The Dependability Problem of Software Safety Kernel

Since software is being used in the control system largely,the possibility of serious damage resulting from a software defect is considerable and growing,and then the control systems are plunging into safety crisis.In fact,control systems are in urgent need of new safety assurance technologies.Safety kernel is a new concept of safety assurance.It e- merges,as the time requires.Of course,its dependability plays an important role on system.The present methods to im- prove the dependability of safety kernel are to limit its size and test.These methods prevent largely safety kernel from being used in complex systems.This paper at first analyzes comprehensively correctness requirements of safety kernel and the basis frame of safety-critical system.Then,based on all of these,a method that how to construct and improve the dependability of safety kernel is put forward from the safety requirements.Also This paper is a demonstration that safety kernel is a feasible and desirable technique for software in complex safety-critical systems.At last,taking the con trol system for the traffic lights as example,the whole process and its correctness have been achieved and proved.