MTDS: A Multicast Tree Dynamic Switching Approach Based on Rate

Shared tree needs less state information stored in routers, but RP (rezendous point) can bring congestion easily. Source tree is in favor of balancing network traffic, but the cost of constructing the tree is relatively high in light traffic. A multicast tree dynamic switching approach based on rate, which takes advantages of both source and shared trees is proposed to promote multicast QoS in MPLS networks. At most time shared tree is adopted to optimize network resource assignments. When the total arriving rate at RP or some sources´ transmitting rates exceed respective maximum threshold, some high rate sources are switched to source tree to avoid the congestion at RP. If the rates decrease, they can be switched back to shared tree. The simulation results show that the packet loss rate and end-to-end delay is improved by deploying the switching approach in MPLS networks.