Handling Temporal Faults in Ada 2005

Hard real-time systems have stringent deadline requirements, which can be guaranteed at system design time by restricting the computational model so that a careful analysis of execution-time budgets and response-time values can be performed. However, design-time guarantees are not enough in many high-integrity systems, in which some degree of run-time fault-tolerance has to be implemented as well. This paper deals with run-timemechanisms for temporal fault detection and recovery, based on some of the new features available in Ada 2005. Fault detection mechanisms are based on execution-time clocks and timers, and timing events. Fault recovery schemes are application-dependent, but somebasic patterns are proposed that can be used to develop such kinds of mechanisms.