Network Working Group Internet Activities Board

Request for Comments: 1083 December 1988


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). An overview of the standards procedures is presented first, followed by discussions of the standardization process and the RFC document series, then the explanation of the terms is presented, the lists of protocols in each stage of standardization follows, and finally pointers to references and contacts for further information.

This memo is issued quarterly, please be sure the copy you are reading is dated within the last three months. 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 memo after 31-March-89.

Distribution of this memo is unlimited.

1. Overview of Standards Procedures

The Internet Activities Board maintains a list of documents that define standards for the Internet protocol suite. It provides these 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.

Protocol standards may be proposed by anyone in the Internet community, by writing and submitting an RFC. In general, any proposed protocol will be reviewed or developed in the context of some Task Force of the IAB, or some working group within that Task Force. The IAB will assign a proposed protocol to a working group if official delegation is necessary.

The recommendation of the working group or task force is given major consideration in the decision by the IAB to assign a state and status to the protocol. The general policy is not to designate a protocol as an official standard until there is implementation experience with it.

In cases where there is uncertainty as to the proper decision concerning a protocol, the IAB may convene a special review committee consisting of interested parties from the working group and members of the IAB itself, with the purpose of recommending some explicit action to the IAB.

It is possible to proceed with widespread implementation of a standard without the approval of the IAB. For example, some vendor standards have become very important to the Internet community even though they have not been proposed or reviewed 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 term "standard" in any RFC to only those protocols which the IAB has approved.

2. The Standardization Process

Anyone can invent a protocol, document it, implement it, test it, and so on. The IAB believes that it is very useful to document a protocol at an early stage to promote suggestions from others interested in the functionality the of protocol and from those interested in protocol design. Once a protocol is implemented and tested it is useful to report the results. The RFC document series is the preferred place for publishing these protocol documents and testing results.

The IAB encourages the documenting of every protocol developed in the Internet (that is, the publication of the protocol specification as an RFC), even if it is never intended that the protocol become an Internet standard. A protocol that is not intended to become a standard is called "experimental".

Protocols that are intended to become standards are first designated as "proposed" protocols. It is expected that while in this state the protocol will be implemented and tested by several groups. It is likely that an improved version of the protocol will result from this activity.

Once a proposed protocol has become stable and has a sponsor (an individual willing to speak for the protocol to the IAB) it may advance to the "draft standard" state. In this state, it should be reviewed by the entire Internet community. This draft standard state is essentially a warning to the community that unless an objection is raised or a flaw is found this protocol will become a "standard".

Once a protocol has been a draft standard for a sufficient time (usually 6 months) without serious objections the IAB may act to declare the protocol an official Internet standard.

Some protocols have been superseded by better protocols or are otherwise unused. Such protocols are designated "historic".

In addition to a state (like proposed or standard) a protocol is also assigned a status. A protocol can be required, meaning that all systems in the Internet must implement it. For example, the Internet Protocol (IP) is required. A protocol may be recommended, meaning that systems should implement this protocol. A protocol may be elective, meaning that systems may implement this protocol; that is, if (and only if) the functionality of this protocol is needed or useful for a system it must use this protocol to provide the functionality. A protocol may be termed not recommended if it is not intended to be generally implemented; for example, experimental or historic protocols.

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, multi-user hosts. It is not necessary for a gateway to implement TCP and the protocols that use TCP (though it may be useful). It is expected that general purpose hosts will implement at least IP (including ICMP), TCP and UDP, Telnet, FTP, SMTP, Mail, and the Domain Name System (DNS).

3. The Request for Comments Documents

The documents called Request for Comments (or RFCs) are the working notes of 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. 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 form the task forces, individual technical experts, or the RFC Editor, as appropriate.

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 to refer to for the current specification of each protocol.

The RFCs are available from the Network Information Center at SRI International. For more information about obtaining RFCs see the contact information at the end of this memo.

4. 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 Official 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.

4.1. 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-1010.

