From Grodno to a Philadelphia grocery
Paul Baran was born Pesach Baran on April 29, 1926, in Grodno, then part of Poland and now in Belarus. He was the youngest of three children in a Lithuanian Jewish family, and Pesach, the Hebrew and Yiddish name for Passover, was the name he was given at birth. On May 11, 1928, when he was two, the family emigrated to the United States. They settled first in Boston and then in Philadelphia, where his father, Morris, known in the family as Moshe, opened a grocery store.
As a boy, Paul delivered groceries to his father’s customers in a small red wagon. It was a modest immigrant upbringing, and nothing in it suggested that the grocer’s youngest son would one day help lay the foundations of the internet.
An engineer in the first computer age
Baran studied electrical engineering at the Drexel Institute of Technology in Philadelphia, now Drexel University, and graduated in 1949. His first job was at the Eckert-Mauchly Computer Corporation, where he tested parts for the UNIVAC, the first commercial computer made in the United States. In 1955 he married Evelyn Murphy, and the couple moved to Los Angeles, where he worked for Hughes Aircraft on systems that processed radar data.
He took night classes at the University of California, Los Angeles, and earned a master’s degree in engineering in 1959 with a thesis on character recognition. His adviser, Gerald Estrin, remembered that Baran was the first student he ever had who went to the Patent Office in Washington to see whether his master’s work could be patented. From that day, Estrin said, he saw him not just as a serious student but as a young man looking to have an effect on the world. Baran began a doctorate but a heavy load of work and travel forced him to give it up.
A network that could survive
In 1959 Baran joined the RAND Corporation in Santa Monica, a research organisation that worked mainly for the United States Air Force. The Cold War was at its most dangerous, and military planners feared that a nuclear attack would destroy the few centralised switching centres on which telephone and command networks depended, cutting the country off from itself even if most of the wires survived. Baran took on the problem of designing a communications system that could keep working after such damage.
RAND’s own history describes the fear behind the work. During the Cuban missile crisis of 1962 the United States and the Soviet Union were building hair-trigger nuclear missile systems, and planners asked how any command and control network could survive an attack. Most telephone lines might remain intact, but the centralised switching centres would be destroyed. Baran’s critics dismissed his answer as unfeasible, but he persisted with colleagues at RAND.
His answer was to abandon the hub. Instead of routing every call through big central exchanges, he proposed a mesh of many simple nodes, each connected to several neighbours. Using computer simulations, his team randomly knocked out nodes and measured how much of the network stayed connected. They found that if each node had at least three links, the network remained remarkably resilient even when half the nodes were destroyed. Redundancy, not strength, was the key. His first report appeared in 1960, and the full design was published by RAND in 1964 in a series of reports called On Distributed Communications.
Breaking messages into blocks
The second half of Baran’s idea was just as radical. Rather than holding open a dedicated line for each conversation, as telephone networks did, he proposed cutting every message into small standard pieces, which he called message blocks. Each block would travel separately, hopping from node to node by whatever route was open at that moment, a method he nicknamed hot-potato routing. At the destination, the blocks would be put back together in order. If a node failed or was destroyed, the blocks simply went around it.
The design turned conventional engineering on its head. It put cheap, unreliable equipment in the middle of the network and placed the intelligence at the edges. In Baran’s words, it did not need expensive gold-plated components to be reliable. Engineers at AT&T, then the telephone monopoly, scoffed at the idea and, according to Vint Cerf, repeatedly said it would not work. In Britain, Donald Davies of the National Physical Laboratory independently arrived at the same concept a few years later and coined the word packet, which is the name that stuck. Baran was happy to acknowledge that they had come up with the same ingredients independently, and historians and the National Inventors Hall of Fame credit both men with inventing packet switching.
