Supporting adaptive QoS for multiple classes of service in DWDM networks

In a dense wavelength division multiplexed (DWDM) network, a connection must be established along a route using a common wavelength on all links along the route. This constraint may be removed by introducing wavelength converters, which take the data modulated on an input wavelength, and transfer it to a different wavelength. Wavelength converters improve network blocking performance as well as QoS management. In this paper we present a scheme for a dynamic resource management using heterogeneous traffic descriptors. A simple C-priority class scheme to support basic QoS at the DWDM layer in optical networks is presented. Unlike existing approaches which depend on buffers management and scheduling algorithms, our scheme does not require any buffers in the DWDM layer in order to ensure the header packet computing and differentiate the classes. The proposed scheme assigns different delayed times to each class in order to isolate higher priority classes from lower priority classes. Finally, we develop a traffic model and an allocation wavelength model, and analyze the blocking probability of each class.