Network Working Group                          Internet Activities Board
Request for Comments: 1250                             J. Postel, Editor
Obsoletes: RFCs 1200,                                        August 1991
1100, 1083, 1130, 1140
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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

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

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6.2. Standard Protocols
6.3. Network-Specific Standard Protocols
6.4. Draft Standard Protocols
6.5. Proposed Standard Protocols
6.6. Telnet Options
6.7. Experimental Protocols
6.8. Informational Protocols
6.9. Historic Protocols
7. Contacts
7.1. IAB, IETF, and IRTF Contacts
7.1.1. Internet Activities Board (IAB) Contact
7.1.2. Internet Engineering Task Force (IETF) Contact
7.1.3. Internet Research Task Force (IRTF) Contact
7.2. Internet Assigned Numbers Authority (IANA) Contact
7.3. Request for Comments Editor Contact
7.4. Network Information Center Contact
7.5. Other Sources for Requests for Comments
8. Security Considerations
9. Author's Address


Discussion of the standardization process and the RFC document series is presented first, followed by an explanation of the terms. Sections 6.2 - 6.9 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-Nov-91.

See Section 6.1 for a description of recent changes. In the official lists in sections 6.2 - 6.9, 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 standards with the goal of co-ordinating the evolution of the Internet protocols; this co-ordination has become quite important as

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

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

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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.


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 about obtaining RFCs, see Sections 7.4 and 7.5.

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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.

3.5. The MIL-STD Documents

The Internet community specifications for IP (RFC-791) and TCP (RFC- 793) and the DoD MIL-STD specifications are intended to describe exactly the same protocols. Any difference in the protocols specified by these sets of documents should be reported to DCA and to

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the IAB. The RFCs and the MIL-STDs for IP and TCP differ in style and level of detail. It is strongly advised that the two sets of documents be used together, along with RFC-1122 and RFC-1123.

The IAB and the DoD MIL-STD specifications for the FTP, SMTP, and Telnet protocols are essentially the same documents (RFCs 765, 821, 854). The MIL-STD versions have been edited slightly. Note that the current Internet specification for FTP is RFC-959 (as modified by RFC-1123).

Note that these MIL-STD are now somewhat out of date. The Gateway Requirements (RFC-1009) and Host Requirements (RFC-1122, RFC-1123) take precedence over both earlier RFCs and the MIL-STDs.

          Internet Protocol (IP)                      MIL-STD-1777
          Transmission Control Protocol (TCP)         MIL-STD-1778
          File Transfer Protocol (FTP)                MIL-STD-1780
          Simple Mail Transfer Protocol (SMTP)        MIL-STD-1781
          Telnet Protocol and Options (TELNET)        MIL-STD-1782

These documents are available from the Naval Publications and Forms Center. Requests can be initiated by telephone, telegraph, or mail; however, it is preferred that private industry use form DD1425, if possible. These five documents are included in the 1985 DDN Protocol Handbook (available from the Network Information Center, see Section 7.4).

Naval Publications and Forms Center, Code 3015
5801 Tabor Ave
Philadelphia, PA 19120
Phone: 1-215-697-3321 (order tape)
1-215-697-4834 (conversation)

4. Explanation of Terms

There are two independent categorization of protocols. The first is the STATE of standardization, one of "standard", "draft standard", "proposed standard", "experimental", "informational" or "historic". The second is the STATUS (requirement level or applicability) of this protocol, one of "required", "recommended", "elective", "limited use", or "not recommended".

The status or requirement level is difficult to portray in a one word label. These status labels should be considered only as an indication, and a further description, or applicability statement, should be consulted.

When a protocol is advanced to proposed standard or draft standard,

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it is labeled with a current status and when possible, the IAB also notes the status that the protocol is expected to have when it reaches the standard state.

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


                     Req   Rec   Ele   Lim   Not
           Std     |  X  | XXX | XXX |     |     |
       S           +-----+-----+-----+-----+-----+
           Draft   |  X  |  X  | XXX |     |     |
       T           +-----+-----+-----+-----+-----+
           Prop    |     |  X  | XXX |  X  |     |
       A           +-----+-----+-----+-----+-----+
           Info    |     |  X  | XXX |  X  |  X  |
       T           +-----+-----+-----+-----+-----+
           Expr    |     |     |  X  | XXX |  X  |
       E           +-----+-----+-----+-----+-----+
           Hist    |     |     |     |  X  | XXX |

What is a "system"?

