rfc1200.txt

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Network Working Group                          Internet Activities Board
Request for Comments: 1200                             J. Postel, Editor
Obsoletes: RFCs 1140,                                         April 1991
     1100, 1083, 1130



                    IAB OFFICIAL PROTOCOL STANDARDS


Status of this Memo

   This memo describes the state of standardization of protocols used in
   the Internet as determined by the Internet Activities Board (IAB).
   Distribution of this memo is unlimited.

Table of Contents

   Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 2
   1.  The Standardization Process  . . . . . . . . . . . . . . . . 2
   2.  The Request for Comments Documents . . . . . . . . . . . . . 5
   3.  Other Reference Documents  . . . . . . . . . . . . . . . . . 6
   3.1.  Assigned Numbers . . . . . . . . . . . . . . . . . . . . . 6
   3.2.  Annotated Internet Protocols . . . . . . . . . . . . . . . 6
   3.3.  Gateway Requirements . . . . . . . . . . . . . . . . . . . 6
   3.4.  Host Requirements  . . . . . . . . . . . . . . . . . . . . 6
   3.5.  The MIL-STD Documents  . . . . . . . . . . . . . . . . . . 7
   4.  Explanation of Terms . . . . . . . . . . . . . . . . . . . . 7
   4.1.  Definitions of Protocol State  . . . . . . . . . . . . . . 8
   4.1.1.  Standard Protocol  . . . . . . . . . . . . . . . . . . . 8
   4.1.2.  Draft Standard Protocol  . . . . . . . . . . . . . . . . 9
   4.1.3.  Proposed Standard Protocol . . . . . . . . . . . . . . . 9
   4.1.4.  Experimental Protocol  . . . . . . . . . . . . . . . . . 9
   4.1.5.  Informational Protocol . . . . . . . . . . . . . . . . . 9
   4.1.6.  Historic Protocol  . . . . . . . . . . . . . . . . . . . 9
   4.2.  Definitions of Protocol Status . . . . . . . . . . . . . .10
   4.2.1.  Required Protocol  . . . . . . . . . . . . . . . . . . .10
   4.2.2.  Recommended Protocol . . . . . . . . . . . . . . . . .  10
   4.2.3.  Elective Protocol  . . . . . . . . . . . . . . . . . .  10
   4.2.4.  Limited Use Protocol . . . . . . . . . . . . . . . . .  10
   4.2.5.  Not Recommended Protocol . . . . . . . . . . . . . . .  10
   5.  The Standards Track  . . . . . . . . . . . . . . . . . . .  10
   5.1.  The RFC Processing Decision Table  . . . . . . . . . . .  10
   5.2.  The Standards Track Diagram  . . . . . . . . . . . . . .  12
   6.  The Protocols  . . . . . . . . . . . . . . . . . . . . . .  14
   6.1.  Recent Changes . . . . . . . . . . . . . . . . . . . . .  14
   6.1.1.  New RFCs . . . . . . . . . . . . . . . . . . . . . . .  14
   6.1.2.  Other Changes  . . . . . . . . . . . . . . . . . . . .  20



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   6.2.  Standard Protocols . . . . . . . . . . . . . . . . . . .  22
   6.3.  Network-Specific Standard Protocols  . . . . . . . . . .  23
   6.4.  Draft Standard Protocol  . . . . . . . . . . . . . . . .  24
   6.5.  Proposed Standard Protocol . . . . . . . . . . . . . . .  25
   6.6.  Experimental Protocol  . . . . . . . . . . . . . . . . .  26
   6.7.  Informational Protocol . . . . . . . . . . . . . . . . .  26
   6.8.  Historic Protocol  . . . . . . . . . . . . . . . . . . .  27
   7.  Contacts . . . . . . . . . . . . . . . . . . . . . . . . .  27
   7.1.  IAB, IETF, and IRTF Contacts . . . . . . . . . . . . . .  27
   7.1.1.  Internet Activities Board (IAB) Contact  . . . . . . .  27
   7.1.2.  Internet Engineering Task Force (IETF) Contact . . . .  28
   7.1.3.  Internet Research  Task Force (IETF) Contact . . . . .  28
   7.2.  Internet Assigned Numbers Authority (IANA) Contact . . .  28
   7.3.  Request for Comments Editor Contact  . . . . . . . . . .  29
   7.4.  Network Information Center Contact . . . . . . . . . . .  29
   7.5.  Other Sources for Requests for Comments  . . . . . . . .  30
   7.5.1.  NSF Network Service Center (NNSC)  . . . . . . . . . .  30
   7.5.2.  NSF Network Information Service (NIS)  . . . . . . . .  30
   7.5.3.  CSNET Coordination and Information Center (CIC)  . . .  31
   8.  Security Considerations  . . . . . . . . . . . . . . . . .  31
   9.  Author's Address . . . . . . . . . . . . . . . . . . . . .  31

Introduction

   Discussion of the standardization process and the RFC document series
   is presented first, followed by an explanation of the terms.
   Sections 6.2 - 6.8 contain the lists of protocols in each stage of
   standardization.  Finally come pointers to references and contacts
   for further information.

