Novel Impairment-aware Traffic Engineering in All-Optical Networks

We propose a novel traffic engineering (TE) technique that can readily handle impairments so as to satisfy quality-of-signal (QoS) requirements in all-optical networks. The existence of impairment limits the maximum transmission distance of optical signals given the need to satisfy QoS requirements. The problem is that impairment-aware route computation must consider many parameters and so is rather complicated. We, therefore, propose the new TE-constraint of "logical distance" which covers several impairment factors converted into distance. It reflects the degree of impairment created by external conditions, and a transmission distance constraint can be checked easily by summing up each element's distance. Logical distance makes it simple and effective to judge whether a computed route satisfies the desired QoS or not. We confirm the feasibility of our proposal by developing a TE system for a real optical network.