Multi-objective evolutionary algorithm for the design of resilient OTN over DWDM networks

Abstract

Optical Transport Networks (OTN) arrived in the communications market bringing economic and operational benefits of virtualization. This technology works as a superior layer to the DWDM (Dense Wavelength Division Multiplexing) network, allowing more efficient resource usage. OTN approach decouples customers from DWDM interfaces, ensuring that optical links work more efficiently. This concept is carried out at OTN switches, allowing traffic to be aggregated at intermediate nodes and directed to routes that are being underutilized. Planning OTN over optical networks is a complex problem involving a new equipment structure and logical architecture. This problem has arisen due to academia and industry’s interest in developing planning heuristics to reduce the cost of the network. This paper proposes an algorithm to perform OTN network planning to meet the services and their survivability requirements such as restoration and/or protection with the goal of reducing the network cost in terms of the number of OTN interfaces. We propose to use a multi-objective evolutionary algorithm to seek a solution that optimizes the project considering two conflicting decision variables: the number of used OTN interfaces and the average number of restored paths in case of double-link failures. The experiments showed that the proposed solution obtained fewer allocated interfaces than previous heuristic algorithms found in the literature.