Alarm-based routing and path protection in survivable wavelength-routed all-optical mesh networks

We present what we believe to be a new fault-tolerant path-protection scheme, FTPP, for WDM mesh networks based on the alarming state of network nodes and links. Our extensive simulation results show that FTPP outperforms known path-protection schemes in terms of loss-of-service ratio and network throughput. The simulation tests used a wide range of values for the load intensity, the failure arrival rate, and the failure holding time. The effectiveness of our method has been demonstrated with the U. S. long-haul and the NSFNET topologies. We next extend the FTPP scheme to the differentiated services model and evaluate its connection blocking performance. We introduce a quality-of-service- (QoS-) enhanced FTPP (QEFTPP) routing and path-protection scheme in WDM networks. QEFTPP uses preemption to minimize the connection blocking percentage for high-priority traffic. Extensive simulation results show that QEFTPP can achieve a clear QoS differentiation among the traffic classes and at the same time provide good overall network performance. (c) 2005 Optical Society of America.