Some protocols 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.

4.1. Definitions of Protocol State

Every protocol listed in this document is assigned to a STATE of standardization: "standard", "draft standard", "proposed standard", "experimental", or "historic".

4.1.1. 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.

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4.1.2. Draft Standard Protocol

The IAB is actively considering this protocol as a possible Standard Protocol. Substantial and widespread testing and comment are 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.

4.1.3. Proposed Standard 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. Revision of the protocol specification is likely.

4.1.4. 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 an 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 standard, draft standard, and then standard protocols, the designation of a protocol as experimental may sometimes be meant to suggest that the protocol, although perhaps mature, is not intended for operational use.

4.1.5. Informational Protocol

Protocols developed by other standard organizations, or vendors, or that are for other reasons outside the purview of the IAB, may be published as RFCs for the convenience of the Internet community as informational protocols. Such protocols may in some cases also be recommended for use in the Internet by the IAB.

4.1.6. 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.

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4.2. Definitions of Protocol Status

This document lists a STATUS (requirement level or applicability) for each protocol. The status is one of "required",
"recommended", "elective", "limited use", or "not recommended".

4.2.1. Required Protocol

A system must implement the required protocols.

4.2.2. Recommended Protocol

A system should implement the recommended protocols.

4.2.3. 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. There may be several elective protocols in a general area, for example, there are several electronic mail protocols, and several routing protocols.

4.2.4. Limited Use Protocol

These protocols are for use in limited circumstances. This may be because of their experimental state, specialized nature, limited functionality, or historic state.

4.2.5. 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.

5. The Standards Track

This section discusses in more detail the procedures used by the RFC Editor and the IAB in making decisions about the labeling and publishing of protocols as standards.

5.1. The RFC Processing Decision Table

Here is the current decision table for processing submissions by the RFC Editor. The processing depends on who submitted it, and the status they want it to have.

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      |**************|               S O U R C E                 |
      | Desired      |    IAB   |   IESG   |   IRSG   |  Other   |
      | Status       |          |          |  or RG   |          |
      |              |          |          |          |          |
      | Standard     |  Publish |  Vote    |  Bogus   |  Bogus   |
      | or           |   (1)    |   (3)    |   (2)    |   (2)    |
      | Draft        |          |          |          |          |
      | Standard     |          |          |          |          |
      |              |          |          |          |          |
      |              |  Publish |  Vote    |  Refer   |  Refer   |
      | Proposed     |   (1)    |   (3)    |   (4)    |   (4)    |
      | Standard     |          |          |          |          |
      |              |          |          |          |          |
      |              |          |          |          |          |
      |              |  Publish |  Notify  |  Notify  |  Notify  |
      | Experimental |   (1)    |   (5)    |   (5)    |   (5)    |
      | Protocol     |          |          |          |          |
      |              |          |          |          |          |
      |              |          |          |          |          |
      | Information  |  Publish |Discretion|Discretion|Discretion|
      | or Opinion   |   (1)    |   (6)    |   (6)    |   (6)    |
      | Paper        |          |          |          |          |
      |              |          |          |          |          |

(1) Publish.

(2) Bogus. Inform the source of the rules. RFCs specifying Standard, or Draft Standard must come from the IAB, only.

(3) Vote by the IAB. If approved then do Publish (1), else do Refer (4).

(4) Refer to an Area Director for review by a WG. Expect to see the document again only after approval by the IESG and the IAB.

(5) Notify both the IESG and IRSG. If no concerns are raised in two weeks then do Discretion (6), else RFC Editor to resolve the concerns or do Refer (4).

(6) RFC Editor's discretion. The RFC Editor decides if a review

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is needed and if so by whom. RFC Editor decides to publish or not.

Of course, in all cases the RFC Editor can request or make minor changes for style, format, and presentation purposes.

The IESG has designated the IESG Secretary as its agent for forwarding documents with IESG approval and for registering concerns in response to notifications (5) to the RFC Editor. Documents from Area Directors or Working Group Chairs may be considered in the same way as documents from "other".

5.2. The Standards Track Diagram

There is a part of the STATUS and STATE categorization that is called the standards track. Actually, only the changes of state are significant to the progression along the standards track, though the status assignments may be changed as well.

