Reduction of Crosstalk in WDM Networks with Optional FEC Coding

Y. Pointurier, M. Brandt-Pearce (USA), and B. Xu (PRC)


Optical Network Multi-layer Design, Routing and Wavelength Assignment, Interchannel Crosstalk, Node Crosstalk, QoS, Fairness.


In all-optical WDM networks, signals propagate over very long physical lightpaths without regeneration. Signals are subject to well-known physical impairments which are sen sitive not only to the network topology, such as amplifier noise, but also to new impairments which vary with the network utilization. These impairments are interchannel crosstalk due to nonlinear signals combinations within the fiber links, and node crosstalk due to optical leaks inside the network nodes. As a result, calls in all-optical networks may be rejected because they do not meet a minimal QoS constraint which has to be enforced to ensure nearly error free network operation. Recently, Routing and Wavelength Assignment (RWA) algorithms that account for network physical impairments have been developed. Some of them use FEC coding to trade, when needed, bandwidth utiliza tion against higher QoS. RWA with optional FEC coding has been studied only for noise-limited networks. We show how RWA algorithms with optional FEC coding can be em ployed to reduce both static and dynamic physical impair ments. We show that RWA algorithms with optional FEC coding are efficient to decrease call blocking probabilities, and also improve resource allocation fairness, in the con text of a realistic continental-sized network.

Important Links:

Go Back