1 National Workshop on Aviation Software Systems: Design for Certifiably Dependable Systems Natasha Neogi October 5-6, 2006 Arlington, VA

2 The Next Generation Air Transportation System

3 Security and Safety Issues  Security and Safety are highest priorities Self-inflicted DOS or DOI not an option Liveness (physical systems must obey dynamic constraints) Most access/authentication systems not appropriate  Diversity involves multiple technologies  Integrity and Availability can be more important than Confidentiality Safety and Security Properties can lead to Competing Requirements

4 Sustainment & Retirement Requirements Specification and Analysis System Specification Modelling: Components and Interfaces Integration of Techniques Simulation and Testing Assessment and Measurements Approach: Build in Safety/ Security from system inception Evaluate tradeoff between Safety and Security throughout the lifecycle Can use tradeoff analysis to evaluate/distinguish between design alternatives Safety and Security Tradeoffs System Safety Process Preliminary Hazard Analysis Monitor Residual Risk Accident and Risk Models Elimination, Mitigation, Control Certification System Security Process Preliminary Threat Assessment Certification Monitor Vulnerability Vulnerabilities and Attack Models Avoidance, Detection, Masking

5 Fundamental Research Questions  How do you quantify safety and security in a predictive manner?  What are the effects of other qualities on safety, security and their relationship Capacity, Efficiency, Environmental etc.  Can we model/quantify tradeoffs for the relationship between safety and security?

6 Thank You!