Research On Overlay Multicast Protocols

With the development of information technology, such as multimedia group applications, people hope Internet could support multicast communications. The general approach of overlay multicast is to have end systems perform all multicast communications instead of IP routers. It requires no change to the existing Internet infrastructure, thus has become an increasingly popular alternative to IP multicast.In this thesis, overlay multicast protocols and algorithms. We first define a general overlay multicast network model, and discuss the recent overlay multicast protocols and algorithms. Based on the work above, our research is performed in two aspects: proxy-based overlay multicast algorithms and dynamic nodes based overlay multicast protocols.In the study of proxy-based overlay multicast algorithms, a new heuristic spanning algorithm called balanced and robust spanning tree algorithm (BRST) is proposed. Using BRST algorithm, a multi-constrained minimal cost tree is constructed incrementally, which achieves a desirable trade-off between the delay performance and the network resource utility, and display more robustness.In the study of dynamic node based overlay multicast protocols, a new fast and QoS overlay multicast protocol (FQMP) is proposed. FQMP provide efficient algorithms for node' joining and optimizing procedures. FQMP achieves good QoS for members and reduces the network resource cost as well as protocol control cost.The research results of this thesis could provide new theoretical method to study of overly multicast. It can also be applied to practical overlay multicast systems.