A cost-effective approach to optical packet/burst scheduling

Optical Burst and Packet Switching are being considered as the most promising paradigms to increase bandwidth efficiency in IP over DWDM networks. In both cases, due to statistical multiplexing, a scheduling policy is needed to solve contentions at the node level caused by more than one burst/packet directed to the same output channel. The scheduling may be performed in the wavelength, time and space domains, turning this problem into a choice of the best available resource in the different domains. Because of the very large bandwidth on the wavelength channels, the burst/packet arrival rate at the network nodes is very high and therefore the time available to take the scheduling decision is very limited. As a consequence, whatever scheduling policy is adopted, it must be implemented in an extremely effective way in terms of computational complexity. This paper is focused on a cost-effective solution to the scheduling problem, which is not based on typical search algorithms and whose complexity can be made almost independent of the dimension of the resource set to be searched.