In recent years, there has been considerable interest in applying Distributed Hash Tables (DHTs) to application-level multicast since DHTs have many advantages that are good for multicast applications: decentralization, scalability, fault tolerance, load balancing, and good routing performances. However, an effective bandwidth utilization method is required for DHT-based multicast systems because of a number of technical issues such as heterogeneous node capacity and dynamic membership. In this paper, the authors propose their BAM-Chord (i.e., Bandwidth Adaptive Multicast over Chord), a DHT-based multicast system that focuses on host heterogeneity, network scalability and effective bandwidth utilization. In the authors’ system, when a node joins into the system, it will find out an appropriate position (i.e., node identifier) on a BAM-Chord ring and create links to neighbor nodes based on node’s bandwidth capacity such that the multicast tree can be built efficiently and balanced. Therefore, their system can utilize bandwidth of every node efficiently to reduce the depth of the multicast tree, increase network scalability and take advantages of DHTs in maintaining the multicast tree.
Capacity of a class of multicast tree networks