Another document, Internet Numbers, lists the assigned IP network numbers, and the autonomous system numbers. Internet Numbers was most recently issued as RFC-1062.

4.2. Official Protocols

This document list the protocols and describes any known problems and ongoing experiments. Official Protocols was recently issued as RFC- 1011.

4.3. Gateway Requirements

This document reviews the specifications that apply to gateways and supplies guidance and clarification for any ambiguities. Gateway Requirement was recently issued as RFC-1009.

4.4. Host Requirements

This document reviews the specifications that apply to hosts and supplies guidance and clarification for any ambiguities. Host Requirements is in preparation and will be issued soon.

5. Explanation of Terms

There are two independent categorizations of protocols. The first is the state of standardization which is one of "standard", "draft standard", "proposed", "experimental", or "historic". The second is the status of this protocol which is one of "required", "recommended", "elective", or "not recommended". One could expect a particular protocol to move along the scale of status from elective to required at the same time as it moves along the scale of standardization from proposed to standard.

At any given time a protocol is a cell of the following matrix. Protocols are likely to be in cells in about the following proportions (indicated by the number of Xs). Most will be on the main diagonal. A new protocol is most likely to start in the (proposed, elective) cell, or the (experimental, not recommended) cell.

                     Req   Rec   Ele   Not
           Std     | XXX |  XX |  X  |     |
           Draft   |     |  X  |  XX |     |
           Prop    |     |     | XXX |  X  |
           Expr    |     |     |  X  | XXX |
           Hist    |     |     |     | XXX |

Some protocol are particular to hosts and some to gateways; a few protocols are used in both. The definitions of the terms below will refer to a "system" which is either a host or a gateway (or both). It should be clear from the context of the particular protocol which types of systems are intended.

5.1. Definitions

5.1.1. Standard Protocol

The IAB has established this as an official standard protocol for the Internet. These are separated into two groups: (1) IP protocol and above, protocols that apply to the whole Internet; and (2) network-specific protocols, generally specifications of how to do IP on particular types of networks.

5.1.2. Draft Standard Protocol

The IAB is actively considering this protocol as a possible Standard Protocol. Substantial and widespread testing and comment is desired. Comments and test results should be submitted to the IAB. There is a possibility that changes will be made in a Draft Standard Protocol before it becomes a Standard Protocol.

5.1.3. Proposed Protocol

These are protocol proposals that may be considered by the IAB for standardization in the future. Implementation and testing by several groups is desirable. Revisions of the protocol specification are likely.

5.1.4. Experimental Protocol

A system should not implement an experimental protocol unless it is participating in the experiment and has coordinated its use of the protocol with the developer of the protocol.

Typically, experimental protocols are those that are developed as part of a specific ongoing research project not related to an operational service offering. While they may be proposed as a service protocol at a later stage, and thus become proposed, draft, and then standard protocols, the designation of a protocol as experimental is meant to suggest that the protocol, although perhaps mature, is not intended for operational use.

5.1.5. Historic Protocol

These are protocols that are unlikely to ever become standards in the Internet either because they have been superseded by later developments or due to lack of interest. These are protocols that are at an evolutionary dead end.

5.1.6. Required Protocol

All systems must implement the required protocols.

5.1.7. Recommended Protocol

All systems should implement the recommended protocols.

5.1.8. Elective Protocol

A system may or may not implement an elective protocol. The general notion is that if you are going to do something like this, you must do exactly this.

5.1.9. Not Recommended Protocol

These protocols are not recommended for general use. This may be because of their limited functionality, specialized nature, or experimental or historic state.

