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Paul Baran, an engineer who helped create the technical underpinnings for the Arpanet, the government-sponsored precursor to today’s Internet, died Saturday night at his home in Palo Alto, Calif. He was 84.

Charles Dharapak/Associated Press

The engineer Paul Baran.

The cause was complications from lung cancer, said his son, David.

In the early 1960s, while working at the RAND Corporation in Santa Monica, Calif., Mr. Baran outlined the fundamentals for packaging data into discrete bundles, which he called “message blocks.” The bundles are then sent on various paths around a network and reassembled at their destination. Such a plan is known as “packet switching.”

Mr. Baran’s idea was to build a distributed communications network, less vulnerable to attack or disruption than conventional networks. In a series of technical papers published in the 1960s he suggested that networks be designed with redundant routes so that if a particular path failed or was destroyed, messages could still be delivered through another.

Mr. Baran’s invention was so far ahead of its time that in the mid-1960s, when he approached AT&T with the idea to build his proposed network, the company insisted it would not work and refused.

“Paul wasn’t afraid to go in directions counter to what everyone else thought was the right or only thing to do,” said Vinton Cerf, a vice president at Google who was a colleague and longtime friend of Mr. Baran’s. “AT&T repeatedly said his idea wouldn’t work, and wouldn’t participate in the Arpanet project,” he said.

In 1969, the Defense Department’s Advanced Research Projects Agency built the Arpanet, a network that used Mr. Baran’s ideas, and those of others. The Arpanet was eventually replaced by the Internet, and packet switching still lies at the heart of the network’s internal workings.

Paul Baran was born on April 29, 1926, in Grodno, Poland. His parents moved to the United States in 1928, and Mr. Baran grew up in Philadelphia. His father was a grocer, and as a boy, Paul delivered orders to customers in a small red wagon.

He attended the Drexel Institute of Technology, which later became Drexel University, where he earned a bachelor’s degree in electrical engineering in 1949. He took his first job at the Eckert-Mauchly Computer Corporation in Philadelphia, testing parts of radio tubes for an early commercial computer, the Univac. In 1955, he married Evelyn Murphy, and they moved to Los Angeles, where Mr. Baran took a job at Hughes Aircraft working on radar data processing systems. He enrolled in night classes at the University of California, Los Angeles.

Mr. Baran received a master’s degree in engineering from U.C.L.A. in 1959. Gerald Estrin, who was Mr. Baran’s adviser, said Mr. Baran was the first student he ever had who actually went to the Patent Office in Washington to investigate whether his master’s work, on character recognition, was patentable.

“From that day on, my expectations of him changed,” Dr. Estrin said. “He wasn’t just a serious student, but a young man who was looking to have an effect on the world.”

In 1959, Mr. Baran left Hughes to join RAND’s computer science department. He quickly developed an interest in the survivability of communications systems in the event of a nuclear attack, and spent the next several years at RAND working on a series of 13 papers — two of them classified — under contract to the Air Force, titled, “On Distributed Communications.”

About the same time that Mr. Baran had his idea, similar plans for creating such networks were percolating in the computing community. Donald Davies of the British National Physical Laboratory, working a continent away, had a similar idea for dividing digital messages into chunks he called packets.

“In the golden era of the early 1960s, these ideas were in the air,” said Leonard Kleinrock, a computer scientist at U.C.L.A. who was working on similar networking systems in the 1960s.

Mr. Baran left RAND in 1968 to co-found the Institute for the Future, a nonprofit research group specializing in long-range forecasting.

Mr. Baran was also an entrepreneur. He started seven companies, five of which eventually went public.

In recent years, the origins of the Internet have been subject to claims and counterclaims of precedence, and Mr. Baran was an outspoken proponent of distributing credit widely.

“The Internet is really the work of a thousand people,” he said in an interview in 2001.

“The process of technological developments is like building a cathedral,” he said in an interview in 1990. “Over the course of several hundred years, new people come along and each lays down a block on top of the old foundations, each saying, ‘I built a cathedral.’