The states illustrated by single line boxes are temporary states, those illustrated by double line boxes are long term states. A protocol will normally be expected to remain in a temporary state for several months (minimum four months for proposed standard, minimum six months for draft standard). A protocol may be in a long term state for many years.

A protocol may enter the standards track only on the recommendation of the IESG and by action of the IAB; and may move from one state to another along the track only on the recommendation of the IESG and by action of the IAB. That is, it takes both the IESG and the IAB to either start a protocol on the track or to move it along.

Generally, as the protocol enters the standards track a decision is made as to the eventual STATUS, requirement level or applicability (elective, recommended, or required) the protocol will have, although a somewhat less stringent current status may be assigned, and it then is placed in the the proposed standard STATE with that status. So the initial placement of a protocol is into state 1. At any time the STATUS decision may be revisited.

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         |                                               ^
         V    0                                          |    4
   +-----------+                                   +===========+
   |   enter   |-->----------------+-------------->|experiment |
   +-----------+                   |               +=====+=====+
                                   |                     |
                                   V    1                |
                             +-----------+               V
                             | proposed  |-------------->+
                        +--->+-----+-----+               |
                        |          |                     |
                        |          V    2                |
                        +<---+-----+-----+               V
                             | draft std |-------------->+
                        +--->+-----+-----+               |
                        |          |                     |
                        |          V    3                |
                        +<---+=====+=====+               V
                             | standard  |-------------->+
                             +=====+=====+               |
                                                         V    5
                                                   | historic  |

The transition from proposed standard (1) to draft standard (2) can only be by action of the IAB on the recommendation of the IESG and only after the protocol has been proposed standard (1) for at least four months.

The transition from draft standard (2) to standard (3) can only be by action of the IAB on the recommendation of the IESG and only after the protocol has been draft standard (2) for at least six months.

Occasionally, the decision may be that the protocol is not ready for standardization and will be assigned to the experimental state (4). This is off the standards track, and the protocol may be resubmitted to enter the standards track after further work. There are other paths into the experimental and historic states that do not involve IAB action.

Sometimes one protocol is replaced by another and thus becomes historic, or it may happen that a protocol on the standards track is in a sense overtaken by another protocol (or other events) and becomes historic (state 5).

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6. The Protocols

Subsection 6.1 lists recent RFCs and other changes. Subsections 6.2

   - 6.9 list the standards in groups by protocol state.

6.1. Recent Changes

6.1.1. New RFCs:

1252 - OSPF Version 2 MIB

A Proposed Standard protocol.

1251 - Who's Who in the Internet

This is an information document and does not specify any level of standard.

1250 - This memo.

1249 - DIXIE Protocol Specification

This is an information document and does not specify any level of standard.

1248 - OSPF Version 2 MIB

A Proposed Standard protocol.

1247 - OSPF Version 2

A Draft Standard protocol.

1246 - Experience with the OSPF Protocol

This is an information document and does not specify any level of standard.

1245 - OSPF Protocol Analysis

This is an information document and does not specify any level of standard.

1244 - Site Security Handbook

This is an information document and does not specify any level of standard.

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1243 - AppleTalk Management Information Base

A Proposed Standard protocol.

1242 - Benchmarking Terminology for Network Interconnection Devices

This is an information document and does not specify any level of standard.

1241 - A Scheme for an Internet Encapsulation Protocol: Version 1

This is a new Experimental protocol.

1240 - OSI Connectionless Transport Services
on top of UDP - Version: 1

A Proposed Standard protocol.

1239 - Reassignment of Experimental MIBs to Standard MIBs

A Proposed Standard protocol.

1238 - CLNS MIB - for use with Connectionless Network
Protocol (ISO 8473) and End System to Intermediate System (ISO 9542)

This is a new Experimental protocol.

1237 - Guidelines for OSI NSAP Allocation in the Internet

A Proposed Standard protocol.

1236 - IP to X.121 Address Mapping for DDN

This is an information document and does not specify any level of standard.

1235 - The Coherent File Distribution Protocol

This is a new Experimental protocol.

1234 - Tunneling IPX Traffic through IP Networks

A Proposed Standard protocol.

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1233 - Definitions of Managed Objects for the DS3 Interface Type

A Proposed Standard protocol.

1232 - Definitions of Managed Objects for the DS1 Interface Type

A Proposed Standard protocol.

1231 - IEEE 802.5 Token Ring MIB

A Proposed Standard protocol.

