Ten National Cyber Security Strategies: A Comparison -- Analysis of Dependencies in Critical Infrastructures -- Assurance and Trust Indicators to Evaluate Accuracy of On-line Risk in Critical Infrastructures -- An Innovative Approach to Emergency Management in Large Infrastructures -- Dynamic Evacuation Guidance as Safety Critical Application in Building Automation -- Defeating Node Based Attacks on SCADA Systems Using Probabilistic Packet Observation -- Sub-optimal Topological Protection Strategy from Advanced Malware -- The Insider Threat in Cloud Computing -- Interdependencies between Critical Infrastructures: Analyzing the Risk of Cascading Effects -- How to Perform Verification and Validation of Critical Infrastructure Modeling Tools -- Petri Net Modelling of Physical Vulnerability -- Investigating the Effect of Network Parameters on Coordinated Cyber Attacks Against a Simulated Power Plant -- The Role of the DNS in the Secure and Resilient Operation of CIs, the Energy System Example -- The Development of Warning, Advice and Reporting Points (WARPs) in UK National Infrastructure -- The Contribution of NEISAS to EP3R -- Policies to Improve Resilience against Major Industrial Accidents -- Fuzzy Input-Output Inoperability Model -- Dependencies Discovery and Analysis in Distributed Systems -- Protecting Critical Infrastructures from Stealth Attacks: A Closed-Loop Approach Involving Detection and Remediation -- Risk Assessment in Critical Infrastructure Security Modelling Based on Dependency Analysis -- Countermeasures Selection via Evidence Theory -- The Robustness of Assortativity.

This book constitutes revised selected papers from the 6th International Workshop on Critical Information Infrastructure Security, CRITIS 2011, held in Lucerne, Switzerland, in September 2011. The 16 full papers and 6 short papers presented in this volume were carefully reviewed and selected from 38 submissions. They deal with all areas of critical infrastructure protection research.