Telecommunication technology has advanced to the point where direct failure of critical equipment is unlikely in modern central offices. However, increasing robustness of equipment is partly compromised by other trends: fewer trunks and more concentration of switching offices (fiber optics technology), more complex switching/signaling hierarchies and disparate hardness in the equipment and their host facilities. The result is that failure is now more likely to be caused by collateral hazards and failure of supporting lifelines, and as a result the impact of the failure on an urban system would be much greater than in the past. This project studies the effects of these trends. By applying Geographic Information Systems (GIS) technology to lifeline modeling, a range of assumptions concerning earthquake scenario, geological and collateral hazards, and interaction with supporting lifelines will be considered. The computer-based method developed to address the issues of concentration and interactions, including the use of GIS as a platform for combining complex topologies of interacting lifelines with hazards, will be used in network design, emergency planning and preventive risk management. The project will advance engineering capabilities to determine the lifeline interaction effects under seismic hazards through a GIS based network design system.