“Next month another block is placed atop the previous one. Then comes along an historian who asks, ‘Well, who built the cathedral?’ Peter added some stones here, and Paul added a few more. If you are not careful you can con yourself into believing that you did the most important part. But the reality is that each contribution has to follow onto previous work. Everything is tied to everything else.”

Mr. Baran’s wife, Evelyn, died in 2007. In addition to his son, David, of Atherton, Calif., he is survived by three grandchildren; and his companion of recent years, Ruth Rothman.

 

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Comentário de Augusto de Franco em 2 abril 2011 às 5:45

Forerunner of the Internet: Early RAND Work in Distributed Networks and Packet Switching (1960-1965)

 

Para assistir o video clique no link abaixo:

http://www.rand.org/multimedia/video/2009/10/06/distributed_communi...

 

At a recent RAND Alumni Association event, RAND alumnus Paul Baran discussed his work on distributed networks and packet switching. In the early 1960s, RAND borrowed ideas about rerouting and redundancy that had been developed in neurobiology and applied them to strengthening the ability of Air Force communications to survive a nuclear attack. The resulting concept of "distributed communications" worked by breaking messages into smaller units of information that were sent independently through the communication system, each on the fastest path available to it, and reassembled at the end into the original message. When the Advanced Research Projects Agency, an agency of the U.S. Department of Defense, began looking for an information-sharing system, it arrived at the same concept of "packet switching" for what later became the Internet.

RAND Alumni Association

The RAND Alumni Association was established in 1992 as an independent organization. Its primary purpose is to provide a forum for social and professional activities of former and current RANDites. Since then, we have grown from the first 100 Charter Members to more than 2,000 strong, across the United States and around the world. Every three years, a 12-member volunteer Board of Directors is elected to guide and govern the Association, with support provided by RAND's Development Office.

 

Comentário de Augusto de Franco em 2 abril 2011 às 5:44

Obituary: Paul Baran, RAND Researcher and Pioneer of the Internet

http://www.rand.org/news/press/2011/03/28/index1.html

FOR RELEASE

Monday
March 28, 2011

Paul Baran, who helped develop the building blocks of the Internet during the 1960s while working as a researcher at the RAND Corporation, died March 26 at his home in Palo Alto, Calif., from complications relating to lung cancer. He was 84.

RAND colleagues remembered Baran as a friendly and brilliant scientist who cared as much about the application of technology as he did about its development.

"Our world is a better place for the technologies Paul Baran invented and developed, and also because of his consistent concern with appropriate public policies for their use," said James A. Thomson, president and CEO of RAND. "Paul believed that much of the future is shaped by the development of technology and that it was quite appropriate that a lot of engineers and scientists be a part of an institution that's concerned with the future of public policy."

Baran left RAND in 1968, but he remained an active supporter of the non-profit, non-partisan research organization and the RAND Alumni Association. He frequently attended public policy forums and other events at RAND.

Natalie Crawford, a RAND senior fellow, recalled Baran as "a true visionary" who made some startlingly prescient predictions in a 1968 RAND report about how people would use the computer at home and for commerce.

"He was a kind and very humble man," she said. "He was a great mentor. He didn't care about who got credit. When he visited RAND in the summer of 2009 and presented a seminar to the Alumni Association on his work that led to packet switching, he said a lot of people contributed in important ways to this discovery, that it wasn't his alone. And then he closed with the quote: "If you see a frog sitting on top of a flag pole, you know it didn't get up there by itself." That typified Paul. We are all fortunate to have benefitted from Paul's many contributions and his friendship over the years, but he will be sorely missed."

Baran was born in Poland on April 28, 1926. In 1928, his family moved to the United States. He attended Drexel Institute of Technology (now Drexel University), where he earned a degree in electrical engineering in 1949. He went to work for Eckert-Mauchly Computer Corporation in Philadelphia, testing parts of radio tubes for an early commercial computer, the Univac.

He was married to Evelyn Murphy in 1955 and moved to Los Angeles, where he worked for the Hughes Aircraft Company. Taking night classes at UCLA, he earned a master's degree in engineering and joined the computer science department at the RAND Corporation in 1959.

Willis Ware, a retired RAND researcher, was chairman of the computer science department at RAND during Baran's tenure and said what he remembered most about his colleague was "his patience in dealing with people who didn't believe in his work — like AT&T [in the 1960s]. I think nobody really appreciated the importance of his work at the time."

