Two-stage bandwidth-allocated algorithm for multi-subsystem-based VPON in metro-access optical network

In the metro-access optical network, a two-stage bandwidth-allocated algorithm is proposed for the multi-subsystem-based virtual passive optical network (VPON) that can achieve the syncretism of multiple systems such as time division multiplexing-PON, wavelength division multiplexing-PON and orthogonal frequency division multiplexing-PON. In this paper, the bandwidth is allocated in two stages. The first-stage allocation is designed to improve the admission probability of new VPONs by allocating bandwidth to all new VPONs followed by original VPONs. Meanwhile, to avoid the bandwidth being monopolized by the new VPONs, the bandwidth allocated to each VPON is no more than its guaranteed bandwidth. Therefore, the whole fairness can be guaranteed. The second-stage allocation is used to promote the bandwidth-utilized ratio by assigning the remaining bandwidth to VPONs whose demand is not fully met in the first stage. With the two-stage allocation, not only the admission probability can be improved, but also the bandwidth-utilized ratio can be promoted. MATLAB is used to evaluate the performance of proposed algorithm according to admission probability of new VPONs and bandwidth-utilized ratio.