Request for Comments

The inception of the RFC format occurred in 1969 as part of the seminal ARPANET project.[4] Today, it is the official publication channel for the Internet Engineering Task Force (IETF), the Internet Architecture Board (IAB), 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.[6][7] 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. RFC 1, titled "Host Software", was written by Steve Crocker of the University of California, Los Angeles (UCLA), and published on April 7, 1969.[8] Although written by Steve Crocker, the RFC had emerged from an early working group discussion between Steve Crocker, Steve Carr, and Jeff Rulifson.

In RFC 3, 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 (IMPs) on ARPANET. The Augmentation Research Center (ARC) 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 (InterNIC), which was managed by Elizabeth J. Feinler to distribute the RFCs along with other network information.[9] From 1969 until 1998, Jon Postel served as the RFC editor. On his death in 1998, his obituary was published as RFC 2468.

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 (USC) Information Sciences Institute (ISI) 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.[10] 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 (IRTF), and an independent stream from other outside sources.[11] A new model was proposed in 2008, refined, and published in August 2009, splitting the task into several roles,[12] including the RFC Series Advisory Group (RSAG). The model was updated in 2012.[13] The streams were also refined in December 2009, with standards defined for their style.[14] In January 2010 the RFC editor function was moved to a contractor, Association Management Solutions, with Glenn Kowack serving as interim series editor.[15] In late 2011, Heather Flanagan was hired as the permanent RFC Series Editor. Also at that time, an RFC Series Oversight Committee (RSOC) was created.[16]

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.[17]

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 RFC 2026 (The Internet Standards Process, Revision 3).[18]

The RFC production process differs from the standardization process of formal standards organizations such as International Organization for Standardization (ISO). 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" (as defined by RFC 2119 and RFC 8174), augmented Backus–Naur form (ABNF) (RFC 5234) as a meta-language, and simple text-based formatting, in order to keep the RFCs consistent and easy to understand.[18]

RFC 2046                      Media Types                  November 1996


   A. Collected Grammar ....................................   43

1.  Introduction

   The first document in this set, RFC 2045, defines a number of header
   fields, including Content-Type. The Content-Type field is used to
   specify the nature of the data in the body of a MIME entity, by
   giving media type and subtype identifiers, and by providing auxiliary
   information that may be required for certain media types.  After the

The official source for RFCs on the World Wide Web is the RFC Editor. Almost any published RFC can be retrieved via a URL of the form http://www.rfc-editor.org/rfc/rfc5000.txt, shown for RFC 5000.

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(s), 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 (ISSN) of the RFC series is 2070–1721.[14]

Not all RFCs are standards.[20][21] Each RFC is assigned a designation with regard to status within the Internet standardization process. This status is one of the following: Informational, Experimental, Best Current Practice, Standards Track, or Historic.

Each RFC is static; if the document is changed, it is submitted again and assigned a new RFC number.

• April Fools' Day RFC
• Best Current Practice
• Internet Experiment Note
• List of RFCs

• RFC Editor
• RFC Database
• RFC Errata
• RFC Frequently Asked Questions
• RFC Index (text)
• Official Internet Protocol Standards
• IETF's RFC page
• RFC Index (HTML) With the text of each RFC, also mentions what other RFCs this one "updates" or is "updated by".