Together with Colin Fidge, he developed the vector clock algorithm, which allows one to generate a partial ordering of events in a distributed system and to detect causality violations.[1][2]
Publications
Distributed Algorithms for Termination Detection
Virtual Time and Global States of Distributed Systems
Detecting Causal Relationships in Distributed Computations: In Search of the Holy Grail
Social, Economic, and Ethical Implications of Ambient Intelligence and Ubiquitous Computing
Vom Verschwinden des Computers - Die Vision des Ubiquitous Computing
Das Internet der Dinge: Ubiquitous Computing und RFID in der Praxis. Visionen, Technologien, Anwendungen, Handlungsanleitungen ( 2005, Springer Berlin Heidelberg New York, ISBN3-540-24003-9) (as editor alongside Elgar Fleisch) [3]