Patent ID: 8886506

Claim:
A method comprising: receiving a network model including network elements, wherein a network element is one of a node, a link, a circuit, or a path, wherein at least one of the paths of the network elements has dynamic path restoration capability; receiving network simulation information that includes failure equivalence groups, a failure rate that indicates a rate of failure pertaining to each failure equivalence group, a repair rate that indicates a rate of repair pertaining to each failure equivalence group, a number of repair personnel assigned to each failure equivalence group, and a regeneration value indicating a number of regenerations to occur for each designated path during a network simulation, wherein a failure equivalence group includes one or more links belonging to one or more designated paths in the network model; executing the network simulation of the network model, wherein the executing comprises: biasing at least one of the failure rate or the repair rate for the failure equivalence groups; determining whether one of the one or more designated paths enters a failure state given a current biasing; unbiasing the at least one of the failure rate or the repair rate when it is determined that the one of the one or more designated paths enters the failure state; identifying when the failure equivalence groups return to an operative state; determining whether a regeneration of the one of the one or more designated paths is to be re-simulated based on the regeneration value associated with the one of the one or more designated paths; determining whether another one of the one or more designated paths is to be simulated when it is determined that the regeneration of the one of the one or more designated paths is not to be re-simulated; and ceasing an execution of the network simulation when it is determined that another one of the one or more designated paths does not exist; and calculating an average time of path unavailability for each designated path simulated based on the network simulation; and calculating path unavailability for each designated path simulated based on the network simulation.