Request for Comments

A Request for Comments is a publication in a series from the principal technical development and standards-setting bodies for the Internet, most prominently the Internet Engineering Task Force. An RFC is authored by individuals or groups of engineers and computer scientists in the form of a memorandum describing methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems. It is submitted either for peer review or to convey new concepts, information, or, occasionally, engineering humor.
The IETF adopts some of the proposals published as RFCs as Internet Standards. However, many RFCs are informational or experimental in nature and are not standards. The RFC system was invented by Steve Crocker in 1969 to help record unofficial notes on the development of ARPANET. RFCs have since become official documents of Internet specifications, communications protocols, procedures, and events. According to Crocker, the documents "shape the Internet's inner workings and have played a significant role in its success," but are not widely known outside the community.
Outside of the Internet community, other documents also called requests for comments have been published, as in U.S. Federal government work, such as the National Highway Traffic Safety Administration.

History

The inception of the RFC format occurred in 1969 as part of the seminal ARPANET project. Today, it is the official publication channel for the Internet Engineering Task Force, the Internet Architecture Board, and to some extent the global community of computer network researchers in general.
The authors of the first RFCs typewrote their work and circulated hard copies among the ARPA researchers. Unlike the modern RFCs, many of the early RFCs were actual Requests for Comments and were titled as such to avoid sounding too declarative and to encourage discussion. The RFC leaves questions open and is written in a less formal style. This less formal style is now typical of Internet Draft documents, the precursor step before being approved as an RFC.
In December 1969, researchers began distributing new RFCs via the newly operational ARPANET., titled "Host Software", was written by Steve Crocker of the University of California, Los Angeles, and published on April 7, 1969. Although written by Steve Crocker, the RFC had emerged from an early working group discussion between Steve Crocker, Steve Carr, and Jeff Rulifson.
In, which first defined the RFC series, Crocker started attributing the RFC series to the Network Working Group. Rather than being a formal committee, it was a loose association of researchers interested in the ARPANET project. In effect, it included anyone who wanted to join the meetings and discussions about the project.
Many of the subsequent RFCs of the 1970s also came from UCLA, because UCLA is one of the first of what were Interface Message Processors on ARPANET. The Augmentation Research Center at Stanford Research Institute, directed by Douglas Engelbart, is another of the four first of what were ARPANET nodes and the source of early RFCs. The ARC became the first network information center, which was managed by Elizabeth J. Feinler to distribute the RFCs along with other network information.
On April Fools' Day 1978, was published as a parody of the TCP/IP documentation style. This resumed in 1989 with the publication of, which describes an option for telnet clients to display subliminal messages. Subsequent April Fools' Day RFCs have been published annually since then, notably which describes the Hyper Text Coffee Pot Control Protocol and defines the HTTP 418 "I'm a teapot" status. Humorous RFCs date back to, published in January 1973.

RFC Editor function

From 1969 until 1998, Jon Postel served as the RFC editor. On his death in 1998, his obituary was published as.
Following the expiration of the original ARPANET contract with the U.S. federal government, the Internet Society, acting on behalf of the IETF, contracted with the Networking Division of the University of Southern California Information Sciences Institute to assume the editorship and publishing responsibilities under the direction of the IAB.
Sandy Ginoza joined USC/ISI in 1999 to work on RFC editing, and Alice Hagens in 2005. Bob Braden took over the role of RFC project lead, while Joyce K. Reynolds continued to be part of the team until October 13, 2006.
In July 2007, streams of RFCs were defined, so that the editing duties could be divided. IETF documents came from IETF working groups or submissions sponsored by an IETF area director from the Internet Engineering Steering Group. The IAB can publish its own documents. A research stream of documents comes from the Internet Research Task Force, and an independent stream from other outside sources. A new model was proposed in 2008, refined, and published in August 2009, splitting the task into several roles, including the RFC Series Advisory Group. The model was updated in 2012,, and 2020.
The streams were also refined in December 2009, with standards defined for their style.
In January 2010, the RFC Editor function was moved to a contractor, Association Management Solutions, with Glenn Kowack serving as interim series editor. In late 2011, Heather Flanagan was hired as the permanent RFC Series Editor. Also at that time, an RFC Series Oversight Committee was created.
In 2020, the IAB convened the RFC Editor Future Development program to discuss potential changes to the RFC Editor model. The results of the program were included the RFC Editor Model as defined in, published in June 2022. Generally, the new model is intended to clarify responsibilities and processes for defining and implementing policies related to the RFC series and the RFC Editor function. Changes in the new model included establishing the position of the RFC Consulting Editor, the RFC Series Working Group, and the RFC Series Approval Board. It also established a new Editorial Stream for the RFC Series and concluded the RSOC. The role of the RSE was changed to the RFC Series Consulting Editor. In September 2022, Alexis Rossi was appointed to that position.

