Connectivity Aware Protected Working Lightpath Envelope

Protected working lightpath envelope (PWLE) is a promising path-oriented protection strategy developed by us to provision survivable services for dynamic traffic. Partitioning the network capacity into a working layer and a protection layer by means of lightpath-protecting p-cycles, PWLE possesses the advantages of high capacity efficiency, avoidance of wavelength conversion, good blocking performance and guaranteed optical transmission quality. Nevertheless, the impact of network connectivity on the actual utilization of the working layer has been overlooked. Hence, we propose connectivity aware protected working lightpath envelope (CAPWLE) to augment the actual utilization of the working layer whilst retaining its high capacity efficiency. To fulfill the goal, we propose effective envelope, developed based on the maximum concurrent flow problem (MCFP), to evaluate the protection capability of lightpath-protecting p-cycles from a combined perspective of connectivity and volume. By virtue of effective envelope, CAPWLE is optimized by a mixed integer linear programming (MILP) model. Numerical results show that the actual utilization of the working layer is enhanced by CAPWLE under both dynamic stationary and non-stationary traffic patterns.