A High Performance Multicast Scheme Based on Virtual 2D Torus Topology

Wavelength division multiplexing (WDM) not only can increase the bandwidth of backbone transmission network significantly, but can also decrease the network cost and make the controlling and maintaining of transmission easy. A new algorithm, torus topology conversion algorithm (TTCA), is proposed in this paper. It is made up of three parts: (1) the conversion algorithm, developed from ring-tree-based RWA (RTRWA), is employed to change topologies from real networks into torus networks; (2) the earliest available channel (EAC) algorithm is utilized for wavelength assignment; and (3) time division multiplexing (TDM) is used for the scheduling algorithm to proceed on transmission of packets. The system performance of the TTCA is compared with both the RTRWA and Steiner minimal tree (SMT). The simulation results show that the call blocking probability of the TTCA can be reduced 10% to 20% more than that of the RTRWA and the channel utilization of the TTCA can be increased 40% to 50% more than that of the RTRWA.