At that time, RAND focused mostly on Cold War-related military issues. A looming concern was that neither the long-distance telephone network nor the basic military command-and-control system would survive a nuclear attack. Although most of the links would be undamaged, the centralized switching facilities would be destroyed by enemy weapons. Consequently, Baran conceived a system that had no centralized switches and could operate even if many of its links and switching nodes had been destroyed.

Baran envisioned a network of unmanned nodes that would act as switches, routing information from one node to another to their final destinations. The nodes would use a scheme Baran called "hot-potato routing" or distributed communications.

Baran also developed the concept of dividing information into "message blocks" before sending them out across the network. Each block would be sent separately and rejoined into a whole when they were received at their destination. The British computer scientist Donald Davies independently devised a similar system, but he called the message blocks "packets," a term that was eventually adopted instead of Baran's message blocks. The technology is known today as "packet switching."

In 1969, this distributed concept underwent its first large-scale test, with the first node installed at UCLA and the seventh node at RAND in Santa Monica. Funded by the Advanced Research Projects Agency and called ARPANET, it was intended for scientists and researchers who wanted to share one another's computers remotely. Within two years, however, the network's users had turned it into something unforeseen: a high-speed, electronic post office for exchanging everything from technical to personal information.

In 1983, the rapidly expanding network broke off from its military part, which became MILNET. The remainder became what was called ARPANET. In 1989, the ARPANET moniker was retired in favor of the "Internet," which had also been described as the "information superhighway."

Baran left RAND in 1968 to co-found the Institute for the Future, a nonprofit research group specializing in long-range forecasting. He also started seven companies, five of which eventually became publicly-traded companies.

Baran's papers will be donated to Stanford University, according to his family.

Baran's wife, Evelyn, died in 2007. He is survived by his son and daughter-in-law, David and Jane Baran of Atherton, Calif.; three grandchildren; and his companion, Ruth Rothman.

Comentário de Augusto de Franco em 2 abril 2011 às 5:37

Paul Baran and the Origins of the Internet

 

http://www.rand.org/about/history/baran.list.html

 

In 1962, a nuclear confrontation seemed imminent. The United States (US) and the Union of Soviet Socialist Republics (USSR) were embroiled in the Cuban missile crisis. Both the US and the USSR were in the process of building hair-trigger nuclear ballistic missile systems. Each country pondered post-nuclear attack scenarios.

US authorities considered ways to communicate in the aftermath of a nuclear attack. How could any sort of "command and control network" survive? Paul Baran, a researcher at RAND, offered a solution: design a more robust communications network using "redundancy" and "digital" technology.

At the time, naysayers dismissed Baran's idea as unfeasible. But working with colleagues at RAND, Baran persisted. This effort would eventually become the foundation for the World Wide Web.

centralized switching facilities
centralized
distributed switching facilities
distributed

Baran was born in Poland in 1926. In 1928, his family moved to the US. He attended Drexel University where he earned a degree in electrical engineering. Afterward, Baran married and moved to Los Angeles where he worked for the Hughes Aircraft Company. Taking night classes at UCLA, he earned an engineering master's degree in 1959--the same year he joined RAND.

At that time, RAND focused mostly on Cold War-related military issues. A looming concern was that neither the long-distance telephone plant, nor the basic military command and control network would survive a nuclear attack. Although most of the links would be undamaged, the centralized switching facilities would be destroyed by enemy weapons. Consequently, Baran conceived a system that had no centralized switches and could operate even if many of its links and switching nodes had been destroyed.

Baran envisioned a network of unmanned nodes that would act as switches, routing information from one node to another to their final destinations. The nodes would use a scheme Baran called "hot-potato routing" ordistributed communications.

Baran also developed the concept of dividing information into "message blocks" before sending them out across the network. Each block would be sent separately and rejoined into a whole when they were received at their destination. A British man named Donald Davies independently devised a very similar system, but he called the message blocks "packets," a term that was eventually adopted instead of Baran's message blocks.

