QoS differentiation in optical packet-switched networks

This paper deals with the problem of service differentiation in an optical packet-switched backbone. A QoS-aware network function based on different routing and contention resolution strategies for different classes of service is proposed and analyzed. Contention resolution is performed by using both wavelength and time domains and QoS differentiation at the single node level is achieved by resource partitioning in the wavelength domain. This technique is combined with multi-path routing at the network level. The paper, analyzing different network topologies under different traffic assumptions, shows that the proposed strategies guarantee a good performance differentiation between two levels of traffic priority. Finally, a network design procedure is also illustrated and discussed.