Critical infrastructure is generally defined as those systems and assets, whose destruction or incapacity would cause catastrophic health effects or mass casualties, impair government abilities to perform essential missions or ensure the public's health and safety, undermine State and local government capacities to maintain order and deliver minimum essential public services, damage the private sector's capability to ensure the orderly functioning of the economy.
Critical infrastructure therefore includes Information & Communication Technology (Data Communications, Fixed Voice Communications, Mail, Public Information, Wireless Communications), Energy (Electricity, Natural Gas, Petroleum), Water (Mains Water, Sewage), Transport Nodes and Networks (Aviation, Marine, Rail and Road), Finance (Asset Management, Financial Facilities, Investment Banking, Markets, Retail Banking), Emergency Services (Police, Fire & Ambulance) and Health (Health Care, Public Health).
As our society becomes more mobile and interconnected, the need to protect 21st-century critical infrastructure has never been greater. These infrastructures have grown complex and interconnected, meaning that a disruption in one may lead to disruptions in others. The principal cause of critical infrastructure fragility today can be attributed to complexity and connectivity. In particular, the national security community has been concerned for sometime about the vulnerability of critical infrastructure to natural, physical and cyber attack.
Because the private sector owns approximately 85 percent of the nation's critical infrastructure, it is vital that the private sector has sufficient capability in place to secure and protect these assets.