1230 - IEEE 802.4 Token Bus MIB

A Proposed Standard protocol.

1229 - Extensions to the Generic-Interface MIB

A Proposed Standard protocol.

1228 - SNMP-DPI - Simple Network Management Protocol Distributed Program Interface

This is a new Experimental protocol.

1227 - SNMP MUX Protocol and MIB

This is a new Experimental protocol.

1226 - Internet Protocol Encapsulation of AX.25 Frames

This is a new Experimental protocol.

1225 - Post Office Protocol - Version 3

A Draft Standard protocol.

1224 - Techniques for Managing Asynchronously Generated Alerts

This is a new Experimental protocol.

1223 - OSI CLNS and LLC1 Protocols on Network Systems HYPERchannel

This is an information document and does not specify any level of standard.

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1222 - Advancing the NSFNET Routing Architecture

This is an information document and does not specify any level of standard.

1221 - Host Access Protocol (HAP) Specification - Version 2

This is an information document and does not specify any level of standard.

1220 - Point-to-Point Protocol Extensions for Bridging

A Proposed Standard protocol.

1219 - On the Assignment of Subnet Numbers

This is an information document and does not specify any level of standard.

6.1.2. Other Changes:

The following are changes to protocols listed in the previous edition.

1213 - Management Information Base for Network Management of TCP/IP-based internets: MIB-II

Advanced to Standard protocol.

1212 - Concise MIB Definitions

Advanced to Draft Standard protocol.

Section 6.6 on Telnet Options has been added.

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6.2. Standard Protocols

Protocol Name Status RFC
======== ===================================== ============= =====
-------- Assigned Numbers Required 1060
-------- Gateway Requirements Required 1009
-------- Host Requirements - Communications Required 1122
-------- Host Requirements - Applications Required 1123
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
IGMP Internet Group Multicast Protocol Recommended 1112
UDP User Datagram Protocol Recommended 768
TCP Transmission Control Protocol Recommended 793
SMI Structure of Management Information Recommended 1155
MIB-I Management Information Base Recommended 1156
MIB-II Management Information Base-II Recommended 1213*
SNMP Simple Network Management Protocol Recommended 1157
DOMAIN 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
DNS-MX Mail Routing and the Domain System Recommended 974
CONTENT Content Type Header Field Recommended 1049
EGP Exterior Gateway Protocol Recommended 904
ECHO Echo Protocol Recommended 862
NTP Network Time Protocol Recommended 1119
NETBIOS NetBIOS Service Protocols Elective 1001,1002
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

Applicability Statements:

IGMP -- The Internet Activities Board intends to move towards general adoption of IP multicasting, as a more efficient solution than broadcasting for many applications. The host interface has been standardized in RFC-1112; however, multicast-routing gateways are in the experimental stage and are not widely available. An Internet host should support all of RFC-1112, except for the IGMP protocol itself which is optional; see RFC-1122 for more details. Even

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without IGMP, implementation of RFC-1112 will provide an important advance: IP-layer access to local network multicast addressing. It is expected that IGMP will become recommended for all hosts and gateways at some future date.

SMI, MIB-I, MIB-II SNMP -- The Internet Activities Board recommends that all IP and TCP implementations be network manageable. At the current time, this implies implementation of the Internet MIB-I (RFC-1156), the extensions in MIB-II (RFC-1213), and at least the recommended management protocol SNMP (RFC-1157).

6.3. Network-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 Hyperchannel Elective 1044
IP-ARC Internet Protocol on ARCNET Elective 1051
IP-SLIP Transmission of IP over Serial Lines Elective 1055
IP-NETBIOS Transmission of IP over NETBIOS Elective 1088
IP-FDDI Transmission of IP over FDDI Elective 1188
IP-IPX Transmission of 802.2 over IPX Networks Elective 1132

Applicability Statements:

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. See also the Host and Gateway Requirements RFCs for more specific information on network-specific ("link layer") protocols.

