Remembering Danny Cohen (1937 - 2019)

August 16, 2019
Danny Cohen Photo

2012 Internet Hall of Fame inductee Danny Cohen, whose work paved the way for voice over IP (VOIP) technology, died August 12th in Palo Alto, Calif., according to his family. He was 81.  

Writes The New York Times:  “Dr. Cohen, an Israeli immigrant who started out as a mathematician, is credited with designing the first real-time computerized flight simulation system, providing the experience of piloting a plane without having to leave the ground. When he took on the project, he told Wired magazine in 2012, the challenge was not just to master flying as a skill -- he later became an accomplished pilot -- but also to represent it graphically on a computer.”  

Cohen developed the flight simulator in 1967 on a general purpose computer (he also developed the first real-time radar simulator). This led to the creation of the Cohen-Sutherland computer graphics line clipping algorithms, created with Ivan Sutherland. Then, in 1973, he was the first to implement “packet-video” and “packet voice” (Network Voice Protocol) when he adapted the visual flight simulator to run over the ARPANET. It was the first application of packet switching to real-time applications. 

In addition to this work, as a researcher at the University of Southern California Information Sciences Institute (USC/ISI), he started and led several projects including FastXchange (e-commerce), digital library and ATOMIC, which was local area network technology.  Cohen and his research group under ARPA sponsorship developed the USC/ISI ATOMIC LAN, which was based on the Caltech Mosaic components. It was the research prototype for Myrinet, a high-performance system area network. He would go on to co-found Myricom, which commercialized Myrinet, and start the MOSIS project.

Cohen was also well-known for coining the computer terms Big Endian and Little Endian in his landmark article “On Holy Wars and a Plea for Peace,” which examines the proper byte order.