This method of "packet switching" is a rapid store-and-forward design. When a node receives a packet it stores it, determines the best route to its destination, and sends it to the next node on that path. If there was a problem with a node (or if it had been destroyed) packets would simply be routed around it.

In a recent interview with Wired magazine, Baran discussed his vision of how the new technology might be used. "Around December 1966, I presented a paper at the American Marketing Association called 'Marketing in the Year 2000.' I described push-and-pull communications and how we're going to do our shopping via a television set and a virtual department store. If you want to buy a drill, you click on Hardware and that showsTools and you click on that and go deeper."

In 1969, this "distributed" concept was given its first large-scale test, with the first node installed at UCLA and the seventh node at RAND in Santa Monica. Funded by the Advanced Research Projects Agency and called ARPANET, it was intended for scientists and researchers who wanted to share one another's computers remotely. Within two years, however, the network's users had turned it into something unforeseen: a high-speed, electronic post office for exchanging everything from technical to personal information.

In 1983, the rapidly expanding network broke off from its military part, which became MILNET. The remainder became what was called ARPANET. In 1989, the ARPANET moniker was retired in favor the "Internet," which had also been described as the "information superhighway." These days, the Internet continues to expand, stringing together the World Wide Web, an all-encompassing, affordable, universal multimedia communications network (see related RAND Review article).

Today, RAND continues to conduct research in this area. CEO and President of RAND Jim Thomson recently recalled Baran's contributions. "Our world is a better place for the technologies Paul Baran has invented and developed, and also because of his consistent concern with appropriate public policies for their use."

On Distributed Communications Series

 

http://www.rand.org/about/history/baran-list.html

Publications in the "On Distributed Communications" Series

An electrical engineer by training, Paul Baran worked for Hughes Aircraft Company's systems group before joining RAND in 1959. While working at RAND on a scheme for U.S. telecommunications infrastructure to survive a "first strike," Baran conceived of the Internet and digital packet switching, the Internet's underlying data communications technology. His concepts are still employed today; just the terms are different. His seminal work first appeared in a series of RAND studies published between 1960 and 1962 and then finally in the tome "On Distributed Communications," published in 1964.

Since the early 1970s as an entrepreneur and private investor, Baran has founded or co-founded several high-tech telecommunications firms. He is currently chairman and co-founder of Com21, Inc., a Silicon Valley-based manufacturer of cable TV modems for high-speed, high-bandwidth Internet access. He is also a co-founder of the Institute for the Future. Baran holds several patents and has received numerous professional honors including an honorary doctorate from his alma mater Drexel University (BS '49). He has a master's degree in engineering from UCLA.


The following documents in this series are presented in their entirety in HTML format.

I. Introduction to Distributed Communications Networks

Paul Baran, RM-3420-PR

Introduces the system concept and outlines the requirements for and design considerations of the distributed digital data communications network. Considers especially the use of redundancy as a means of withstanding heavy enemy attacks. A general understanding of the proposal may be obtained by reading this volume and Vol. XI.

II. Digital Simulation of Hot-Potato Routing in a Broadband Distrib...

Sharla P. Boehm and Paul Baran, RM-3103-PR

Describes a computer simulation of the message routing scheme proposed. The basic routing doctrine permitted a network to suffer a large number of breaks, then reconstitute itself by rapidly relearning to make best use of the surviving links.

III. Determination of Path-Lengths in a Distributed Network

J. W. Smith, RM-3578-PR

Continues model simulation reported in Vol. II. The program was rewritten in a more powerful computer language allowing examination of larger networks. Modification of the routing doctrine by intermittently reducing the input data rate of local traffic reduced to a low level the number of message blocks taking excessively long paths. The level was so low that a deterministic equation was required in lieu of Monte Carlo to examine the now rare event of a long message block path. The results of both the simulation and the equation agreed in the area of overlapping validity.

IV. Priority, Precedence, and Overload

Paul Baran, RM-3638-PR

The creation of dynamic or flexible priority and precedence structures within a communication system handling a mixture of traffic with different data rate, urgency, and importance levels is discussed. The goal chosen is optimum utilization of the communications resource within a seriously degraded and overloaded network.

