Paul Baran

Last updated
Paul Baran
Paul Baran.jpg
Born(1926-04-29)April 29, 1926
DiedMarch 26, 2011(2011-03-26) (aged 84)
Citizenship Poland, United States
Alma mater UCLA (M.S., 1959)
Drexel Institute of Technology (B.S., 1949)
Philadelphia
Known for Packet Switching
Spouse(s)Evelyn Murphy Baran, PhD
Awards IEEE Alexander Graham Bell Medal (1990)
Computer History Museum Fellow (2005) [1]
Marconi Prize (1991)
NMTI (2007)
National Inventors Hall of Fame
Scientific career
Institutions RAND Corporation

Paul Baran (born Pesach Baran /ˈbærən/ ; April 29, 1926 – March 26, 2011) was a Polish-American engineer who was a pioneer in the development of computer networks. He was one of the two independent inventors of packet switching, [2] which is today the dominant basis for data communications in computer networks worldwide, and went on to start several companies and develop other technologies that are an essential part of modern digital communication.

Computer network collection of autonomous computers interconnected by a single technology

A computer network is a digital telecommunications network which allows nodes to share resources. In computer networks, computing devices exchange data with each other using connections between nodes. These data links are established over cable media such as wires or optic cables, or wireless media such as Wi-Fi.

Packet switching a method of grouping data which is transmitted over a digital network into packets

Packet switching is a method of grouping data that is transmitted over a digital network into packets. Packets are made of a header and a payload. Data in the header are used by networking hardware to direct the packet to its destination where the payload is extracted and used by application software. Packet switching is the primary basis for data communications in computer networks worldwide.

Contents

Early life

He was born in Grodno (then Second Polish Republic, since 1945 part of Belarus) on April 29, 1926. [3] [4] He was the youngest of three children in a Polish-Jewish family, [5] with the Yiddish given name "Pesach". His family moved to the United States on May 11, 1928, [6] settling in Boston and later in Philadelphia, where his father, Morris "Moshe" Baran (1884–1979), opened a grocery store. He graduated from Drexel University (then called Drexel Institute of Technology) in 1949, with a degree in electrical engineering. He then joined the Eckert-Mauchly Computer Company, where he did technical work on UNIVAC models, the first brand of commercial computers in the United States. [7] In 1955 he married Evelyn Murphy, moved to Los Angeles, and worked for Hughes Aircraft on radar data processing systems. He obtained his master's degree in engineering from UCLA in 1959, with advisor Gerald Estrin while he took night classes. His thesis was on character recognition. [3] While Baran initially stayed on at UCLA to pursue his doctorate, a heavy travel and work schedule forced him to abandon his doctoral work. [8]

Grodno Place in Grodno Region, Belarus

Hrodna, or Grodno is a city in western Belarus. It is located on the Neman close to the borders of Poland and Lithuania. It has 373,547 inhabitants. It is the capital of Grodno Region and Grodno District.

Second Polish Republic 1918-1939 republic in Eastern Europe

The Second Polish Republic, commonly known as interwar Poland, refers to the country of Poland in the period between the First and Second World Wars (1918–1939). Officially known as the Republic of Poland, the state was re-established in 1918, in the aftermath of World War I. The Second Republic ceased to exist in 1939, when Poland was invaded by Nazi Germany, the Soviet Union and the Slovak Republic, marking the beginning of the European theatre of World War II.

Belarus country in Eastern Europe

Belarus, officially the Republic of Belarus, formerly known by its Russian name Byelorussia or Belorussia, is a landlocked country in Eastern Europe bordered by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital and most populous city is Minsk. Over 40% of its 207,600 square kilometres (80,200 sq mi) is forested. Its major economic sectors are service industries and manufacturing. Until the 20th century, different states at various times controlled the lands of modern-day Belarus, including the Principality of Polotsk, the Grand Duchy of Lithuania, the Polish–Lithuanian Commonwealth, and the Russian Empire.

