Network Working Group Internet Architecture Board Request for Comments: 1600 J. Postel, Editor Obsoletes: RFCs 1540, 1500, 1410, 1360, March 1994 1280, 1250, 1100, 1083, 1130, 1140, 1200 STD: 1 Category: Standards Track INTERNET 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 Architecture Board (IAB). This memo is an Internet Standard. Distribution of this memo is unlimited. Table of Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. The Standardization Process . . . . . . . . . . . . . . . . 3 2. The Request for Comments Documents . . . . . . . . . . . . . 5 3. Other Reference Documents . . . . . . . . . . . . . . . . . 6 3.1. Assigned Numbers . . . . . . . . . . . . . . . . . . . . . 6 3.2. Gateway Requirements . . . . . . . . . . . . . . . . . . . 6 3.3. Host Requirements . . . . . . . . . . . . . . . . . . . . 6 3.4. The MIL-STD Documents . . . . . . . . . . . . . . . . . . 6 4. Explanation of Terms . . . . . . . . . . . . . . . . . . . . 7 4.1. Definitions of Protocol State (Maturity Level) . . . . . . 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 (Requirement Level) . . . 9 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 Internet Architecture Board [Page 1] RFC 1600 Internet Standards March 1994 6.1.2. Other Changes . . . . . . . . . . . . . . . . . . . . 19 6.2. Standard Protocols . . . . . . . . . . . . . . . . . . . 20 6.3. Network-Specific Standard Protocols . . . . . . . . . . 22 6.4. Draft Standard Protocols . . . . . . . . . . . . . . . . 23 6.5. Proposed Standard Protocols . . . . . . . . . . . . . . 24 6.6. Telnet Options . . . . . . . . . . . . . . . . . . . . . 27 6.7. Experimental Protocols . . . . . . . . . . . . . . . . . 28 6.8. Informational Protocols . . . . . . . . . . . . . . . . 29 6.9. Historic Protocols . . . . . . . . . . . . . . . . . . . 30 6.10 Obsolete Protocols . . . . . . . . . . . . . . . . . . . 31 7. Contacts . . . . . . . . . . . . . . . . . . . . . . . . . 32 7.1. IAB, IETF, and IRTF Contacts . . . . . . . . . . . . . . 32 7.1.1. Internet Architecture Board (IAB) Contact . . . . . . 32 7.1.2. Internet Engineering Task Force (IETF) Contact . . . . 32 7.1.3. Internet Research Task Force (IRTF) Contact . . . . . 33 7.2. Internet Assigned Numbers Authority (IANA) Contact . . . 34 7.3. Request for Comments Editor Contact . . . . . . . . . . 35 7.4. Network Information Center Contact . . . . . . . . . . . 35 7.5. Sources for Requests for Comments . . . . . . . . . . . 36 8. Security Considerations . . . . . . . . . . . . . . . . . 36 9. Author's Address . . . . . . . . . . . . . . . . . . . . . 36 Introduction A discussion of the standardization process and the RFC document series is presented first, followed by an explanation of the terms. Sections 6.2 - 6.10 contain the lists of protocols in each stage of standardization. Finally are pointers to references and contacts for further information. This memo is intended to be issued approximately quarterly; please be sure the copy you are reading is current. Current copies may be obtained from the Network Information Center (INTERNIC) or from the Internet Assigned Numbers Authority (IANA) (see the contact information at the end of this memo). Do not use this edition after 31-May-94. See Section 6.1 for a description of recent changes. In the official lists in sections 6.2 - 6.10, an asterisk (*) next to a protocol denotes that it is new to this document or has been moved from one protocol level to another, or differs from the previous edition of this document. Internet Architecture Board [Page 2] RFC 1600 Internet Standards March 1994 1. The Standardization Process The Internet Architecture Board maintains this list of documents that define standards for the Internet protocol suite. See RFC-1358 for the charter of the IAB and 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). Each of these groups has a steering group called the IESG and IRSG, respectively. The IETF develops 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. The definitive description of the Internet standards process is found in RFC-1310. The majority of Internet protocol development and standardization activity takes place in the working groups of the IETF. Protocols which are to become standards in the Internet go through a series of states or maturity levels (proposed standard, draft standard, and standard) involving increasing amounts of scrutiny and testing. When a protocol completes this process it is assigned a STD number (see RFC-1311). At each step, the Internet Engineering Steering Group (IESG) of the IETF must make a recommendation for advancement of the protocol. To allow time for the Internet community to consider and react to standardization proposals, a minimum delay of 6 months before a proposed standard can be advanced to a draft standard and 4 months before a draft standard can be promoted to standard. It is general 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 a special review committee may be appointed consisting of experts from the IETF, IRTF and the IAB with the purpose of recommending an explicit action. 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. Internet Architecture Board [Page 3] RFC 1600 Internet Standards March 1994 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 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. 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 the documentation of such experimental work in the RFC series is encouraged, 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. A few protocols have achieved widespread implementation without the approval of the IESG. For example, some vendor protocols have become very important to the Internet community even though they have not been recommended by the IESG. However, the IAB strongly recommends that the standards process be used in the evolution of the protocol suite to maximize interoperability (and to prevent incompatible protocol requirements from arising). The use of the terms "standard", "draft standard", and "proposed standard" are reserved in any RFC or other publication of Internet protocols to only those protocols which the IESG 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. Few protocols are required to be implemented in all systems; this is because there is such a variety of possible systems, for example, Internet Architecture Board [Page 4] RFC 1600 Internet Standards March 1994 gateways, routers, 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 may be 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, and see RFC 1543). 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 the IESG. 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 "Internet Official Protocol Standards" Internet Architecture Board [Page 5] RFC 1600 Internet Standards March 1994 memo is the reference for determining the correct RFC for the current specification of each protocol. The RFCs are available from the INTERNIC, and a number of other sites. For more information about obtaining RFCs, see Sections 7.4 and 7.5. 3. Other Reference Documents There are three other reference documents of interest in checking the current status of protocol specifications and standardization. These are the Assigned Numbers, 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 3.4. 3.1. Assigned Numbers The "Assigned Numbers" 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-1340. 3.2. 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. 3.3. 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. 3.4. 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 DISA and to the IESG. 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 Internet Architecture Board [Page 6] RFC 1600 Internet Standards March 1994 of documents be used together, along with RFC-1122 and RFC-1123. The Internet 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