Performance Analysis of Prioritized Bu er Management in Photonic Packet Switches for Di Serv Assured Forwarding

We investigated the photonic packet switch architecture that enables a high node throughput and provides priority services. Previously, we proposed PBSO (partial buffer sharing with overwriting) method that enables prioritized buffer management to control an optical buffer [1]. The PBSO method is based on a single queue and its complexity is O p , where p is the number of priority classes. PBSO can be used to provide different levels of drop precedence in DiffServ (Differentiated Services) Assured Forwarding. In this paper, we propose an analytical method of PBSO where p . We assess the accuracy of the analytic method. We show that PBSO improves the packet loss probability in each priority class more than the existing PBS (partial buffer sharing) does, and that it can be used for prioritized buffer management of an optical buffer. PBSO is especially effective when the arrival rate of higher priority class packets is much lower than that of lower priority class packets. In this case, PBSO dramatically improves the performance of higher priority class packets while the degradation in the performance of lower priority class packets is small. In PBSO, a larger number of higher priority class packets can be accepted at a given packet loss probability than in PBS or non-priority method.