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6.4. Draft Standard Protocols

Protocol Name Status RFC
======== ===================================== ============== =====
OSPF2 Open Shortest Path First Routing V2 Elective 1247*
POP3 Post Office Protocol, Version 3 Elective 1225*
Concise-MIB Concise MIB Definitions Elective 1212*
FINGER Finger Protocol Elective 1196
IP-FDDI Internet Protocol on FDDI Networks Elective 1188
TOPT-LINE Telnet Linemode Option Elective 1184
PPP Point to Point Protocol Elective 1171
-------- Mail Privacy: Procedures Elective 1113
-------- Mail Privacy: Key Management Elective 1114
-------- Mail Privacy: Algorithms Elective 1115
BOOTP Bootstrap Protocol Recommended 951,1084
RIP Routing Information Protocol Elective 1058
TP-TCP ISO Transport Service on top of the TCP Elective 1006
NICNAME WhoIs Protocol Elective 954
TFTP Trivial File Transfer Protocol Elective 783

Applicability Statements:

RIP -- The Routing Information Protocol (RIP) is widely implemented and used in the Internet. However, both implementors and users should be aware that RIP has some serious technical limitations as a routing protocol. The IETF is currently developing several candidates for a new standard "open" routing protocol with better properties than RIP. The IAB urges the Internet community to track these developments, and to implement the new protocol when it is standardized; improved Internet service will result for many users.

TP-TCP -- As OSI protocols become more widely implemented and used, there will be an increasing need to support interoperation with the TCP/IP protocols. The Internet Engineering Task Force is formulating strategies for interoperation. RFC-1006 provides one interoperation mode, in which TCP/IP is used to emulate TP0 in order to support OSI applications. Hosts that wish to run OSI connection-oriented applications in this mode should use the procedure described in RFC- 1006. In the future, the IAB expects that a major portion of the Internet will support both TCP/IP and OSI (inter-)network protocols in parallel, and it will then be possible to run OSI applications across the Internet using full OSI protocol "stacks".

PPP -- Point to Point Protocol is a method of sending IP over serial lines, which are a type of physical network. It is anticipated that PPP will be advanced to the network-specific standard protocol state in the future.

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6.5. Proposed Standard Protocols

Protocol Name Status RFC
======== ===================================== ============== =====
OSPF-MIB OSPF Version 2 MIB Elective 1248,1252*
AT-MIB Appletalk MIB Elective 1243*
OSI-UDP OSI TS on UDP Elective 1240*
STD-MIBs Reassignment of Exp MIBs to Std MIBs Elective 1239*
OSI-NSAP Guidelines for OSI NSAP Allocation Elective 1237*
IPX-IP Tunneling IPX Traffic through IP Nets Elective 1234*
DS3-MIB DS3 Interface Objects Elective 1233*
DS1-MIB DS1 Interface Objects Elective 1232*
802.5-MIB IEEE 802.5 Token Ring MIB Elective 1231*
802.4-MIP IEEE 802.4 Token Bus MIB Elective 1230*
GINT-MIB Extensions to the Generic-Interface MIB Elective 1229*
PPP-EXT PPP Extensions for Bridging Elective 1220*
OIM-MIB-II OSI Internet Management: MIB-II Elective 1214
IP-SMDS IP Datagrams over the SMDS Service Elective 1209
IP-ARCNET Transmitting IP Traffic over ARCNET Nets Elective 1201
IS-IS OSI IS-IS for TCP/IP Dual Environments Elective 1195
IP-MTU Path MTU Discovery Elective 1191
CMOT Common Management Information Services Elective 1189
and Protocol over TCP/IP
PPP-INIT PPP Initial Configuration Options Elective 1172
BGP Border Gateway Protocol Elective 1163,1164
IP-CMPRS Compressing TCP/IP Headers Elective 1144
ISO-TS-ECHO Echo for ISO-8473 Elective 1139
SUN-NFS Network File System Protocol Elective 1094
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(84) and RFC-822 Elective 987,1026
NNTP Network News Transfer Protocol Elective 977
HOSTNAME HOSTNAME Protocol Elective 953
SFTP Simple File Transfer Protocol Elective 913
RLP Resource Location Protocol Elective 887
SUPDUP SUPDUP Protocol Elective 734

Applicability Statements:

IP-SMDS and IP-ARCNET -- These define methods of sending IP over particular network types. It is anticipated that these will be advanced to the network specific standard protocol state in the future.

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6.6. Telnet Options

For convenience all the Telnet Options are collected here with both
their state and status.

