TCP/IP 25th Anniversary

By: Brian Carpenter, IETF Chair

Date: November 7, 2006

line break image

The foundation of the Internet is composed of the basic Internet Protocol (IP) and the generally used Transmission Control Protocol (TCP), which together are known as TCP/IP.

TCP/IP was formally standardised in September 1981 – 25 years ago – by the publication of RFC 791 and RFC 793.

The editor of those documents was the late Jon Postel, then of the Information Sciences Institute (ISI) at the University of Southern California. Postel indicated on the original documents that they were prepared for

Defense Advanced Research Projects Agency
Information Processing Techniques Office
1400 Wilson Boulevard
Arlington, Virginia 22209


Information Sciences Institute
University of Southern California
4676 Admiralty Way
Marina del Rey, California 90291

While Vint Cerf and Robert Kahn were widely credited with the design of TCP/IP, many others involved in the ARPANET project made significant contributions.

According to Vint Cerf, “The core of the documents was RFC 675 from December 1974 authored by Carl Sunshine, Yogen Dalal and me. The subsequent sequence of documents leading up to RFC 791 and 793 had the benefit of quite a few hands, including the participation of Dave Clark, Jon Postel, Bob Braden, Ray Tomlinson, Bill Plummer, Jim Mathis, as well as other early implementers of TCP.” Of course, at the time, many other unnamed contributors who participated in the debate.


Original 1982 IP Transition

Photo: Daniel Karrenberg

Since the RFC series was launched in 1969 by Steve Crocker at UCLA, it has continued as the public archive of the Internet’s fundamental technology. Since 1977 it has been hosted by the Information Sciences Institute of USC. ARPA funding ended in 1998, at which time ISOC took over, as its first major funding effort for Internet standards. Since the end of 2005, the RFC Editor has been supported by the IETF Administrative Support Activity, which is hosted and partly funded by the Internet Society.


The long-serving RFC Editor, Jon Postel, passed away in 1998. His close colleague throughout all these years Joyce Reynolds said: “Operating systems and computers have changed over the years, but Jon’s perseverance about the consistency of the RFC style and quality of the documents remained true.” Many friends and colleagues remember him at

“We can’t yet say that the Internet is mature, “says Brian Carpenter, chair of the IETF, “but it’s a great tribute to the pioneers that the two most basic specifications that were published a quarter of a century ago are still largely valid today. I hope the IP version 6 standard will do as well.”

birth of the internet

Stanford Plaque commemorating
early work done on TCP/IP
in 1973-1975

Courtesy of Vint Cerf