case,
   replace "WG chairs" below with "Shepherding Area Director".

3.1.  Request

   The process for requesting and obtaining early allocation of code
   points is as follows:

   1.  The authors (editors) of the document submit a request for early
       allocation to the Working Group chairs, specifying which code
       points require early allocation and which document they should be
       assigned to.

   2.  The WG chairs determine whether the conditions for early
       allocations described in section 2 are met; particularly,
       conditions (c) and (d).

   3.  The WG chairs gauge whether there is consensus within the WG that
       early allocation is appropriate in the case of the given

   4.  If steps 2) and 3) are satisfied, the WG chairs request approval
       of the Area Director(s).  The Area Director(s) may apply
       judgement to the request especially if there is a risk of
       registry depletion.

   5.  If the Area Directors approve step 4, the WG chairs request IANA
       to make an early allocation.

   6.  IANA makes an allocation from the appropriate registry, marking
       it as "Temporary", valid for a period of one year from the date
       of allocation.  The date of first allocation and the date of
       expiry are also recorded in the registry and made visible to the

   Note that Internet-Drafts should not include a specific value of a
   code point until IANA has completed the early allocation for this

3.2.  Follow-Up

   It is the responsibility of the document authors and the Working
   Group chairs to review changes in the document, and especially in the
   specifications of the code points for which early allocation was
   requested, to ensure that the changes are backward compatible.  If at
   some point changes that are not backward compatible are nonetheless
   required, a decision needs to be made as to whether previously
   allocated code points must be deprecated (see section 3.3 for more

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   information on code point deprecation).  The considerations include
   aspects such as the possibility of existing deployments of the older
   implementations and, hence, the possibility for a collision between
   older and newer implementations in the field.  If the document
   progresses to the point at which IANA normally makes code point
   allocations, it is the responsibility of the authors and the WG
   chairs to remind IANA that there were early allocations, and of the
   code point values so allocated, in the IANA Considerations section of
   the RFC-to-be.  Allocation is then just a matter of removing the
   "Temporary" tag from the allocation description.

3.3.  Expiry

   As described in Section 3.1, each Temporary assignment is recorded in
   the registry with the date of expiry of the assignment.  If an early
   allocation expires before the document progresses to the point where
   IANA normally makes allocations, the authors and WG chairs may repeat
   the process in section 3.1 to request renewal of the code points.  At
   most, one renewal request may be made; thus, authors should choose
   carefully when the original request is to be made.

   As an exception to the above rule, under rare circumstances, more
   than one allocation renewal may be justified.  All such further
   renewal requests must be reviewed by the IESG.  The renewal request
   to the IESG must include the reasons why such further renewal is
   necessary, and the WG's plans regarding the specification.

   If a follow-up request is not made, or the document fails to progress
   to an RFC, the assignment will remain visible in the registry but the
   temporary assignment will be shown to have expired as indicated by
   the expiry date.  The WG chairs are responsible for informing IANA
   that the expired assignments are not required and that the code
   points are to be marked "deprecated".

   A deprecated code point is not marked as allocated for use as
   described in any document (that is, it is not allocated), and is not
   available for allocation in a future document.  The WG chairs may
   inform IANA that a deprecated code point can be completely de-
   allocated (i.e., made available for new allocations) at any time
   after it has been deprecated.  Factors influencing this decision will
   include whether there may be implementations using the previous
   temporary allocation, and the availability of other unallocated code
   points in the registry.

   Implementers and deployers need to be aware that this deprecation and
   de-allocation could take place at any time after expiry, and an
   expired early allocation is therefore best considered as deprecated.

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   It is not IANA's responsibility to track the status of allocations,
   their expiration, or when they may be re-allocated.

   Note that if a document is submitted for review to the IESG and at
   the time of submission some early allocations are valid (not
   expired), these allocations must not be considered to have expired
   while the document is under IESG consideration or waiting in the RFC
   Editor's queue after approval by the IESG.

4.  IANA Considerations

   This document defines procedures for early allocation of code points
   in the registries with the "Specification Required", "RFC Required",
   "IETF Review", and "Standards Action" policies and as such directly
   affects IANA.  This document removes the need for registries to be
   marked as specifically allowing early allocation.  IANA is requested
   to clean up the registries by removing any such markings.

5.  Security Considerations

   It is important to keep in mind 'denial of service' attacks on IANA
   as a result of the processes in this memo.  There are two that are
   immediately obvious: depletion of code space by early allocations and
   process overloading of IANA itself.  The processes described here
   attempt to alleviate both of these, but they should be subject to
   scrutiny by IANA to ensure protection, and IANA may at any time
   request the IESG to suspend the procedures described in this

   There is a significant concern that the procedures in this document
   could be used as an end-run on the IETF process to achieve code point
   allocation when an RFC will not be published.  For example, a WG or a
   WG chair might be put under pressure to obtain an early allocation
   for a protocol extension for a particular company or for another SDO
   even though it might be predicted that an IETF LC or IESG Evaluation
   would reject the approach that is documented.  The requirement for AD
   consent of early review is an important safe-guard, and ADs with any
   concern are strongly recommended to escalate the issue for IESG-wide

6.  References

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6.1.  Normative References

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

6.2.  Informative References

   [RFC4020]  Kompella, K. and A. Zinin, "Early IANA Allocation of
              Standards Track Code Points", BCP 100, RFC 4020,
              February 2005.

   [RFC4794]  Fenner, B., "RFC 1264 Is Obsolete", RFC 4794,
              December 2006.

Appendix A.  Acknowledgments

   Many thanks to Bert Wijnen, Adrian Farrel, and Bill Fenner for their
   input on RFC 4020.  Thank you to Kireeti Kompella and Alex Zinin for
   authoring RFC4020.  Thank you to Adrian Farrel, Stewart Bryant, Leo
   Vegoda, John Klensin, Subramanian Moonesamy, Loa Andersson, Tom
   Petch, Robert Sparks and Eric Rosen for their reviews of this

Author's Address

   Michelle Cotton
   Internet Corporation for Assigned Names and Numbers
   12025 Waterfront Drive, Suite 300
   Los Angeles, CA  90094-2536
   United States of America

   Phone: +1-310-823-5800

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