Packet switched network design

After joining the RAND Corporation in 1959, Baran took on the task of designing a "survivable" communications system that could maintain communication between end points in the face of damage from nuclear weapons during the Cold War. [9] Then, most American military communications used high-frequency connections, which could be put out of action for many hours by a nuclear attack. Baran decided to automate RAND Director Franklin R. Collbohm's previous work with emergency communication over conventional AM radio networks and showed that a distributed relay node architecture could be survivable. The Rome Air Development Center soon showed that the idea was practicable. [10]

RAND Corporation non-profit organisation in the USA

RAND Corporation is an American nonprofit global policy think tank created in 1948 by Douglas Aircraft Company to offer research and analysis to the United States Armed Forces. It is financed by the U.S. government and private endowment, corporations, universities and private individuals. The company has grown to assist other governments, international organizations, private companies and foundations, with a host of defense and non-defense issues, including healthcare. RAND aims for interdisciplinary and quantitative problem solving by translating theoretical concepts from formal economics and the physical sciences into novel applications in other areas, using applied science and operations research.

Nuclear weapon Explosive device that derives its destructive force from nuclear reactions

A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or from a combination of fission and fusion reactions. Both bomb types release large quantities of energy from relatively small amounts of matter. The first test of a fission ("atomic") bomb released an amount of energy approximately equal to 20,000 tons of TNT (84 TJ). The first thermonuclear ("hydrogen") bomb test released energy approximately equal to 10 million tons of TNT (42 PJ). A thermonuclear weapon weighing little more than 2,400 pounds (1,100 kg) can release energy equal to more than 1.2 million tons of TNT (5.0 PJ). A nuclear device no larger than traditional bombs can devastate an entire city by blast, fire, and radiation. Since they are weapons of mass destruction, the proliferation of nuclear weapons is a focus of international relations policy.

Cold War Geopolitical tension after World War II between the Eastern and Western Bloc

The Cold War was a period of geopolitical tension between the Soviet Union with its satellite states, and the United States with its allies after World War II. The historiography of the conflict began between 1946 and 1947. The Cold War began to de-escalate after the Revolutions of 1989. The collapse of the USSR in 1991 was the end of the Cold War. The term "cold" is used because there was no large-scale fighting directly between the two sides, but they each supported major regional conflicts known as proxy wars. The conflict split the temporary wartime alliance against Nazi Germany and its allies, leaving the USSR and the US as two superpowers with profound economic and political differences.

Using the minicomputer technology of the day, Baran and his team developed a simulation suite to test basic connectivity of an array of nodes with varying degrees of linking. That is, a network of n-ary degree of connectivity would have n links per node. The simulation randomly "killed" nodes and subsequently tested the percentage of nodes that remained connected. The result of the simulation revealed that networks in which n ≥ 3 had a significant increase in resilience against even as much as 50% node loss. Baran's insight gained from the simulation was that redundancy was the key. [11] His first work was published as a RAND report in 1960, [12] with more papers generalizing the techniques in the next two years. [13]

After proving survivability, Baran and his team needed to show proof of concept for that design so that it could be built. That involved high-level schematics detailing the operation, construction, and cost of all the components required to construct a network that leveraged the new insight of redundant links. The result was one of the first store-and-forward data layer switching protocols, a link-state/distance vector routing protocol, and an unproved connection-oriented transport protocol. Explicit detail of the designs can be found in the complete series of reports On Distributed Communications, published by RAND in 1964. [14]

The design flew in the face of telephony design of the time by placing inexpensive and unreliable nodes at the center of the network and more intelligent terminating 'multiplexer' devices at the endpoints. In Baran's words, unlike the telephone company's equipment, his design did not require expensive "gold plated" components to be reliable. The Distributed Network that Baran introduced was intended to route around damage. It provided connection to others through many points, not one centralized connection. Fundamental to the scheme was the division of the information into "blocks" before they were sent out across the network. That enabled the data to travel faster and communications lines to be used more efficiently. Each block was sent separately, traveling different paths and rejoining into a whole when they were received at their destination.

