There are a wide range of official Internet protocol standards. A list of official standards is documented in the Request For Comments documents, with a recent version at RFC 3300, and an up-to-date list maintained at RFC-Editor.org. The first RFC explicitly declared an official standard was RFC 733. The official protocol standards are listed in the following categories:
- Standard. Established as a standard protocol by the IESG.
- Draft. On track, likely a future standard protocol.
- Proposed. Early stage, proposed protocol.
- Historic. Older protocols, usually superseded or unused.
- Experimental. Research protocols, documented to provide a convenient reference for researchers.
- Informational. Protocols developed by other organizations, such as official standards organizations and commercial network companies, were sometimes published as RFC’s to provide a standard reference. The last list of information protocols can be found in RFC 2500.
Each protocol is assigned a status of “Required”, “Recommended”, “Elective”, “Limited Use”, or “Not Recommended”, in descending order of priority. Only a very few essential protocols are labeled “Required”.
Working groups of the IETF do most of the work on standardization of Internet protocols as they go through proposed standard, draft standard, and actual standard phases. A protocol published as a proposed standard is usually intended to become an actual standard, but is not promoted to draft standard for at least six months to allow time for the Internet community to review and comment. A draft standard is not promoted to full standard for at least four months, after operational experience has been obtained, and when there is demonstrated interoperability between two or more independent implementations.
A full standard must be instantiated by at least two independent, fully working implementations of the defined protocol. When a protocol becomes a full standard it is given an STD number as described in RFC 1311.