From 1981 to 1989, he acted as chief protocol architect in the development of the Internet, and chaired the Internet Activities Board, which later became the Internet Architecture Board. He has also served as chairman of the Computer Sciences and Telecommunications Board of the National Research Council.
In 1990 he was awarded the SIGCOMM Award in recognition of his major contributions to Internet protocol and architecture. Clark received in 1998 the IEEE Richard W. Hamming Medal.[2]
In 1996, Clark was elected a member of the National Academy of Engineering for the design and development of efficient implementation techniques for Internet protocols. In 1998, he was elevated to Fellow of the IEEE for leadership in the engineering and deployment of the protocols that embody the Internet.[3] In 2001, he was inducted as a Fellow of the Association for Computing Machinery.
Also in 2001, he was awarded the Telluride Tech Festival Award of Technology in Telluride, Colorado, and in 2011 the Internet & Society Lifetime Achievement Award from the Oxford Internet Institute at the Oxford University. In 2013, he was inducted into the Internet Hall of Fame.[4]
His recent research interests include what the architecture of the Internet will look like in the post-PC era as well as "extensions to the Internet to support real-time traffic, explicit allocation of service, pricing and related economic issues, and policy issues surrounding local loop employment".[1]
Clark has been credited with a popular statement in the computer science realm:[5]
We reject: kings, presidents, and voting. We believe in: rough consensus and running code.
— David D. Clark (1992)
In 1999, law professor Lawrence Lessig stated that "rough consensus and running code" had broad significance as "a manifesto that will define our generation.'[5] Clark's new ethos of consensus has become a widely used methodology software development today and replaced a more top down approach that existed in the 80s.