Vulnerabilities and protection of interconnected critical infrastructure networks

¶ … Infrastructure Protection

Utilities such as water, natural gas, and electricity are considered lifelines for the United States and its economy. Are they vulnerable to terrorist attacks or natural disasters? How can they be protected and secured?

Importance of Infrastructure

Critical infrastructures, such as telecommunications, energy, banking and finance, transportation, water systems and emergency services are the foundations of modern society. They support and maintain the economic operation and activities of our communities and help to maintain the functions, security, safety and stability of society. Our economy, national defence, and quality of life are increasingly reliant upon certain critical infrastructures.

As technology advances, more and more critical infrastructures become increasingly interconnected. More specifically, there is a heavy dependence on critical infrastructures at multiple levels within the supply chain of any good or service (Haimes, 2005). Any disruptions in the supply chain may cause profound cascading effect to other critical infrastructures. A malicious attack, natural disaster, or simply increasing stress on already congested infrastructure could have dramatic impact.

Infrastructure Networks

The definition of infrastructure networks has evolved considerably, especially since the attacks of September 11, 2011. A comprehensive reference of this evolution is given by Moteff and Parfomak (John, 2005). The growing interdependence and associated vulnerabilities in networked systems has been highlighted in public law. The U.S.A. PATRIOT Act states:

Private business, government, and the national security apparatus increasingly depend on an interdependent network of critical physical and information infrastructures, including telecommunication, energy, financial services, water, and transportation sectors (Federal Highway Administration and Cambridge Systematic, 2005).

Although often ignored in analysing other networks, social networks usually play a key role in the operation and development of other types of networks. For example, in infrastructure networks, humans interact with these networks as managers, operators, and users. While humans play an important role in the efficiency and security of infrastructure networks, they are also "the most susceptible to failure and the most adaptable in the management of recovery," (Massoud, 2002) therefore, "we will not be able to attack the technical and human portions of the network separately...destroying terrorists network requires combinations of physical and social approaches" (Robert, 2005). The effectiveness and response of a network during and after an attack are determined by humans. For example, "the effectiveness of attacking a power grid may depend on how the operators respond to limit the damage or redirect power" (Robert, 2005).

Vulnerabilities associated with the production of electricity are of special interest because of its integral role in economy, national defence, and quality of life. "The inoperability caused by wilful attacks, accidental events, or natural causes can set off a complex chain of cascading impacts on other interconnected systems, and the ripple effect that could occur from a disruption in electricity production alone is profound. The desire for higher levels of national security and the survivability of the economy demands better assessment and management of our critical infrastructures.

Through interdependencies, the disruption of one infrastructure system can cascade into other infrastructure systems. That is, the loss of expected services of one infrastructure system could be the result of disruptions within another. For example, in power outage that occurred in the western United States in 1996, a power line short-circuited after it sagged onto a tree, and then cascaded into a power-grid collapse that almost led to the collapse of telecommunications networks. (Robinson, 1998)

Strategy for Protection

Our society is increasingly reliant upon certain critical infrastructures. Thus highly interconnected infrastructures increase the chance of catastrophic impacts from a disruption in one part of the supply chain.

Because of the heavy reliance on infrastructures as part of our way of life, their protection is vital. Strategic guidance/objectives for critical infrastructure protection are provided in a series of National Strategy documents, congressional acts, presidential directives, and DoD directives. Government has introduced plans to protect infrastructure, however, there are insufficient resources and funding to fully protect all the nation's infrastructures. In addition, much of this infrastructure is in private hands. Even if resources were greatly increased, it would be fiscally and physically impossible to protect everything, particularly while an open society in maintained.

Therefore, continued analysis is needed to investigate how to optimally invest in infrastructure protection, i.e., how to obtain the most protection with limited resources. This is especially important in light of both potential terrorist attacks and risk of natural disasters.

The severe consequences caused by natural disasters and malicious attacks in the past years showed the importance of understanding the interdependencies among infrastructures in order to take preventive actions and to make post event responses. There is need to identify and understand interdependency related problems among infrastructures to prevent and manage interdependency related risks.