Path clustering: an approach to implement absolute QoS differentiation in optical burst-switched networks

Several schemes have been proposed recently in the literature for providing absolute QoS differentiation in OBS networks, such as early drop and wavelength grouping schemes. However, these schemes only provide loss guarantees at a per-hop level. In this paper, we propose a path clustering technique to implement these per-hop schemes over an entire network. The path clustering technique provides a solution to prioritizing the traffic based on hop-distances between source and destination pairs. We develop an analytical model for obtaining the optimal path clustering for a given network. By using the path clustering technique, we can improve the end-to-end loss performance of nonguaranteed traffic, and also provide absolute end-to-end loss probability of guaranteed traffic.