Protection by diversity in elastic optical networks subject to single link failure

Among the multipath protection schemes found in the literature, the Partitioning Dedicated Path Protection — PDPP proposes to divide the total transmission rate required by the connection in equal parts, and then proceed the transmission of each part using multiple disjoint paths. Nevertheless, it is also possible to partition the transmission rate unequally among paths, enabling benefits to network performance. This article proposes a mixed-integer linear programming (MILP) formulation to find an optimized unequally partitioning of connections’ transmission rate among multiple disjoint paths, in order to provide dedicated protection and reduction in maximum number of slots on network and average bandwidth squeezing. The solution is analysed over a number of realistic networks, showing that the proposed formulation significantly reduces the spectral usage compared to traditional protection mechanisms and reduces the amount of squeezing required compared to the former PDPP approach.