Vulnerabilities, influences and interaction paths: failure data for integrated system risk analysis

We describe analysis methods for identifying and analyzing cross-subsystem interaction risks from subsystem connectivity information. These methods identify entities that can pose a hazard to a function if they can be propagated from the hazard source to the vulnerable function. The analysis method can assess combined impacts of multiple disabling influences on a vulnerable function. The analysis method also uses numerical estimates of hazard strength to calculate cumulative measures of impact severity. These methods can support design of more dependable and diagnosable systems and promote better communication among subsystem designers about risk. Identification of cross-subsystem hazard-vulnerability pairs and propagation paths will increase coverage of risk analysis and can help identify risk control and protection strategies