The aggregation of multicast tree state information with delay-bandwidth constraints

In order to solve the scalability problem of QoS routing in large networks, hierarchical networks and hierarchical routing are proposed. There are tow key issues in Hierarchical Multicast Routing (HMR): one is Topology Aggregation (TA), and the other is Multicast Tree State Aggregation (MTSA). And the latter is discussed deeply in this paper. The main contributions of this paper include: Multicast Tree State Information (MTSI) with Delay-Bandwidth constraints is defined; Pseudo Tree Border Node (PTBN) mode is proposed to solve the aggregation of MTSI of a domain; at the same time, Layer Band Representation Points (LBRP) method is proposed to compress multi MTSI generated when aggregating MTSI using PTBN mode. Simulation results show that the number of MTSI not only stored in nodes but also broadcasted between nodes is largely reduced with PTBN aggregation mode in hierarchical networks.