Keith W. Uncapher


Keith W. Uncapher
Denver, CO, USA
Associated organizations
Fields of study


Keith Uncapher was a computer scientist whose research at RAND and the Information Sciences Institute at the University of Southern California was fundamental to the development of ARPANET and what would become the Internet.

Uncapher was born in Denver in 1922 and moved to California as an infant with his father, a supervisor at Pacific Telephone, and his mother, a homemaker. He served in the Navy for five years during World War II. He was a petty officer in aviation maintenance and radar systems. After the war, he attended Glendale College and earned a B.S. in electrical engineering from California Polytechnic University in 1950.

Following graduation, Uncapher joined RAND, which was a center for defense research during the Cold War. He worked at RAND for twenty-two years and became director of its computer science division. In the 1950s, he became a specialist in operating RAND’s JOHNNIAC computer (named for computing pioneer John von Neumann), developing its use for mathematical applications. He and his colleagues advertised what they called the JOSS (JOHNNIAC Open Shop System) to mathematicians, convincing them that they could use this teletype interface to unpack difficult problems without needing to understand programming.

As Uncapher said in a 1989 interview, “The first reaction, and a common reaction I ran across, was, ‘I can now solve my missile problem in 20 minutes; it used to take me four hours.’ A second step generally was, ‘I am reformulating what I want to do, because I can now add a lot more complexity.’ And the third was a total surprise to me: namely, they found it easy enough to turn over to their secretaries the solving of their run-of-the-mill problems, which they didn't have to fuss with at all. And the fourth was the best of all. In any kind of computer based user aid, and what was related to me is what they liked about it, and this was after months of operation with it on the part of many of the mathematicians, they were now able to dig into their bottom drawer and pull out problems that they claimed they couldn't solve. What I think they were really saying is, ‘We are now able to solve them,’ because it wasn't too hard. They were always able to, but it wasn't worth the effort.”

Known as a skilled engineer and developer of human capital, he oversaw the development of a project for the Air Force that laid the theoretical groundwork for transmitting data on ARPANET. In the early 1960s, the Air Force feared that AT&T’s major microwave towers would be a target for enemy bombing. It asked RAND to create a national network that could survive if parts of the system were severed. Uncapher gathered a team of about a dozen scientists, and put digital communications expert Paul Baran in the lead of developing a durable architecture for the network.

Baran initially developed what Uncapher called a “flakey architecture”: a national network of AM radio stations tied together by emergency boxes that disk jockeys would plug-in during an emergency. Uncapher rejected this idea, and decided to push forward on a design that would be digital, transistor-based, and not run through telephone lines. Uncapher was concerned that existing phone lines lacked the capacity and quality to carry digital signals.

Baran’s solution was the “hot potato” algorithm: that digital signals should be sent in packets as quickly as possible to avoid using too much storage or power at any node. Uncapher described this as “the first document to put forth the notion of an equivalent of an electronic envelope, a packet, with information inside the envelope, and addresses on the outside, along with parity detection capability, and then a mechanism for error avoidance.” In the end, the Air Force declined to invest in this system, but the architecture and concept of packet switching became a fundamental part of the ARPANET, launched by computer scientists at the University of California, Los Angeles, in 1969.

In 1972, Uncampher broke with RAND and established the Information Sciences Institute at the University of Southern California. ISI was a non-profit research laboratory that developed computer applications, particularly for the Department of Defense. One ISI project created the Internet’s system of domain names, including the suffixes .com, .net, and .edu. Another project, called Mosis, developed more economical ways to create prototype silicon chips.

In 1987, he left ISI to co-found the Corporation for National Research Initiatives, a non-profit focused on information infrastructure research.

He was elected to the National Academy of Engineering in 1998.

Further Reading

Katie Hafner, "Keith Uncapher, 80, Networking Pioneer, Dies," NY Times, 16 Oct. 2002.

Arthur L. Norberg,Interview with Keith Uncapher, July 1989. Charles Babbage Institute, University of Minnesota, Minneapolis.