Measuring resilience in multi-carrier emergency and critical telecommunications systems

The ability to provide critical communications, particularly during disasters, is essential for national security and emergency preparedness (NS/EP). The authors present a quantitative study of the resilience of IP-based NS/EP services for the National Communications System (NCS). This analysis builds on a previous study of the survivability of a single carrierpsilas telecommunications network by extending it to a multi-carrier network. The authors quantify the differences in the ability to communicate depending on whether or not the carriers modify their internetwork routing policies to allow use of another carrier for transit by NS/EP traffic. The carrier network topologies used in the analysis are similar to major ISP backbones. The authors used IP-SURVIV, a Noblis network resiliency analysis tool, to analyze the throughput and connectivity of a multi-carrier network topology as network elements are disabled. Numerical results from random failure scenarios show that modifying internetwork routing policies to allow transit routing does improve network survivability, and should be considered for NS/EP traffic. This work also has broader application to resilience analysis of other critical communication systems on multi-carrier IP networks.