Selling the idea

After the publication of On Distributed Communications, he presented the findings of his team to a number of audiences, including AT&T engineers (not to be confused with Bell Labs engineers, who at the time provided Paul Baran with the specifications for the first generation of T1 circuit that he used as the links in his network design proposal). In subsequent interviews, Baran mentioned how the AT&T engineers scoffed at his idea of non-dedicated physical circuits for voice communications, at times claiming that Baran simply did not understand how voice telecommunication worked. [15]

Donald Davies, at the National Physical Laboratory in the United Kingdom, also thought of the same idea [3] [16] and implemented a trial network. While Baran used the term "message blocks" for his units of communication, Davies used the term "packets," as it was capable of being translated into languages other than English without compromise. [17] He applied the concept to a general-purpose computer network. Davies's key insight came in the realization that computer network traffic was inherently "bursty" with periods of silence, compared with relatively-constant telephone traffic. It was in fact Davies's work on packet switching, not Baran's, that initially caught the attention of the developers of ARPANET at a conference in Gatlinburg, Tennessee, in October 1967. [18] Baran was happy to acknowledge that Davies had come up with the same idea as him independently. In an e-mail to Davies, he wrote:

You and I share a common view of what packet switching is all about, since you and I independently came up with the same ingredients. [19]

Leonard Kleinrock, a contemporary working on analyzing message flow using queueing theory, developed a theoretical basis for the operation of message switching networks in his proposal for a Ph.D. thesis in 1961-2, published as a book in 1964. [20] He later applied this theory to model the performance of packet switching networks. However, the contribution of Kleinrock's early work as a theoretical basis of packet switching is disputed by some, [21] [22] [23] including Robert Taylor, [24] Baran [25] and Davies. [26] The US National Inventors Hall of Fame, which recognizes inventors who hold a US patent of highly-significant technology, records Paul Baran and Donald Davies as the inventors of digital packet switching. [27] [28]

In 1969, when the US Advanced Research Projects Agency (ARPA) started developing the idea of an internetworked set of terminals to share computing resources, the reference materials that they considered included Baran and the RAND Corporation's "On Distributed Communications" volumes. [3] The resiliency of a packet-switched network that uses link-state routing protocols, which are used on the Internet, stems in some part from the research to develop a network that could survive a nuclear attack. [3] [29]

Later work

In 1968, Baran was a founder of the Institute for the Future and was then involved in other networking technologies developed in Silicon Valley. He participated in a review of the NBS proposal for a Data Encryption Standard in 1976, along with Martin Hellman and Whitfield Diffie of Stanford University. [30] In the early 1980s, Baran founded PacketCable, Inc, "to support impulse-pay television channels, locally generated videotex, and packetized voice transmission." [31] [32] PacketCable, also known as Packet Technologies, spun off StrataCom to commercialize his packet voice technology for the telephony market. That technology led to the first commercial pre-standard Asynchronous Transfer Mode product. He founded Telebit after conceiving its discrete multitone modem technology in the mid-1980s. It was one of the first commercial products to use orthogonal frequency-division multiplexing, which was later widely deployed in DSL modems and Wi-Fi wireless modems. In 1985, Baran founded Metricom, the first wireless Internet company, which deployed Ricochet, [4] the first public wireless mesh networking system. In 1992, he also founded Com21, an early cable modem company. [7] After Com21, Baran founded and was president of GoBackTV, which specializes in personal TV and cable IPTV infrastructure equipment for television operators. [33] Most recently, he founded Plaster Networks, providing an advanced solution for connecting networked devices in the home or small office through existing wiring. [34]

Baran extended his work in packet switching to wireless-spectrum theory, developing what he called "kindergarten rules" for the use of wireless spectrum. [35]

In addition to his innovation in networking products, he is also credited with inventing the first doorway gun detector. [7] [36]

He received an honorary doctorate when he gave the commencement speech at Drexel in 1997. [37]

Death

Baran died in Palo Alto, California, at the age of 84 on March 26, 2011 [3] [38] from complications caused by lung cancer. [29] Upon his death, RAND President James Thomson, stated, "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." [38]

One of the fathers of the Internet, Vinton Cerf, stated, "Paul wasn't afraid to go in directions counter to what everyone else thought was the right or only thing to do." [29] According to Paul Saffo, Baran also believed that innovation was a "team process" and avoided seeking credit for himself. [36] On hearing news of his death, Robert Kahn, co-inventor of the Internet, said: "Paul was one of the finest gentlemen I ever met and creative to the very end."

