Dependable pervasive systems

Summary form only given. Present trends indicate that huge networked computer systems are likely to become pervasive, as information technology is embedded into virtually everything, and to be required to function essentially continuously. I believe that even today's (underused) "best practice" regarding the achievement of high dependability - reliability, availability, security, safety, etc. - from large networked computer systems will not suffice for future pervasive systems. I will give my perspective on the current state of research into the four basic dependability technologies: (i) fault prevention (to avoid the occurrence or introduction of faults), (ii) fault removal (through validation and verification), (iii) fault tolerance (so that failures do not necessarily occur even if faults remain), and (iv) fault forecasting (the means of assessing progress towards achieving adequate dependability). I will then argue that much further research is required on all four dependability technologies in order to cope with pervasive systems, identify some priorities, and discuss how this research could best be aimed at making system dependability into a "commodity" that industry can value and from which it can profit.