New challenges in next-generation optical network planning

This work summarizes the main challenges that arise and need to be addressed in the core networks of the next generation, focusing on the excessive power-consumption, the heterogeneity of the traffic and the ever-growing need for transmission capacity. To achieve the “greening” of optical networks this paper proposes an energy-driven planning framework consisting of promising research efforts that aim to this target. In addition, we discuss the heterogeneous nature of the traffic that is rapidly transforming today's optical networks so as to accommodate mixed-line rates of 10 Gb/s, 40 Gb/s and 100 Gb/s. To this end the associated planning issues are visited. The unprecedented data traffic growth though, drives future optical networks even beyond 100 Gb/s. Optical Orthogonal Frequency Division Multiplexing (O-OFDM) is identified as a promising solution due to its intrinsic characteristics of spectrum efficiency and scalability, imposing though new networking constraints.