6. The Protocols

6.1. Standard Protocols

Protocol   Name                                      Status          RFC
--------   ----                                      ------          ---
           Assigned Numbers                          Required       1010
           Gateway Requirements                      Required       1009
IP         Internet Protocol                         Required        791
            as amended by:
             IP Subnet Extension                     Required        950
             IP Broadcast Datagrams                  Required        919
             IP Broadcast Datagrams with Subnets     Required        922
ICMP       Internet Control Message Protocol         Required        792
UDP        User Datagram Protocol                    Recommended     768
TCP        Transmission Control Protocol             Recommended     793
DOMAINS    Domain Name System                     Recommended  1034,1035
TELNET     Telnet Protocol                           Recommended     854
FTP        File Transfer Protocol                    Recommended     959
SMTP       Simple Mail Transfer Protocol             Recommended     821
MAIL       Format of Electronic Mail Messages        Recommended     822
EGP        Exterior Gateway Protocol                 Recommended     904
NETBIOS    NetBIOS Services Protocol                 Elective  1001,1002
ECHO       Echo Protocol                             Recommended     862
DISCARD    Discard Protocol                          Elective        863
CHARGEN    Character Generator Protocol              Elective        864
QUOTE      Quote of the Day Protocol                 Elective        865
USERS      Active Users Protocol                     Elective        866
DAYTIME    Daytime Protocol                          Elective        867
TIME       Time Server Protocol                      Elective        868

6.2. Specific Standard Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
ARP        Address Resolution Protocol              Elective         826
RARP       A Reverse Address Resolution Protocol    Elective         903
IP-ARPA    Internet Protocol on ARPANET             Elective    BBN 1822
IP-WB      Internet Protocol on Wideband Network    Elective         907
IP-X25     Internet Protocol on X.25 Networks       Elective         877
IP-E       Internet Protocol on Ethernet Networks   Elective         894
IP-EE      Internet Protocol on Exp. Ethernet Nets  Elective         895
IP-IEEE    Internet Protocol on IEEE 802            Elective        1042
IP-DC      Internet Protocol on DC Networks         Elective         891
IP-HC      Internet Protocol on Hyperchannnel       Elective        1044
IP-ARC     Internet Protocol on ARCNET              Elective        1051
IP-SLIP    Transmission of IP over Serial Lines     Elective        1055

Note:  It is expected that a system will support one or more physical
networks and for each physical network supported the appropriate
protocols from the above list must be supported.  That is, it is
elective to support any particular type of physical network, and for the
physical networks actually supported it is required that they be
supported exactly according to the protocols in the above list.

6.3. Draft Standard Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
SNMP       Simple Network Monitoring Protocol       Recommended     1067
MIB        Management Information Base              Recommended     1066
SMI        Structure of Management Information      Recommended     1065
NTP        Network Time Protocol                    Elective        1059
IGMP       Internet Group Multicast Protocol        Recommended     1054
BOOTP      Bootstrap Protocol                       Recommended 951,1048

6.4. Proposed Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
VMTP       Versatile Message Transaction Protocol   Elective        1045
RIP        Routing Information Protocol             Elective        1058
SUN-RPC    Remote Procedure Call Protocol           Elective        1057
PCMAIL     Pcmail Transport Protocol                Elective        1056
NFILE      A File Access Protocol                   Elective        1037
           Mapping between X.400 and RFC-822        Elective    987,1026
STATSRV    Statistics Server                        Elective         996
NNTP       Network News Transfer Protocol           Elective         977
NICNAME    WhoIs Protocol                           Elective         954
HOSTNAME   HOSTNAME Protocol                        Elective         953
POP2       Post Office Protocol                     Elective         937
SFTP       Simple File Transfer Protocol            Elective         913
RLP        Resource Location Protocol               Elective         887
RTELNET    Remote Telnet Service                    Elective         818
TFTP       Trivial File Transfer Protocol           Elective         783
FINGER     Finger Protocol                          Elective         742
SUPDUP     SUPDUP Protocol                          Elective         734
NETED      Network Standard Text Editor             Elective         569
RJE        Remote Job Entry                         Elective         407