   This memo is intended to be issued quarterly; please be sure the copy
   you are reading is current.  Current copies may be obtained from the
   Network Information Center or from the Internet Assigned Numbers
   Authority (see the contact information at the end of this memo).  Do
   not use this edition after 30-Jun-91.

   See Section 6.1 for a description of recent changes.  In the official
   lists in sections 6.2 - 6.8, an asterisk (*) next to a protocol
   denotes that it is new to this document or has been moved from one
   protocol level to another.

1.  The Standardization Process

   The Internet Activities Board maintains this list of documents that
   define standards for the Internet protocol suite (see RFC-1160 for an
   explanation of the role and organization of the IAB and its
   subsidiary groups, the Internet Engineering Task Force (IETF) and the
   Internet Research Task Force (IRTF)).  The IAB provides these



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   standards with the goal of co-ordinating the evolution of the
   Internet protocols; this co-ordination has become quite important as
   the Internet protocols are increasingly in general commercial use.

   The majority of Internet protocol development and standardization
   activity takes place in the working groups of the Internet
   Engineering Task Force.

   Protocols which are to become standards in the Internet go through a
   series of states (proposed standard, draft standard, and standard)
   involving increasing amounts of scrutiny and experimental testing.
   At each step, the Internet Engineering Steering Group (IESG) of the
   IETF must make a recommendation for advancement of the protocol and
   the IAB must ratify it.  If a recommendation is not ratified, the
   protocol is remanded to the IETF for further work.

   To allow time for the Internet community to consider and react to
   standardization proposals, the IAB imposes a minimum delay of 4
   months before a proposed standard can be advanced to a draft standard
   and 6 months before a draft standard can be promoted to standard.

   It is general IAB practice that no proposed standard can be promoted
   to draft standard without at least two independent implementations
   (and the recommendation of the IESG).  Promotion from draft standard
   to standard generally requires operational experience and
   demonstrated interoperability of two or more implementations (and the
   recommendation of the IESG).

   In cases where there is uncertainty as to the proper decision
   concerning a protocol the IAB may convene a special review committee
   consisting of experts from the IETF, IRTF and the IAB with the
   purpose of recommending an explicit action to the IAB.

   Advancement of a protocol to proposed standard is an important step
   since it marks a protocol as a candidate for eventual standardization
   (it puts the protocol "on the standards track").  Advancement to
   draft standard is a major step which warns the community that, unless
   major objections are raised or flaws are discovered, the protocol is
   likely to be advanced to standard in six months.

   Some protocols have been superseded by better ones or are otherwise
   unused.  Such protocols are still documented in this memorandum with
   the designation "historic".

   Because the IAB believes it is useful to document the results of
   early protocol research and development work, some of the RFCs
   document protocols which are still in an experimental condition.  The
   protocols are designated "experimental" in this memorandum.  They



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   appear in this report as a convenience to the community and not as
   evidence of their standardization.

   Other protocols, such as those developed by other standards
   organizations, or by particular vendors, may be of interest or may be
   recommended for use in the Internet.  The specifications of such
   protocols may be published as RFCs for the convenience of the
   Internet community.  These protocols are labeled "informational" in
   this memorandum.

   In addition to the working groups of the IETF, protocol development
   and experimentation may take place as a result of the work of the
   research groups of the Internet Research Task Force, or the work of
   other individuals interested in Internet protocol development.  The
   IAB encourages the documentation of such experimental work in the RFC
   series, but none of this work is considered to be on the track for
   standardization until the IESG has made a recommendation to advance
   the protocol to the proposed standard state, and the IAB has approved
   this step.

   A few protocols have achieved widespread implementation without the
   approval of the IESG and the IAB.  For example, some vendor protocols
   have become very important to the Internet community even though they
   have not been recommended by the IESG or ratified by the IAB.
   However, the IAB strongly recommends that the IAB standards process
   be used in the evolution of the protocol suite to maximize
   interoperability (and to prevent incompatible protocol requirements
   from arising).  The IAB reserves the use of the terms "standard",
   "draft standard", and "proposed standard" in any RFC or other
   publication of Internet protocols to only those protocols which the
   IAB has approved.