How it became the internet
When the Pentagon’s Advanced Research Projects Agency began building the ARPANET in 1969 to let researchers share distant computers, its planners drew on Baran’s RAND volumes among other sources. The first node was installed at UCLA, and the seventh at RAND itself. The ARPANET was eventually replaced by the internet, and packet switching still lies at the heart of how it works. Every email, video call, web page and mobile phone message today is broken into packets that find their own way across a mesh of routes and are reassembled at the other end, and the internet’s ability to route around failures descends in part from Baran’s search for a network that could survive a nuclear war. Within two years of its launch, RAND notes, the network’s users had turned it into something its builders had not planned: a high-speed electronic post office for exchanging messages.
Baran was always careful not to claim too much. He argued that credit for the internet should be spread widely, and compared technology to building a cathedral over centuries: each person lays a block on the old foundations, and it is easy to con yourself into believing you did the most important part, when in reality everything is tied to everything else.
A serial inventor and entrepreneur
Baran left RAND in 1968 to co-found the Institute for the Future, a non-profit research group devoted to long-range forecasting. He wrote about computers and privacy long before it was a public concern, and in 1976 took part in a review of the government’s proposed Data Encryption Standard. In a 1966 paper he described people shopping from home through a screen, clicking through a virtual department store.
He went on to start seven companies, five of which went public. Telebit, which he founded after conceiving its modem technology in the mid-1980s, was one of the first commercial products to use a technique called orthogonal frequency-division multiplexing, later widely used in DSL broadband and Wi-Fi. Metricom deployed Ricochet, the first public wireless mesh network for internet access, and Com21 was an early cable modem company. He is also credited with inventing the first doorway gun detector. Another of his ventures, PacketCable, spun off StrataCom to bring packetised voice to the telephone industry, leading to one of the first commercial products for the Asynchronous Transfer Mode networks that carried phone and data traffic. Late in life he applied packet thinking to radio, proposing simple ‘kindergarten rules’ by which many users could share the wireless spectrum, and he went on founding companies, among them GoBackTV and Plaster Networks, late into his life.
Jewish roots
Baran’s life began in one of the Jewish communities of Poland and Lithuania that were destroyed in the Holocaust, within fifteen years of his family’s departure. His family’s emigration in 1928, when he was a toddler, followed the path of hundreds of thousands of Eastern European Jews who sought safety and opportunity in American cities, and his father made his living as a small shopkeeper serving his neighbourhood.
Baran did not make his religious life a public subject, and the record of his Jewish background rests mainly on his origins: his birth name Pesach, his Lithuanian Jewish family, and the immigrant world of Philadelphia in which he grew up. He is listed among Jewish pioneers of computer science by jinfo.org, alongside Leonard Kleinrock and Robert Kahn.
The man
Colleagues described Baran as modest, generous and stubborn in the best sense. Vint Cerf said he was never afraid to go in directions counter to what everyone else thought was the right or only thing to do. Paul Saffo recalled that he saw innovation as a team process and avoided seeking credit for himself, and Robert Kahn called him one of the finest gentlemen he had ever met, creative to the very end.
His wife, Evelyn, died in 2007. Paul Baran died of complications from lung cancer at his home in Palo Alto, California, on March 26, 2011, at the age of 84. He was survived by his son, David, three grandchildren and his companion, Ruth Rothman.
Legacy
Baran received the IEEE Alexander Graham Bell Medal, the Marconi Prize, the National Medal of Technology and Innovation and induction into the National Inventors Hall of Fame and the Internet Hall of Fame. RAND’s president, James Thomson, said on his death that the world was a better place for the technologies Paul Baran invented and developed, and for his consistent concern with sensible public policies for their use.
His deepest legacy is an idea that now seems obvious: that a network is strongest when no single part is essential, and that information travels best in small pieces that can each find their own way. Billions of people rely on that idea every day without knowing his name.
Sources & further reading
Paul Baran, Internet Pioneer, Dies at 84, The New York Times · Paul Baran and the Origins of the Internet, RAND Corporation · Jewish computer and information scientists, jinfo.org · Paul Baran, Wikipedia · Researched from the sources above and checked against them. Spotted an error? Tell us.
A life of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.