Network survivability against region failure

Communication networks are now facing more and more potential large scale region threats such as natural disaster and physical attack. Under such region failure scenarios, numerous network elements within a geographically correlated region may be simultaneously destroyed, resulting a dramatical compromise or even breakdown of overall network connectivity. In this paper, we study the network survivability against a random region failure, which is modeled as a circular cut residing on the network. For a network adopting the cost effective multiple path routing mechanism, we examine how the network throughput performance degrades with region failure under the region-disjoint and node-disjoint routing constraints. The corresponding traffic throughput optimization problem and linear programming formulation are also addressed. We further discuss the problem of upgrading network with the minimal cost when the link capacity is not sufficient to protect the network against region failure.