Impairment-aware optical networking using cross-layer communication

We study strategies of relaxing physical layer constraints in flexible transparent optical transport networks through traffic engineering as well as through impairment-aware traffic management supported by crosslayer communication. We show that impairment-aware traffic management can effectively counteract inter-channel impairments on the physical layer and yield significant throughput gains. Using extensive Monte Carlo simulations, we find these throughput gains to be fairly independent of network topology and size. Based on analytical formulations for the performance gain resulting from impairment-aware networking we evaluate the dependence of the cost per bit on the applied traffic management method as well as on parameters such as the inter-channel impairment probability and the average network utilization.