Collision-Aware Spectrum Assignment Scheme for Flexible Bandwidth Optical Networks

In order to increase the spectrum resource utilization, Flexible Bandwidth Optical Networks is developed to adaptively allocate an appropriately-sized optical bandwidth to an end-to-end optical path. In this paper, a novel collision-aware spectrum assignment scheme called Collision-aware Weight based Fit (CWF) has been proposed for Flexible Bandwidth Optical Networks. Based on the weight-based idea, we further develop two schemes, collision-aware unequal-weight based fit and collision-aware equal-weight based fit. The former assigns a different weight, which denotes the concurrent reservation probability, to each spectrum slot of the networks links. Yet the later adopts equal weight scheme. The destination can select spectrum slots with less collision probability according to the weight. Simulations are conducted to compare CWF with a few traditional schemes. Numerical results show that CWF performs better in blocking probability (BP) than the others under NSF network and has the same resource utilization.