· Chief Scientist, Acorn Networks, Inc.1995–2001
· Research Scientist, Carlstedt Elektronik1992–1994
· Visiting Researcher, NASA Research Institute for Advanced Computer Science (RIACS)1987–
· Professor of Computer Science and Engineering, Emeritus, Massachusetts Institute of Technology1969–
· Doctor of Science, Massachusetts Institute of Technology1958–
· Faculty Member, Massachusetts Institute of Technology1958–1987
· Master of Science, Massachusetts Institute of Technology1954–
· Bachelor of Science, Massachusetts Institute of Technology1953–
· Cooperative Program Participant, Air Force Cambridge Research Laboratories
· Intern, Bell Telephone Laboratories