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Internet Engineering Task Force (IETF)                         M. CottonRequest for Comments: 7120                                         ICANNBCP: 100                                                    January 2014Obsoletes:4020Category: Best Current PracticeISSN: 2070-1721Early IANA Allocation of Standards Track Code PointsAbstract   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, which would   normally trigger code point allocation.  The procedures in this   document are intended to apply only to IETF Stream documents.   This document obsoletesRFC 4020.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 represents the consensus of the IETF community.  It has   received public review and has been approved for publication by the   Internet Engineering Steering Group (IESG).  Further information on   BCPs is available inSection 2 of RFC 5741.   Information about the current status of this document, any errata,   and how to provide feedback on it may be obtained athttp://www.rfc-editor.org/info/rfc7120.Cotton                    Best Current Practice                 [Page 1]

RFC 7120                  Early IANA Allocation             January 2014Copyright Notice   Copyright (c) 2014 IETF Trust and the persons identified as the   document authors.  All rights reserved.   This document is subject toBCP 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.Table of Contents1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .32.  Conditions for Early Allocation . . . . . . . . . . . . . . . .43.  Process for Early Allocation  . . . . . . . . . . . . . . . . .43.1.  Request . . . . . . . . . . . . . . . . . . . . . . . . . .53.2.  Follow-Up . . . . . . . . . . . . . . . . . . . . . . . . .53.3.  Expiry  . . . . . . . . . . . . . . . . . . . . . . . . . .64.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . .75.  Security Considerations . . . . . . . . . . . . . . . . . . . .76.  References  . . . . . . . . . . . . . . . . . . . . . . . . . .86.1.  Normative References  . . . . . . . . . . . . . . . . . . .86.2.  Informative References  . . . . . . . . . . . . . . . . . .8Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . . .9Cotton                    Best Current Practice                 [Page 2]

RFC 7120                  Early IANA Allocation             January 20141.  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 IETF policies for IANA   allocation of protocol parameters are described inRFC 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 present a problem in situations where   implementation and/or deployment experience are desired or required   before the document becomes an RFC.   To break the deadlock, document authors often choose some "seemingly   unused" code points, often by selecting the next available value from   the registry; this is problematic because 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 that finding a better solution is worthwhile.  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.Cotton                    Best Current Practice                 [Page 3]

RFC 7120                  Early IANA Allocation             January 2014   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 obsoletesRFC 4020 and includes other   registration procedures regarding the types of registries that can   qualify for early allocation.  The procedures in this document are   intended to apply only to IETF Stream documents.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,       requests for early assignment of code points from a       "Specification Required" registry are allowed if the       specification will be published as an RFC.   b.  The format, semantics, processing, and other rules related to       handling 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 Area Directors (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.Cotton                    Best Current Practice                 [Page 4]

RFC 7120                  Early IANA Allocation             January 2014   The processes described below assume that the document in question is   the product of an IETF Working Group (WG).  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 to which document they should       be assigned.   2.  The WG chairs determine whether the conditions for early       allocations described inSection 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 for the given document.   4.  If steps 2) and 3) are satisfied, the WG chairs request approval       from 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       public.   Note that Internet-Drafts should not include a specific value of a   code point until IANA has completed the early allocation for this   value.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.Cotton                    Best Current Practice                 [Page 5]

RFC 7120                  Early IANA Allocation             January 2014   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 (seeSection 3.3   for more 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 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 inSection 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 described inSection 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.Cotton                    Best Current Practice                 [Page 6]

RFC 7120                  Early IANA Allocation             January 2014   Implementers and deployers need to be aware that deprecation and   de-allocation could take place at any time after expiry; therefore,   an expired early allocation is best considered as deprecated.   It is not IANA's responsibility to track the status of allocations,   their expirations, 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 is awaiting   publication 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 has updated   impacted registries by removing any such markings.5.  Security Considerations   It is important to keep in mind that denial-of-service attacks on   IANA are possible as a result of the processes defined 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 potential   attacks, but they are subject to scrutiny by IANA to ensure that they   work.  IANA may at any time request that the IESG suspend the   procedures described in this document.   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 pressured to obtain an early allocation for a   protocol extension for a particular company or for another Standards   Development Organization 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 safeguard, and ADs with any concern are strongly   recommended to escalate the issue for IESG-wide discussion.Cotton                    Best Current Practice                 [Page 7]

RFC 7120                  Early IANA Allocation             January 20146.  References6.1.  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.Cotton                    Best Current Practice                 [Page 8]

RFC 7120                  Early IANA Allocation             January 2014Appendix A.  Acknowledgments   Many thanks to Bert Wijnen, Adrian Farrel, and Bill Fenner for their   input onRFC 4020.  Thank you to Kireeti Kompella and Alex Zinin for   authoringRFC 4020.  Thank you to Adrian Farrel, Stewart Bryant, Leo   Vegoda, John Klensin, Subramanian Moonesamy, Loa Andersson, Tom   Petch, Robert Sparks, Eric Rosen, Amanda Baber, and Pearl Liang for   their reviews of this document.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   EMail: michelle.cotton@icann.org   URI:http://www.icann.org/Cotton                    Best Current Practice                 [Page 9]