Risk reduction based survivable WDM network design

This paper presents an investment strategy to reduce the risk associated with failures in wavelength division multiplexing (WDM) optical networks. The investment strategy determines how to allocate a fixed budget for implementing survivability techniques in different parts of the network such that the expected loss of traffic (ELT) is minimized. Two survivability schemes are considered in this paper: dedicated link protection and dedicated path protection. Two analytical techniques for evaluating network unavailability and ELT are presented in this paper: a fault tree analysis and an event tree. Based on the event tree approach, we propose a novel mixed integer linear programming (MILP) formulation for the investment strategy problem. Numerical results illustrating the investment strategy for both link and path protection are presented and discussed