On-line ICBR in a transparent GMPLS network: a reality check

Future optical transport networks are moving from static point-to-point connections towards dynamic wavelength-routed networks using all-optical, reconfigurable switching nodes. As a result, lightpaths are dynamically routed/switched entirely over the optical layer, eliminating current expensive electronic regenerators. However, the lack of OEO transponders (i.e., transparency) makes it necessary to consider the degrading effects of the physical transmission of optical signals accumulated along the path. An efficient strategy to face up this problem and to provide quality-enabled services is to take into account physical impairments during the path computation process (ICBR algorithm). In this paper we present a feasible solution which combines ICBR algorithms and the intelligence of a distributed GMPLS-based control plane to set up optical connections with the required QoS in the optical signal. Furthermore, experimental and analytical discussions are given for the assessment and validation of the proposed solution.