Protocol Name Number State Status RFC
======== ===================================== ============== =====
TOPT-BIN Binary Transmission 0 Std Rec 856*
TOPT-ECHO Echo 1 Std Rec 857*
TOPT-RECN Reconnection 2 Prop Ele ...*
TOPT-SUPP Suppress Go Ahead 3 Std Rec 858*
TOPT-APRX Approx Message Size Negotiation 4 Prop Ele ...*
TOPT-STAT Status 5 Std Rec 859*
TOPT-TIM Timing Mark 6 Std Rec 860*
TOPT-REM Remote Controlled Trans and Echo 7 Prop Ele 726*
TOPT-OLW Output Line Width 8 Prop Ele ...*
TOPT-OPS Output Page Size 9 Prop Ele ...*
TOPT-OCRD Output Carriage-Return Disposition 10 Prop Ele 652*
TOPT-OHT Output Horizontal Tabstops 11 Prop Ele 653*
TOPT-OHTD Output Horizontal Tab Disposition 12 Prop Ele 654*
TOPT-OFD Output Formfeed Disposition 13 Prop Ele 655*
TOPT-OVT Output Vertical Tabstops 14 Prop Ele 656*
TOPT-OVTD Output Vertical Tab Disposition 15 Prop Ele 657*
TOPT-OLD Output Linefeed Disposition 16 Prop Ele 658*
TOPT-EXT Extended ASCII 17 Prop Ele 698*
TOPT-LOGO Logout 18 Prop Ele 727*
TOPT-BYTE Byte Macro 19 Prop Ele 735*
TOPT-DATA Data Entry Terminal 20 Prop Ele 1043*
TOPT-SUP SUPDUP 21 Prop Ele 734*
TOPT-SUPO SUPDUP Output 22 Prop Ele 749*
TOPT-SNDL Send Location 23 Prop Ele 779*
TOPT-TERM Terminal Type 24 Prop Ele 930*
TOPT-EOR End of Record 25 Prop Ele 885*
TOPT-TACACS TACACS User Identification 26 Prop Ele 927*
TOPT-OM Output Marking 27 Prop Ele 933*
TOPT-TLN Terminal Location Number 28 Prop Ele 946*
TOPT-3270 Telnet 3270 Regime 29 Prop Ele 1041*
TOPT-X.3 X.3 PAD 30 Prop Ele 1053*
TOPT-NAWS Negotiate About Window Size 31 Prop Ele 1073*
TOPT-TS Terminal Speed 32 Prop Ele 1079*
TOPT-RFC Remote Flow Control 33 Prop Ele 1080*
TOPT-LINE Linemode 34 Draft Ele 1184*
TOPT-XDL X Display Location 35 Prop Ele 1096*
TOPT-EXTOP Extended-Options-List 255 Std Rec 861*

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6.7. Experimental Protocols

Protocol Name Status RFC
======== ===================================== ============== =====
IN-ENCAP Internet Encapsulation Protocol Limited Use 1241*
CLNS-MIB CLNS-MIB Limited Use 1238*
CFDP Coherent File Distribution Protocol Limited Use 1235*
SNMP-DPI SNMP Distributed Program Interface Limited Use 1228*
SNMP-MUX SNMP MUX Protocol and MIB Limited Use 1227*
IP-AX25 IP Encapsulation of AX.25 Frames Limited Use 1226*
ALERTS Managing Asynchronously Generated Alerts Limited Use 1224*
MPP Message Posting Protocol Limited Use 1204
ST-II Stream Protocol Limited Use 1190
SNMP-BULK Bulk Table Retrieval with the SNMP Limited Use 1187
DNS-RR New DNS RR Definitions Limited Use 1183
NTP-OSI NTP over OSI Remote Operations Limited Use 1165
MSP Message Send Protocol Limited Use 1159
EHF-MAIL Encoding Header Field for Mail Elective 1154
DMF-MAIL Digest Message Format for Mail Elective 1153
RDP Reliable Data Protocol Limited Use 908,1151
-------- Mapping between X.400(88) and RFC-822 Elective 1148
TCP-ACO TCP Alternate Checksum Option Not Recommended 1146
-------- Mapping full 822 to Restricted 822 Elective 1137
IP-DVMRP IP Distance Vector Multicast Routing Not Recommended 1075
TCP-LDP TCP Extensions for Long Delay Paths Limited Use 1072
IMAP2 Interactive Mail Access Protocol Limited Use 1176,1064
IMAP3 Interactive Mail Access Protocol Limited Use 1203
VMTP Versatile Message Transaction Protocol Elective 1045
COOKIE-JAR Authentication Scheme Not Recommended 1004
NETBLT Bulk Data Transfer Protocol Not Recommended 998
IRTP Internet Reliable Transaction Protocol Not Recommended 938
AUTH Authentication Service Not Recommended 931
LDP Loader Debugger Protocol Not Recommended 909
NVP-II Network Voice Protocol Limited Use ISI-memo
PVP Packet Video Protocol Limited Use ISI-memo

