We are now in a new era of Supernetworks as the  Biggest Blackout  in United States history has fundamentally and dramatically illustrated. We as human decision-makers whether scientists, engineers, managers, and government officials can no longer  study and manage individual network systems such as energy, transportation, and telecommunication networks independently. Moreover, it is insufficient to simply address the physical infrastructure in the form of nodes and links in terms of network design since it is ultimately the behavior of the individuals  and the decision-makers on these systems that affect the flows, the congestion, the associated costs, the throughput, and their survivability

Indeed, the biggest blackout in US history involved not only the severance of physical links in the form of transmission lines but through the coupling of human involvement in the management of the power grids resulted in tremendous losses for some whereas others in neighboring regions and communities were relatively unaffected and, in some instance, even gained, due to the availability of power, fuel, and other products. The loss of power affected not only telecommunication networks in the form of cell phones and even email servers but propagated through transportation networks resulting in the  shutdown of airlines, rail lines, and tremendous road congestion in the form of both vehicular as well as pedestrian in New York City. Mail service was affected nationally and water distribution collapsed in Cleveland. Financial networks in the form of ATMs stopped functioning.

The topic of networks and network management is not new and dates to ancient times with such classical examples including the publicly provided Roman road network and the time of day chariot policy, whereby chariots were banned from the ancient city of Rome during particular times of the day. The topic of networks as a subject of scientific inquiry originates in the paper by Euler in 1736, which is credited with being the earliest paper on graph theory, where a graph in this context is meant an abstract or mathematical representation of a system by its depiction in terms of vertices (nodes) and edges (or arcs) connecting various pairs of vertices. Interestingly, not long thereafter, Quesnay in 1758, in his Tableau Economique, conceptualized the circular flow of an economy as a network. Monge, who had worked under Napoleon Bonaparte in providing the infrastructure support for his army, published what is probably the first paper on the transportation network model in 1781.

What is new about the network systems today is that they are interconnected in the form of  Supernetworks. Decision-making on networks can take on many forms; it can be centralized or decentralized; it can be cooperative or competitive. Moreover,  supernetworks are of massive dimensions, are increasingly characterized by congestion, and have effects far afield.

The complexity, however, may be captured and harnessed through novel management tools. Indeed, today, it is possible, through advances in scientific models, theories, and computational tools to predict optimal routes on networks from different origins to destinations both from a system-optimized perspective, in which there is a central controller of the network flows, as well as from a user-optimized one, in which users of the network select their optimal routes in what may be viewed as a selfish manner. We know now that in both urban transportation networks as well as in the case of the Internet the addition of a new link may actually make everyone worse off! So careful management is essential.

It is imperative that knowledge surrounding networks and decision-making on them gets disseminated in a timely manner. There is no time for reinventing the wheel. For further background on network topics and their interrelationships, see the Virtual Center for Supernetworks; http://supernet.som.umass.edu
 

Professor Anna Nagurney is the author of 8 books on network topics including (with J. Dong) the book, Supernetworks: Decision-Making for the Information Age (2002), and is the editor of Innovations in Economic and Financial Networks (in press - October 2003).
 

Last update: August 20, 2003