MULTIPROCESSOR CHECKING USING WATCHDOG PROCESSORS

A new control flow checking scheme is presented, based on assigned-sig nature checking using a watchdog processor. This scheme is suitable fo r a multitasking, multiprocessor environment. The hardware overhead is comparatively low because of three reasons: first, hierarchically str uctured, the scheme uses only a single watchdog processor to monitor p rocesses on multiple processors. Second, as an assigned-signature sche me, it does not require monitoring the instruction bus of the processo rs. Third, the run-time and reference signatures are embedded into the checked program; thus, in the watchdog processor neither a reference database nor a time-consuming search and compare engine is required.