New publishing format

Requests for Comments were originally produced in non-reflowable text format. In August 2019, the format was changed so that new documents can be viewed optimally in devices with varying display sizes.

Production and versioning

The RFC Editor assigns each RFC a serial number. Once assigned a number and published, an RFC is never rescinded or modified; if the document requires amendments, the authors publish a revised document. Therefore, some RFCs supersede others; the superseded RFCs are said to be deprecated, obsolete, or obsoleted by the superseding RFC. Together, the serialized RFCs compose a continuous historical record of the evolution of Internet standards and practices. The RFC process is documented in .
The RFC production process differs from the standardization process of formal standards organizations such as International Organization for Standardization. Internet technology experts may submit an Internet Draft without support from an external institution. Standards-track RFCs are published with approval from the IETF, and are usually produced by experts participating in IETF Working Groups, which first publish an Internet Draft. This approach facilitates initial rounds of peer review before documents mature into RFCs.
The RFC tradition of pragmatic, experience-driven, after-the-fact standards authorship accomplished by individuals or small working groups can have important advantages over the more formal, committee-driven process typical of ISO and national standards bodies.
Most RFCs use a common set of terms such as "MUST" and "NOT RECOMMENDED", augmented Backus–Naur form as a meta-language, and simple text-based formatting, in order to keep the RFCs consistent and easy to understand.

Sub-series

The RFC series contains three sub-series for IETF RFCs: BCP, FYI, and STD. Best Current Practice is a sub-series of mandatory IETF RFCs not on standards track. For Your Information is a sub-series of informational RFCs promoted by the IETF as specified in . In 2011, obsoleted FYI 1 and concluded this sub-series. Standard used to be the third and highest maturity level of the IETF standards track specified in . In 2011 reduced the standards track to two maturity levels.

Streams

There are five streams of RFCs: IETF, IRTF, IAB, independent submission, and Editorial. Only the IETF creates BCPs and RFCs on the standards track. The IAB publishes informational documents relating to policy or architecture. The IRTF publishes the results of research, either as informational documents or as experiments. Independent submissions are published
at the discretion of the Independent Submissions Editor. Non-IETF documents are reviewed by the IESG for conflicts with IETF work. IRTF and independent RFCs generally contain relevant information or experiments for the Internet at large not in conflict with IETF work. compare. The Editorial Stream is used to effect editorial policy changes across the RFC series.

Obtaining RFCs

The official source for RFCs on the World Wide Web is the RFC Datatracker. Almost any published RFC can be retrieved via a URL of the form https://datatracker.ietf.org/doc/html/rfc5000, shown for.
Every RFC is submitted as plain ASCII text and is published in that form, but may also be available in other formats.
For easy access to the metadata of an RFC, including abstract, keywords, author, publication date, errata, status, and especially later updates, the RFC Editor site offers a search form with many features. A redirection sets some efficient parameters, example: rfc:5000.
The official International Standard Serial Number of the RFC series is 2070-1721.