   In addition to a state (like "Proposed Standard"), a protocol is also
   assigned a status, or requirement level, in this document.  The
   possible requirement levels ("Required", "Recommended", "Elective",
   "Limited Use", and "Not Recommended") are defined in Section 4.2.
   When a protocol is on the standards track, that is in the proposed
   standard, draft standard, or standard state (see Section 5), the
   status shown in Section 6 is the current status.  For a proposed or
   draft standard, however, the IAB will also endeavor to indicate the
   eventual status this protocol will have after adoption as a standard.

   Few protocols are required to be implemented in all systems; this is
   because there is such a variety of possible systems, for example,
   gateways, terminal servers, workstations, and multi-user hosts.  The
   requirement level shown in this document is only a one word label,
   which may not be sufficient to characterize the implementation
   requirements for a protocol in all situations.  For some protocols,



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   this document contains an additional status paragraph.  In addition,
   more detailed status information is contained in separate
   requirements documents (see Section 3).

2.  The Request for Comments Documents

   The documents called Request for Comments (or RFCs) are the working
   notes of the "Network Working Group", that is the Internet research
   and development community.  A document in this series may be on
   essentially any topic related to computer communication, and may be
   anything from a meeting report to the specification of a standard.

   Notice:

      All standards are published as RFCs, but not all RFCs specify
      standards.

   Anyone can submit a document for publication as an RFC.  Submissions
   must be made via electronic mail to the RFC Editor (see the contact
   information at the end of this memo).

   While RFCs are not refereed publications, they do receive technical
   review from the task forces, individual technical experts, or the RFC
   Editor, as appropriate.

   The RFC series comprises a wide range of documents, ranging from
   informational documents of general interests to specifications of
   standard Internet protocols.  In cases where submission is intended
   to document a proposed standard, draft standard, or standard
   protocol, the RFC Editor will publish the document only with the
   approval of both the IESG and the IAB.  For documents describing
   experimental work, the RFC Editor will notify the IESG before
   publication, allowing for the possibility of review by the relevant
   IETF working group or IRTF research group and provide those comments
   to the author.  See Section 5.1 for more detail.

   Once a document is assigned an RFC number and published, that RFC is
   never revised or re-issued with the same number.  There is never a
   question of having the most recent version of a particular RFC.
   However, a protocol (such as File Transfer Protocol (FTP)) may be
   improved and re-documented many times in several different RFCs.  It
   is important to verify that you have the most recent RFC on a
   particular protocol.  This "IAB Official Protocol Standards" memo is
   the reference for determining the correct RFC for the current
   specification of each protocol.

   The RFCs are available from the Network Information Center at SRI
   International, and a number of other sites.  For more information



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   about obtaining RFCs, see Sections 7.4 and 7.5.

3.  Other Reference Documents

   There are four other reference documents of interest in checking the
   current status of protocol specifications and standardization.  These
   are the Assigned Numbers, the Annotated Internet Protocols, the
   Gateway Requirements, and the Host Requirements.  Note that these
   documents are revised and updated at different times; in case of
   differences between these documents, the most recent must prevail.

   Also, one should be aware of the MIL-STD publications on IP, TCP,
   Telnet, FTP, and SMTP.  These are described in Section 3.5.

3.1.  Assigned Numbers

   This document lists the assigned values of the parameters used in the
   various protocols.  For example, IP protocol codes, TCP port numbers,
   Telnet Option Codes, ARP hardware types, and Terminal Type names.
   Assigned Numbers was most recently issued as RFC-1060.

   Another document, Internet Numbers, lists the assigned IP network
   numbers, and the autonomous system numbers.  Internet Numbers was
   most recently issued as RFC-1166.

3.2.  Annotated Internet Protocols

   This document lists the protocols and describes any known problems
   and ongoing experiments.  This document was most recently issued as
   RFC-1011.

3.3.  Gateway Requirements

   This document reviews the specifications that apply to gateways and
   supplies guidance and clarification for any ambiguities.  Gateway
   Requirements is RFC-1009.  A working group of the IETF is actively
   preparing a revision.

3.4.  Host Requirements

   This pair of documents reviews and updates the specifications that
   apply to hosts, and it supplies guidance and clarification for any
   ambiguities.  Host Requirements was issued as RFC-1122 and RFC-1123.