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Network Working Group                                      P. Nesser, IIRequest for Comments: 3789                    Nesser & Nesser ConsultingCategory: Informational                                A. Bergstrom, Ed.                                              Ostfold University College                                                               June 2004Introduction to the Survey of IPv4 Addresses inCurrently Deployed IETF Standards Track and Experimental DocumentsStatus of this Memo   This memo provides information for the Internet community.  It does   not specify an Internet standard of any kind.  Distribution of this   memo is unlimited.Copyright Notice   Copyright (C) The Internet Society (2004).Abstract   This document is a general overview and introduction to the v6ops   IETF workgroup project of documenting all usage of IPv4 addresses in   IETF standards track and experimental RFCs.  It is broken into seven   documents conforming to the current IETF areas.  It also describes   the methodology used during documentation, which types of RFCs have   been documented, and provides a concatenated summary of results.Table of Contents1.0.  Introduction . . . . . . . . . . . . . . . . . . . . . . . .21.1.  Short Historical Perspective . . . . . . . . . . . . .21.2.  An Observation on the Classification of Standards. . .32.0.  Methodology. . . . . . . . . . . . . . . . . . . . . . . . .42.1.  Scope. . . . . . . . . . . . . . . . . . . . . . . . .43.0.  Summary of Results . . . . . . . . . . . . . . . . . . . . .53.1.  Application Area Specifications. . . . . . . . . . . .53.2.  Internet Area Specifications . . . . . . . . . . . . .53.3.  Operations and Management Area Specifications. . . . .63.4.  Routing Area Specifications. . . . . . . . . . . . . .63.5.  Security Area Specifications . . . . . . . . . . . . .63.6.  Sub-IP Area Specifications . . . . . . . . . . . . . .63.7.  Transport Area Specifications. . . . . . . . . . . . .7   4.0.  Discussion of "Long Term" Stability of Addresses on         Protocols. . . . . . . . . . . . . . . . . . . . . . . . . .75.0.  Security Considerations. . . . . . . . . . . . . . . . . . .86.0.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . .8Nesser II & Bergstrom        Informational                      [Page 1]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 20047.0.  References . . . . . . . . . . . . . . . . . . . . . . . . .87.1.  Normative References . . . . . . . . . . . . . . . . .88.0.  Authors' Addresses . . . . . . . . . . . . . . . . . . . . .99.0.  Full Copyright Statement . . . . . . . . . . . . . . . . . .101.0.  Introduction   This document is the introduction to a document set aiming to   document all usage of IPv4 addresses in IETF standards.  In an effort   to have the information in a manageable form, it has been broken into   7 documents, conforming to the current IETF areas (Application [1],   Internet [2], Operations and Management [3], Routing [4], Security   [5], Sub-IP [6], and Transport [7]).  It also describes the   methodology used during documentation, which types of RFCs that have   been documented, and provides a concatenated summary of results.1.1.  Short Historical Perspective   There are many challenges that face the Internet Engineering   community.  The foremost of these challenges has been the scaling   issue: how to grow a network that was envisioned to handle thousands   of hosts to one that will handle tens of millions of networks with   billions of hosts.  Over the years, this scaling problem has been   managed, with varying degrees of success, by changes to the network   layer and to routing protocols.  (Although largely ignored in the   changes to network layer and routing protocols, the tremendous   advances in computational hardware during the past two decades have   been of significant benefit in management of scaling problems   encountered thus far.)   The first "modern" transition to the network layer occurred during   the early 1980's, moving from the Network Control Protocol (NCP) to   IPv4.  This culminated in the famous "flag day" of January 1, 1983.   IP Version 4 originally specified an 8 bit network and 24 bit host   addresses, as documented inRFC 760.  A year later, IPv4 was updated   inRFC 791 to include the famous A, B, C, D, and E class system.   Networks were growing in such a way that it was clear that a   convention for breaking networks into smaller pieces was needed.  In   October of 1984RFC 917 was published formalizing the practice of   subnetting.   By the late 1980's, it was clear that the current exterior routing   protocol used by the Internet (EGP) was insufficiently robust to   scale with the growth of the Internet.  The first version of BGP was   documented in 1989 inRFC 1105.Nesser II & Bergstrom        Informational                      [Page 2]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 2004   Yet another scaling issue, exhaustion of the class B address space   became apparent in the early 1990s.  