David L. Mills

David Lennox Mills (June 3, 1938 – January 17, 2024) was an American computer engineer and professor emeritus at the University of Delaware.<ref name=bio/> He was an Internet pioneer who led the Gateway Algorithms and Data Structures (GADS) Task Force. He was known as the internet's "Father Time"<ref name="TheRegister-Obit" /> for designing the Network Time Protocol, which is intended to synchronize all participating computers across different computer systems and networks to within a few milliseconds of Coordinated Universal Time.

Early life and education

David Lennox Mills was born in Oakland, California, on June 3, 1938.<ref name="TheRegister-Obit" /><ref name="WaPoObit">Template:Cite news</ref> His mother, Adele (née Dougherty), was a pianist, and his father, Alfred, was an engineer.<ref name="NYTObit" /><ref name="WaPoObit" /> He had glaucoma since birth, but a surgeon saved some of the vision in his left eye when he was a child.<ref name="TheRegister-Obit">Template:Cite news</ref> He attended a school in San Mateo, California, for the visually impaired.<ref name=":0" />

Mills earned his PhD in Computer and Communication Sciences from the University of Michigan in 1971.<ref name=":0" /> While at Michigan, he worked on the ARPA-sponsored Conversational Use of Computers (CONCOMP) project and developed DEC PDP-8-based hardware and software to allow terminals to be connected over phone lines to an IBM 360 mainframe.<ref>The Data Concentrator Template:Webarchive, David Mills, May 1968, CONCOMP Project, University of Michigan, Ann Arbor</ref><ref>System/360 interface engineering report Template:Webarchive, D. L. Mills, November 1967, CONCOMP Project, University of Michigan, Ann Arbor</ref>

Career

In 1977, Mills began working at COMSAT on synchronizing the clocks of computers connected to ARPANET, inventing the Network Time Protocol (NTP).<ref name=":0"/><ref>RFC 778: DCNET Internet Clock Service, D. L. Mills, COMSAT Laboratories, April 18, 1981</ref><ref>RFC 958: Network Time Protocol (NTP) Template:Webarchive, D. L. Mills, M/A-COM Linkabit, September 1985</ref> NTP is intended to synchronize all participating computers to within a few milliseconds of Coordinated Universal Time (UTC).<ref>Template:Cite book</ref> He told The New Yorker in 2022 that he enjoyed working on synchronized time because no one else was working on it, giving him his own "little fief".<ref name=":0" /> In the mid-2000s, Mills turned over full control of the NTP reference implementation to Harlan Stenn.<ref name=":0" />

Mills was a contributor to the standards and software that came to be the Internet. He was the chairman of the Gateway Algorithms and Data Structures Task Force (GADS) and the first chairman of the Internet Architecture Task Force.<ref name="Quarterman"/> He invented the DEC LSI-11-based Fuzzball router that was used for the 56 kbit/s NSFNET (1985),<ref>"Fuzzball: The Innovative Router" Template:Webarchive, web page on NSF's "The Internet: Changing the Way We Communicate" Template:Webarchive</ref> and inspired the author of ping.<ref>Template:Cite web</ref> He authored 28 RFCs,<ref>Template:Cite web</ref> including two Internet Standards.<ref>Template:Cite web</ref>

In 1999, he was inducted as a fellow of the Association for Computing Machinery, and in 2002, he was inducted as a fellow of the Institute of Electrical and Electronics Engineers (IEEE) for contributions to network protocols and network timekeeping in the development of the Internet.<ref>Template:Cite web</ref> In 2008, Mills was elected a member of the National Academy of Engineering (NAE) for contributions to Internet timekeeping and the development of the Network Time Protocol. In 2013 he received the IEEE Internet Award "for significant leadership and sustained contributions in the research, development, standardization, and deployment of quality time synchronization capabilities for the Internet."<ref>"IEEE Internet Award Recipients: 2013 – David Mills" Template:Webarchive, IEEE Web site, accessed January 27, 2013</ref>

Mills was a professor emeritus at the University of Delaware, where he was a full professor from 1986 to 2008.<ref name=":0" /> He subsequently held an adjunct appointment at Delaware so that he could continue to teach.<ref>Template:Cite web</ref>

Personal life

Mills married Beverly Csizmadia in 1965.<ref name="NYTObit">Template:Cite news</ref>

Mills was an amateur radio operator, with callsign W3HCF.<ref name="TheRegister-Obit" /><ref>Dave Mills Personal Stuff Template:Webarchive, Web page, University of Delaware</ref><ref>"Amateur License – W3HCF – Mills, David L" Template:Webarchive, FCC Universal Licensing System</ref>

His vision began worsening around 2012, and by 2022 he was fully blind.<ref name=":0" /> Mills died in Newark, Delaware, on January 17, 2024, at age 85. Mills' wife, Beverly Jean Csizmadia Mills, died September 30, 2024, in Newark, Delaware.<ref>Template:Cite web</ref><ref>Template:Cite web </ref>

External links

• A Maze of Twisty, Turney Passages - Routing in the Internet Swamp. Lecture by David L. Mills at the University of Delaware. Given on May 26, 2005.
• Oral history interview with David L. Mills, Charles Babbage Institute, University of Minnesota. Interview covers Mills' invention of Network Time Protocol, his chairing the Internet Architecture Task Force, and interactions with colleagues including Vinton Cerf, David D. Clark, Jon Postel, Peter Kirstein, and David Farber.
• The Thorny Problem of Keeping the Internet's Time, New Yorker article by Nate Hopper. Popular article on NTP, covering some of the contribution and life of David Mills.