6.5. Experimental Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
IP-MTU     IP MTU Discovery Options                 Not Recommended 1063
NETBLT     Bulk Data Transfer Protocol              Not Recommended  998
IMAP2      Interactive Mail Access Protocol         Not Recommended 1064
COOKIE-JAR Authentication Scheme                    Not Recommended 1004
IRTP       Internet Reliable Transaction Protocol   Not Recommended  938
AUTH       Authentication Service                   Not Recommended  931
RATP       Reliable Asynchronous Transfer Protocol  Not Recommended  916
THINWIRE   Thinwire Protocol                        Not Recommended  914
LDP        Loader Debugger Protocol                 Not Recommended  909
RDP        Reliable Data Protocol                   Not Recommended  908
ST         Stream Protocol                       Not Recommended IEN 119
NVP-II     Network Voice Protocol               Not Recommended ISI memo

6.6. Historic Protocols

Protocol   Name                                     Status           RFC
--------   ----                                     ------           ---
SGMP       Simple Gateway Monitoring Protocol       Not Recommended 1028
HMP        Host Monitoring Protocol                 Not Recommended  869
GGP        Gateway Gateway Protocol                 Not Recommended  823
CLOCK      DCNET Time Server Protocol               Not Recommended  778
MPM        Internet Message Protocol                Not Recommended  759
NETRJS     Remote Job Service                       Elective         740
XNET       Cross Net Debugger                       Elective     IEN 158
NAMESERVER Host Name Server Protocol             Not Recommended IEN 116
MUX        Multiplexing Protocol                 Not Recommended IEN  90
GRAPHICS   Graphics Protocol                  Not Recommended  NIC 24308

7. Contacts

7.1. Internet Activities Board Contact


         Jon Postel
         Deputy Internet Architect
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

Please send your comments about this list of protocols and especially about the Draft Standard Protocols to the Internet Activities Board care of the Deputy Internet Architect.

7.2. Internet Assigned Numbers Authority Contact


         Joyce K. Reynolds
         Internet Assigned Numbers Authority
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

The protocol standards are managed for the IAB by the Internet Assigned Numbers Authority.

Please refer to the documents "Assigned Numbers" (RFC-1010) and "Official Internet Protocols" (RFC-1011) for further information about the status of protocol documents. There are two documents that summarize the requirements for host and gateways in the Internet, "Host Requirements" (RFC in preparation) and "Gateway Requirements" (RFC-1009).

How to obtain the most recent edition of this "IAB Official Protocol Standards" memo:

The file "in-notes/iab-standards.txt" may be copied via FTP from the VENERA.ISI.EDU computer using the FTP username "anonymous" and FTP password "guest".

7.3. Request for Comments Editor Contact


         Jon Postel
         RFC Editor
         USC Information Sciences Institute
         4676 Admiralty Way
         Marina del Rey, CA  90292-6695

Documents may be submitted via electronic mail to the RFC Editor for consideration for publication as RFC. If you are not familiar with the format or style requirements please request the "Instructions for RFC Authors". In general, the style of any recent RFC may be used as a guide.

7.4. The Network Information Center and Requests for Comments Contact


         SRI International
         DDN Network Information Center
         333 Ravenswood Avenue
         Menlo Park, CA  94025

The Network Information Center (NIC) provides many information services for the Internet community. Among them is maintaining the Requests for Comments (RFC) library.

RFCs can be obtained via FTP from SRI-NIC.ARPA with the pathname RFC:RFCnnnn.TXT where "nnnn" refers to the number of the RFC. A list of all RFCs may be obtained by copying the file RFC:RFC-INDEX.TXT. Log in with FTP username ANONYMOUS and password GUEST.

The NIC also provides an automatic mail service for those sites which cannot use FTP. Address the request to SERVICE@SRI-NIC.ARPA and in the subject field of the message indicate the RFC number, as in "Subject: RFC nnnn".

How to obtain the most recent edition of this "IAB Official Protocol Standards" memo:

The file RFC:IAB-STANDARDS.TXT may be copied via FTP from the SRI-NIC.ARPA computer following the same procedures used to obtain RFCs.

Author's Address:

Jon Postel
USC/Information Sciences Institute
4676 Admiralty Way
Marina del Rey, CA 90292


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