The growth and commercialization   of the Internet stimulated organisations requesting IP addresses in   alarming numbers.  By May of 1992, over 45% of the Class B space had   been allocated.  In early 1993RFC 1466 was published, directing   assignment of blocks of Class C's be given out instead of Class B's.   This temporarily circumvented the problem of address space   exhaustion, but had a significant impact of the routing   infrastructure.   The number of entries in the "core" routing tables began to grow   exponentially as a result ofRFC 1466.  This led to the   implementation of BGP4 and CIDR prefix addressing.  This may have   circumvented the problem for the present, but they continue to pose   potential scaling issues.   Growth in the population of Internet hosts since the mid-1980s would   have long overwhelmed the IPv4 address space if industry had not   supplied a circumvention in the form of Network Address Translators   (NATs).  To do this, the Internet has watered down the underlying   "End-to-End" principle.   In the early 1990's, the IETF was aware of these potential problems   and began a long design process to create a successor to IPv4 that   would address these issues.  The outcome of that process was IPv6.   The purpose of this document is not to discuss the merits or problems   of IPv6.  That debate is still ongoing and will eventually be decided   on how well the IETF defines transition mechanisms and how industry   accepts the solution.  The question is not "should," but "when."1.2.  An Observation on the Classification of Standards   It has become clear during the course of this investigation that   there has been little management of the status of standards over the   years.  Some attempt has been made by the introduction of the   classification of standards into Full, Draft, Proposed, Experimental,   and Historic.  However, there has not been a concerted effort to   actively manage the classification for older standards.  Standards   are only classified as Historic when either a newer version of the   protocol is deployed and it is randomly noticed that an RFC describes   a long dead protocol, or a serious flaw is discovered in a protocol.   Another issue is the status of Proposed Standards.  Since this is the   entry level position for protocols entering the standards process,   many old protocols or non-implemented protocols linger in this status   indefinitely.  This problem also exists for Experimental RFCs.   Similarly, the problem exists for the Best Current Practices (BCP)   and For You Information (FYI) series of documents.Nesser II & Bergstrom        Informational                      [Page 3]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 2004   To exemplify this point, there are 61 Full Standards, only 4 of which   have been reclassified to Historic.  There are 65 Draft Standards,   611 Proposed Standards, and 150 Experimental RFCs, of which only 66   have been reclassified as Historic.  That is a rate of less than 8%.   It should be obvious that in the more that 30 years of protocol   development and documentation, there should be at least as many (if   not a majority of) protocols that have been retired compared to the   ones that are currently active.   Please note that there is occasionally some confusion of the meaning   of a "Historic" classification.  It does NOT necessarily mean that   the protocol is not being used.  A good example of this concept is   the Routing Information Protocol(RIP) version 1.  There are many   thousands of sites using this protocol even though it has Historic   status.  There are potentially hundreds of otherwise classified RFC's   that should be reclassified.2.0.  Methodology   To perform this study, each class of IETF standards are investigated   in order of maturity:  Full, Draft, and Proposed, as well as   Experimental.  Informational and BCP RFCs are not addressed.  RFCs   that have been obsoleted by either newer versions or because they   have transitioned through the standards process are not covered.   RFCs which have been classified as Historic are also not included.   Please note that a side effect of this choice of methodology is that   some protocols that are defined by a series of RFC's that are of   different levels of standards maturity are covered in different spots   in the document.  Likewise, other natural groupings (i.e., MIBs, SMTP   extensions, IP over FOO, PPP, DNS, etc.) could easily be imagined.2.1.  Scope   The procedure used in this investigation is an exhaustive reading of   the applicable RFC's.  This task involves reading approximately   25,000 pages of protocol specifications.  To compound this, it was   more than a process of simple reading.  It was necessary to attempt   to understand the purpose and functionality of each protocol in order   to make a proper determination of IPv4 reliability.  The author has   made every effort to produce as complete a document set as possible,   but it is likely that some subtle (or perhaps not so subtle)   dependence was missed.  