6.8. Informational Protocols

Protocol Name Status RFC
======= ==================================== =============== =====
DIXIE DIXIE Protocol Specification Limited Use 1249*
IP-X.121 IP to X.121 Address Mapping for DDN Limited Use 1236*
OSI-HYPER OSI and LLC1 on HYPERchannel Limited Use 1223*
HAP2 Host Access Protocol Limited Use 1221*
SUBNETASGN On the Assignment of Subnet Numbers Limited Use 1219*
SNMP-TRAPS Defining Traps for use with SNMP Limited Use 1215
DAS Directory Assistance Service Limited Use 1202

Page 24

MD4 MD4 Message Digest Algorithm Limited Use 1186
LPDP Line Printer Daemon Protocol Limited Use 1179

6.9. Historic Protocols

Protocol Name Status RFC
======= ===================================== ============== =====
SGMP Simple Gateway Monitoring Protocol Not Recommended 1028
HEMS High Level Entity Management Protocol Not Recommended 1021
STATSRV Statistics Server Not Recommended 996
POP2 Post Office Protocol, Version 2 Not Recommended 937
RATP Reliable Asynchronous Transfer Protocol Not Recommended 916
HFEP Host - Front End Protocol Not Recommended 929*
THINWIRE Thinwire Protocol Not Recommended 914
HMP Host Monitoring Protocol Not Recommended 869
GGP Gateway Gateway Protocol Not Recommended 823
RTELNET Remote Telnet Service Not Recommended 818
CLOCK DCNET Time Server Protocol Not Recommended 778
MPM Internet Message Protocol Not Recommended 759
NETRJS Remote Job Service Not Recommended 740
NETED Network Standard Text Editor Not Recommended 569
RJE Remote Job Entry Not Recommended 407
XNET Cross Net Debugger Not Recommended 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. IAB, IETF, and IRTF Contacts

7.1.1. Internet Activities Board (IAB) Contact

Please send your comments about this list of protocols and especially about the Draft Standard Protocols to the Internet Activities Board care of Bob Braden, IAB Executive Director.


Bob Braden
Executive Director of the IAB
USC/Information Sciences Institute
4676 Admiralty Way
Marina del Rey, CA 90292-6695



Page 25

Vinton G. Cerf
Chair of the IAB
Corporation for National Research Initiatives
1895 Preston White Drive, Suite 100
Reston, VA 22091



7.1.2. Internet Engineering Task Force (IETF) Contact


Phill Gross
Chair of the IETF
Advanced Network and Services
100 Clearbrook Road
Elmsford, NY 10523



Greg Vaudreuil
IESG Secretary
Corporation for National Research Initiatives
1895 Preston White Drive, Suite 100
Reston, VA 22091



7.1.3. Internet Research Task Force (IRTF) Contact


David D. Clark
Chair of the IRTF
Massachusetts Institute of Technology
Laboratory for Computer Science
545 Main Street
Cambridge, MA 02139



Page 26

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-1060) 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-1122 and RFC-1123) 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".

Page 27

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 Distribution Contact


DDN Network Information Center
SRI International
Room EJ291
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 NISC.SRI.COM, 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 MAIL-SERVER@NISC.SRI.COM and

Page 28

in the body of the message indicate the file name, as in "send rfc:rfcnnnn.txt".

Some RFCs are now available in PostScript, these may be obtained from the NIC in a similar fashion by substituting ".ps" for ".txt".

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 NIC.DDN.MIL computer following the same procedures used to obtain RFCs.

7.5. Other Sources for Requests for Comments

Information about other sources for RFCs and the procedures for copying RFCs form those sources may be found in the file "in- notes/rfc-retrieval.txt" on the host VENERA.ISI.EDU.

8. Security Considerations

Security issues are not addressed in this memo.

9. Author's Address

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

Phone: 213-822-1511

   Fax:   213-823-6714

Email: Postel@ISI.EDU