Security Risk Management of Railway Transportation Systems

Railway operators and suppliers can count on well established techniques for safety assurance. However, the recent terrorist strikes have shown that security is also an important issue to be addressed by system engineers. While safety refers to the possible hazardous effect of the system upon the external environment, security studies the effect of the external environment upon the system, including natural as well as malicious threats. Terrorists are not the only adversaries: vandals, thieves and other perpetrators use to attack mass transit rail based system on a daily rate. Procedures and protection mechanisms are therefore needed for the safeguard of the infrastructure against external threats. This paper describes a systemic approach to the security risk management of railway infrastructures. The analysis addresses both methodological and technological means, showing that while a correspondence can be found between safety and security taxonomies, novel approaches are needed to cope with security specific issues.