User:David E. Smyth

Perhaps best known as the software architect of all the Mars Rover missions, David has also contributed to computer science in the field of software fault tolerance, including leading the development team for what seems to be the first temporal fault tolerance system that worked even with no spatial redundancy (on a single processor). The effort also coined and trademarked the term "FDIR" for fault detection, isolation, and recovery. Unlike most fault tolerance schemes (based on TMR, or triple modular redundancy) this FDIR system used at least 4 votes, (the theoretical minimum for isolating faults). This temporal FDIR system was demonstrated experimentally on the B-1B. David contributed to open source projects include X11 and Wcl, the Widget Creation Library for Motif. He worked with a team of six to develop an entirely object oriented Unix (both SV and BSD) using the OOPL Mesa. He developed domain specific language systems for distributed system configuration and management, spacecraft simulation, interprocess communications, compiler semantics, and textual information analysis and simplification. He developed the deep space communication protocol used between Mars surface and Earth that was tolerant of delays. Unlike the competing Linklider/CFDP protocols, this protocol actually is built on a fundamentally sound foundation and does not violate the impossibility of distributed consensus (see Fisher et al) and has been proven effective for Spirit, Opportunity, and Curiosity rovers. He has presented papers at conferences in all US time zones, Europe, the Middle East, and Asia.