Len Kleinrock, developer of queuing theory for packet switching

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Len Kleinrock with the IMP1

Kleinrock with the IMP1, the first node of the ARPANET

Len Kleinrock is often credited as one of the four fathers of the ARPANET, the precursor to the Internet, joining the likes of Larry Roberts, Robert Kahn, and Vinton Cerf.

Like other honorees, Kleinrock's work on what became today's Internet, was influenced by the academic world.

In a Ph.D thesis that he wrote in 1962 at MIT, Kleinrock wrote about his work on queuing theory. He then applied those theories to help develop packet switching, the bedrock technology of the Internet. Kleinrock would then apply his theories in his thesis in his work with the ARPANET.

While no one can recall the exact message that was sent, the beginning of the Internet can be traced back to one night on Oct. 29, 1969 at UCLA (University of California at Los Angeles). That night UCLA student programmer Charley Kline, at 10:30 p.m, sent the first message over the ARPANET network from the UCLA SDS Sigma 7 Host computer to another programmer, Bill Duvall, at the Stanford Research Institute's Augmentation Research Center, SDS 940 Host computer.

By December 1969, the remaining four-node network, which included sites at UC-Santa Barbara and the University of Utah's Computer Science Department, was completed.

In the late 1970s, Kleinrock conducted research in the late 1970s with his then-student Farouk Kamoun on hierarchical routing, another key technology used on the Internet.

Later, Kleinrock would serve as the chairman of the group that developed the report Toward a National Research Network to the U.S. Congress, which was used to develop the High Performance Computing Act of 1991. Both of these reports laid the groundwork of today's Internet.

Still operating as a computer science professor at UCLA, Kleinrock has received several awards for his work, including the National Medal of Science from President George W. Bush in 2008 and the Dan David Prize in 2010.