P2p Coverage Of The Network Application Layer Multicast Technology

With the rapid development of computer network communication technology, there will be more and more network-based applications. New applications with multimedia features have emerged, such as video on demand, computer supported cooperative work, and television & telephone conferences. These new multimedia applications have the characteristics of large volumes of data, long duration, high requirement of delay and so on. If using the traditional mechanism of unicast and the broadcast technology to solve these problems, it will increase the transmission burden on the network and cause great waste of the network bandwidth. So many researchers have proposed the concept of multicast.Multicast is a point to multipoint (multi-multipoint) communications mode, that is, a number of recipients receive the same information from a multicast source. Compared with the traditional unicast and broadcast mechanism, multicast will reduce the redundant packet replication rate, use the network bandwidth effectively, improve the utilization of network resources, and avoid "broadcast storm". Multicast architecture is divided into IP multicast and application-layer multicast. IP multicast is the multicast on network layer; it mainly achieves the multicast technology through the router. Because IP multicast has many shortcomings, many researchers begin to reflect on the IP multicast architecture itself, and have proposed the new idea of application-layer multicast. Application-layer multicast achieves the multicast forwarding function in the end system, and they do not change the network architecture, it can be used to achieve efficient business content distribution network quickly. At the same time, P2P technology is developing rapidly. In P2P network, every host is not only a client but also a server on the network, and the network can constitute an overlay network. P2P technology facilitates application-layer multicast, and plays an important role in promoting the application-layer multicast technology research.In this thesis, we mainly study the application-layer multicast technology which is based on P2P overlay network. This thesis is divided into five chapters:the first chapter introduces the research background, IP multicast technology classification and problem, then we highlights the relevant knowledge of application-layer multicast, including the basic ideas, strengths and weaknesses, classification and evaluation criteria. The second chapter introduces the basic concepts and classification of the P2P, the research status of the application-layer multicast technology, and the several application-layer multicast protocols. The third chapter proposes a novel scheme named LCcast; we illustrate the overlay network, node joining, node existence and failure, and the data transmission. Moreover we give the node join algorithm description, the data transmission algorithm description and the corresponding code. Finally at this chapter, we give the simulation results. The fourth chapter proposes the novel model called H-Ring; we describe the overlay network topology, node joining, node leaving, node failure, and data transmission in detail. Furthermore we give the description of the data transmission algorithm and simulation experimental analysis. The fifth chapter summarizes the thesis and gives the solution in the next step.