Comparison of SDH/SONET-WDM multi-layer networks with static and dynamic optical plane

In this paper, two principal SDH/SONET-WDM multi-layer network architectures are investigated covering the dynamics either only in the electrical layer or in both layers, respectively. In order to show benefits and drawbacks for the introduction of dynamics in the optical plane of today's backbone networks, we present a detailed performance evaluation based on simulation studies and compare both architectures for different total network capacities and grooming strategies. We also systematically analyze the traffic composition which until now has only rarely been investigated. We show that changes in the traffic pattern can be covered by a dynamic optical plane. Further, we figure out the timescale for switching operations in the optical layer which is at least two orders of magnitude below the connection's interarrival rate.