Determining and verifying the safety integrity level with security aspects

摘要

Safety and security aspects consist of two different group of functional requirements for the control and protection systems. It is the reason why the analyses of safety and security shouldnt be integrated directly. The paper proposes extension of the currently used methods of functional safety analyses. It can be done with inclusion of the level of information security assigned to the technical system. The article addresses some important issues of the functional safety analysis, namely the safety integrity level (SIL) verification of distributed control and protection systems with regard to security aspects. A method based on quantitative and qualitative information is proposed for the SIL (IEC 61508, 61511) verification with regard of the evaluation assurance levels (EAL) (ISO/IEC 15408) and the security assurance levels (SAL) (IEC 62443).