V. History, Alternative Approaches, and Comparisons

Paul Baran, RM-3097-PR

A background paper acknowledging the efforts of people in many fields working toward the development of large communications systems where system reliability and survivability are mandatory. A consideration of terminology is designed to acquaint the reader with the diverse, sometimes conflicting, definitions used. The evolution of the distributed network is traced, and a number of earlier hardware proposals are outlined.

VI. Mini-Cost Microwave

Paul Baran, RM-3762-PR

The technical feasibility of constructing an extremely low-cost, all-digital, X- or Ku -band microwave relay system, operating at a multi-megabit per second data rate, is examined. The use of newly developed varactor multipliers permits the design of a miniature, all-solid-state microwave repeater powered by a thermoelectric converter burning L-P fuel.

VII. Tentative Engineering Specifications and Preliminary Design fo...

Paul Baran, RM-3763-PR

High-speed, or "hot-potato," store-and-forward message block relaying forms the heart of the proposed information transmission system. The Switching Nodes are the units in which the camplex processing takes place. The node is described in sufficient engineering detail to estimate the components required. Timing calculations, together with a projected implementation scheme, provide a strong toundation for the belief that the construction and use of the node is practical.

VIII. The Multiplexing Station

Paul Baran, RM-3764-PR

A description of the Multiplexing Stations which connect subscribers to the Switching Nodes. The presentation is in engineering detail, demonstrating how the network will simultaneously process traffic from up to 1024 separate users sending a mixture of start-stop teletypewriter, digital voice, and other synchronous signals at various rates.

IX. Security, Secrecy, and Tamper-Free Considerations

Paul Baran, RM-3765-PR

Considers the security aspects of a system of the type proposed, in which secrecy is of paramount importance. Describes the safeguards to be built into the network, and evaluates the premise that the existence of "spies" within the supposedly secure system must be anticipated. Security provisions are based on the belief that protection is best obtained by raising the "price" of espied information to a level which becomes excessive. The treatment of the subject is itself unclassified.

X. Cost Estimate

Paul Baran, RM-3766-PR

A detailed cost estimate for the entire proposed system, based on an arbitrary network configuration of 400 Switching Nodes, servicing 100,000 simultaneous users via 200 Multiplexing Stations. Assuming a usable life of ten years, all costs, including operating costs, are estimated at about $60,000,000 per year.

XI. Summary Overview

Paul Baran, RM-3767-PR

Summarizes the system proposal, highlighting the more important features. Considers the particular advantages of the distributed network, and conuents on disadvantages. An outline is given of the manner in which future research aimed at an actual implementation of the network might be conducted. Together with the introductory volume, it provides a general description of the entire system concept.



Comentário de Augusto de Franco em 29 março 2011 às 7:10

Paul Baran ha muerto, larga vida a su legado

Paul Baran, que en 1964 ideó la estructura de comunicaciones de Arp... que vendría a devenir nuestra Internet, con su neutralidad, y a revolucionar las topologías de la información y, por extensión, el mundo en que vivimos, falleció el pasado sábado a los 84 años de edad. Su legado, los mundos más libres que sus desarrollos hacen posibles, le sobreviven desde ya y la sencilla demostración nos la proporciona el hecho de que los indianos al completo nos enteremos de esto gracias a un post de Gonzalo en Madrid que nos lleva al New York Times y que nosotros estamos leyendo desde Montevideo.

Comentário de Augusto de Franco em 29 março 2011 às 7:09

El legado de Paul Baran

Paul Baran, uno de los padres de la web, falleció ayer a los ochenta y cuatro años de edad. Es la persona que ideó la arquitectura distribuida de la red con el propósito de hacerla más resiliente al no depender el flujo de la información de nodos que centralizaran su paso. Las consecuencias de ello han sido de enorme calado. La industria audiovisual, las culturales y los medios de información en general son una de las víctimas evidentes tal y como están articuladas hoy día de los efectos secundarios de todo ello. No así la cultura, se diga lo que se diga. Estoy trabajando en colaboración con Las Indias en un minidocumental animado para explicar lo que supuso la decisión de Baran y la extensón de las redes distribuidas en el entorno social: a ver si les gusta el story.

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