The author encourages those familiar   (designers, implementers or anyone who has an intimate knowledge)   with any protocol to review the appropriate sections and make   comments.Nesser II & Bergstrom        Informational                      [Page 4]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 20043.0.  Summary of Results   In the initial survey of RFCs, 173 positives were identified out of a   total of 877, broken down as follows:         Standards:                        30 out of  68 or 44.12%         Draft Standards:                  16 out of  68 or 23.53%         Proposed Standards:               98 out of 597 or 16.42%         Experimental RFCs:                29 out of 144 or 20.14%   Of those identified, many require no action because they document   outdated and unused protocols, while others are active document   protocols being updated by the appropriate working groups (SNMP MIBs   for example).   Additionally, there are many instances of standards that should be   updated but do not cause any operational impact (STD 3/RFCs 1122 and   1123 for example) if they are not updated.   In this statistical survey, a positive is defined as a RFC containing   an IPv4 dependency, regardless of context.3.1.  Application Area Specifications   In the initial survey of RFCs, 34 positives were identified out of a   total of 257, broken down as follows:         Standards:                         1 out of  20 or  5.00%         Draft Standards:                   4 out of  25 or 16.00%         Proposed Standards:               19 out of 155 or 12.26%         Experimental RFCs:                10 out of  57 or 17.54%   For more information, please look at [1].3.2.  Internet Area Specifications   In the initial survey of RFCs, 52 positives were identified out of a   total of 186, broken down as follows:         Standards:                        17 out of  24 or 70.83%         Draft Standards:                   6 out of  20 or 30.00%         Proposed Standards:               22 out of 111 or 19.91%         Experimental RFCs:                 7 out of  31 or 22.58%   For more information, please look at [2].Nesser II & Bergstrom        Informational                      [Page 5]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 20043.3.  Operations and Management Area Specifications   In the initial survey of RFCs, 36 positives were identified out of a   total of 153, broken down as follows:         Standards:                         6 out of  15 or 40.00%         Draft Standards:                   4 out of  15 or 26.67%         Proposed Standards:               26 out of 112 or 23.21%         Experimental RFCs:                 0 out of  11 or  0.00%   For more information, please look at [3].3.4.  Routing Area Specifications   In the initial survey of RFCs, 23 positives were identified out of a   total of 46, broken down as follows:         Standards:                         3 out of  3 or 100.00%         Draft Standards:                   1 out of  3 or  33.33%         Proposed Standards:               13 out of 29 or  44.83%         Experimental RFCs:                 6 out of 11 or  54.54%   For more information, please look at [4].3.5.  Security Area Specifications   In the initial survey of RFCs, 4 positives were identified out of a   total of 124, broken down as follows:         Standards:                         0 out of   1 or  0.00%         Draft Standards:                   1 out of   3 or 33.33%         Proposed Standards:                1 out of 102 or  0.98%         Experimental RFCs:                 2 out of  18 or 11.11%   For more information, please look at [5].3.6.  Sub-IP Area Specifications   In the initial survey of RFCs, 0 positives were identified out of a   total of 7, broken down as follows:         Standards:                         0 out of  0 or  0.00%         Draft Standards:                   0 out of  0 or  0.00%         Proposed Standards:                0 out of  6 or  0.00%         Experimental RFCs:                 0 out of  1 or  0.00%   For information about the Sub-IP Area standards, please look at [6].Nesser II & Bergstrom        Informational                      [Page 6]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 20043.7.  Transport Area Specifications   In the initial survey of RFCs, 24 positives were identified out of a   total of 104, broken down as follows:         Standards:                         3 out of  5 or 60.00%         Draft Standards:                   0 out of  2 or  0.00%         Proposed Standards:               17 out of 82 or 20.73%         Experimental RFCs:                 4 out of 15 or 26.67%   For more information, please look at [7].4.0.  Discussion of "Long Term" Stability of Addresses on Protocols   In attempting this analysis, it was determined that a full scale   analysis is well beyond the scope of this document.  Instead, a short   discussion is presented on how such a framework might be established.   