Awards and honors

See also

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References

  1. Paul Baran 2005 Fellow Archived 2015-01-03 at the Wayback Machine
  2. Harris
  3. 1 2 3 4 5 6 Katie Hafner (March 27, 2011). "Paul Baran, Internet Pioneer, Dies at 84". The New York Times .
  4. 1 2 Nathan Brewer; et al. (March 28, 2011). "Paul Baran". IEEE Global History Network. New York: IEEE . Retrieved March 28, 2011.
  5. Georgi Dalakov. "Paul Baran". History of Computers web site. Retrieved March 31, 2011.
  6. David Ira Snyder (August 4, 2009). "Morris "Moshe" Baran (1884–1979)". Genealogy of the Baran family. Geni.com web site. Retrieved March 29, 2011.
  7. 1 2 3 4 "Paul Baran - Franklin Laureate Database". The Franklin Institute Awards - Laureate Database. Philadelphia, PA: The Franklin Institute . Retrieved March 29, 2011.
  8. Hafner, Katie; Lyon, Matthew (1996). Where wizards stay up late : the origins of the Internet (1st Touchstone ed.). New York: Simon and Schuster. p. 54. ISBN   0-684-81201-0.
  9. "Internet pioneer Paul Baran passes away". BBC News . March 28, 2011. Retrieved March 28, 2011.
  10. Brand, Stewart (March 2001). "Founding Father". Wired . New York: Condé Nast Digital. 9 (3). ISSN   1059-1028. OCLC   433726773 . Retrieved March 27, 2011. Paul Baran conceived the Internet's architecture at the height of the Cold War. Forty years later, he says the Net's biggest threat wasn't the USSR—it was the phone company Stewart Brand's interviews Paul Baran about his work at RAND on survivable networks.
  11. "Paul Baran and the Origins of the Internet". RAND corporation. Retrieved March 29, 2011.
  12. Paul Baran (1960). "Reliable Digital Communications Systems Using Unreliable Network Repeater Nodes". RAND Corporation papers, document P-1995. Retrieved March 29, 2011.
  13. Paul Baran (1962). "On Distributed Communications Networks". RAND Corporation papers, document P-2626. Retrieved March 29, 2011.
  14. Paul Baran; et al. (1964). "On Distributed Communications". Rand. Archived from the original on June 15, 2006.
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  16. Georgi Dalakov. "Donald Davies". History of Computers web site. Retrieved March 31, 2011.
  17. Harris , p. 6
  18. Isaacson, Walter (2014). The Innovators: How a Group of Hackers, Geniuses, and Geeks Created the Digital Revolution. Simon & Schuster. p. 237. ISBN   9781476708690.
  19. Harris, p. 9
  20. Kleinrock, Leonard (1961), "Information flow in large communication nets", RLE Quarterly Progress Report (1)
  21. Alex McKenzie (2009), Comments on Dr. Leonard Kleinrock's claim to be "the Father of Modern Data Networking" , retrieved April 23, 2015 "...there is nothing in the entire 1964 book that suggests, analyzes, or alludes to the idea of packetization."
  22. Isaacson, Walter (2014). The Innovators: How a Group of Hackers, Geniuses, and Geeks Created the Digital Revolution. Simon & Schuster. p. 245. ISBN   9781476708690. This led to an outcry among many of the other Internet pioneers, who publicly attacked Kleinrock and said that his brief mention of breaking messages into smaller pieces did not come close to being a proposal for packet switching
  23. Harris
  24. "Birthing the Internet: Letters From the Delivery Room; Disputing a Claim". New York Times. 22 November 2001. Retrieved 10 September 2017. Authors who have interviewed dozens of Arpanet pioneers know very well that the Kleinrock-Roberts claims are not believed.
  25. Katie Hefner (November 8, 2001), "A Paternity Dispute Divides Net Pioneers", New York Times, The Internet is really the work of a thousand people," Mr. Baran said. "And of all the stories about what different people have done, all the pieces fit together. It's just this one little case that seems to be an aberration.
  26. Donald Davies (2001), "A Historical Study of the Beginnings of Packet Switching", Computer Journal, British Computer Society, I can find no evidence that he understood the principles of packet switching.
  27. "Inductee Details - Paul Baran". National Inventors Hall of Fame. Retrieved 6 September 2017.
  28. "Inductee Details - Donald Watts Davies". National Inventors Hall of Fame. Retrieved 6 September 2017.
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  43. 2012 Inductees, Internet Hall of Fame website. Last accessed April 24, 2012
Awards
Preceded by
Gerald R. Ash and Billy B. Oliver
IEEE Alexander Graham Bell Medal
1990
Succeeded by
C. Chapin Cutler, John O. Limb and Arun Netravali