A suggested approach would be to do an analysis of protocols based on   their overall function, similar (but not strictly) to the OSI network   reference model.  It might be more appropriate to frame the   discussion in terms of the different Areas of the IETF.   The problem is fundamental to the overall architecture of the   Internet and its future.  One of the stated goals of the IPng (now   IPv6) was "automatic" and "easy" address renumbering.  An additional   goal is "stateless autoconfiguration."  To these ends, a substantial   amount of work has gone into the development of such protocols as   DHCP and Dynamic DNS.  This goes against the Internet age-old "end-   to-end principle."   Most protocol designs implicitly count on certain underlying   principles that currently exist in the network.  For example, the   design of packet switched networks allows upper level protocols to   ignore the underlying stability of packet routes.  When paths change   in the network, the higher level protocols are typically unaware and   uncaring.  This works well since whether the packet goes A-B-C-D-E-F   or A-B-X-Y-Z-E-F is of little consequence.   In a world where endpoints (i.e., A and F in the example above)   change at a "rapid" rate, a new model for protocol developers should   be considered.  It seems that a logical development would be a change   in the operation of the Transport layer protocols.  The current model   is essentially a choice between TCP and UDP, neither of which   provides any mechanism for an orderly handoff of the connection if   and when the network endpoint (IP) addresses change.  Perhaps a thirdNesser II & Bergstrom        Informational                      [Page 7]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 2004   major transport layer protocol should be developed, or perhaps   updated TCP and UDP specifications that include this function might   be a better solution.   There are many, many variables that would need to go into a   successful development of such a protocol.  Some issues to consider   are: timing principles; overlap periods as an endpoint moves from   address A, to addresses A and B (answers to both), to only B; delays   due to the recalculation of routing paths, etc...5.0.  Security Considerations   This memo examines the IPv6-readiness of specifications; this does   not have security considerations in itself.6.0.  Acknowledgements   The authors would like to acknowledge the support of the Internet   Society in the research and production of this document.   Additionally the author, Philip J. Nesser II, would like to thanks   his partner in all ways, Wendy M. Nesser.   The editor, Andreas Bergstrom, would like to thank Pekka Savola for   guidance and collection of comments for the editing of this document.   He would further like to thank Alan E. Beard, Jim Bound, Brian   Carpenter, and Itojun for valuable feedback on many points of this   document.7.0.  References7.1.  Normative References   [1]  Sofia, R. and P. Nesser, II, "Survey of IPv4 Addresses in        Currently Deployed IETF Application Area Standards",RFC 3795,        June 2004.   [2]  Mickles, C., Editor and P. Nesser, II, "Survey of IPv4 Addresses        in Currently Deployed IETF Internet Area Standards",RFC 3790,        June 2004.   [3]  Nesser, II, P. and A. Bergstrom, Editor, "Survey of IPv4        Addresses in Currently Deployed IETF Operations & Management        Area Standards",RFC 3796, June 2004.   [4]  Olvera, C. and P. Nesser, II, "Survey of IPv4 Addresses in        Currently Deployed IETF Routing Area Standards",RFC 3791, June        2004.Nesser II & Bergstrom        Informational                      [Page 8]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 2004   [5]  Nesser, II, P. and A. Bergstrom, Editor, "Survey of IPv4        Addresses in Currently Deployed IETF Security Area Standards",RFC 3792, June 2004.   [6]  Nesser, II, P. and A. Bergstrom, Editor, "Survey of IPv4        Addresses in Currently Deployed IETF Sub-IP Area Standards",RFC3793, June 2004.   [7]  Nesser, II, P. and A. Bergstrom, Editor, "Survey of IPv4        Addresses in Currently Deployed IETF Transport Area Standards",RFC 3794, June 2004.8.0.  Authors' Addresses   Please contact the authors with any questions, comments or   suggestions at:   Philip J. Nesser II   Principal   Nesser & Nesser Consulting   13501 100th Ave NE, #5202   Kirkland, WA 98034   Phone:  +1 425 481 4303   Fax:    +1 425 482 9721   EMail:  phil@nesser.com   Andreas Bergstrom, Editor   Ostfold University College   Rute 503 Buer   N-1766 Halden   Norway   EMail: andreas.bergstrom@hiof.noNesser II & Bergstrom        Informational                      [Page 9]

RFC 3789      Introduction to the IPv4 Address in the IETF     June 20049.0.  Full Copyright Statement   Copyright (C) The Internet Society (2004).  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 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.Nesser II & Bergstrom        Informational                     [Page 10]