The Design And Implement Of A Large-Scale System Based On Peercast

Recently, streaming media has gradually become more and more popular. However, unlike conventional Internet applications, the streaming media has the traits of high bandwidth requirement and long duration, the resources of server, such as bandwidth, process ability and CPU usage, will be consumed quickly, which becomes the bottleneck of the whole system. In order to solve the problem, more and more kinds of live streaming system, which are based on P2P transmission mode, appear. Peercast is one of the prototypes for such applications.This paper mainly focuses on the introducion of P2P media streaming technology and streaming media technology and application layer multicast technology。It also gives a detailed analysis on the Application Layer Multicast tree structure that Peercast system。The content includes the system structure of Peercast, network structure of Peercast.the mainly process, PCP protocol's internal mechanism, and the principle of each module.The problem that the player can't play the channel after the node reconnects the system has been found after the test. In order to solve this problem, we read the source code of the Peercast and analysis the Peercast system's buffer mechanism, modify the code.at last we solve the problem.In order to make the Peercast system can support the large-scale application. We add a Super-Node layer into the original system. The Super-Node and the nodes which connect to the Super-Node directly or indirectly form a domain. Nodes in the same domain belong to the same region, such as in a school or company. Each Super-Node maintains a domain. The nodes in the main get data from the super-node.we re-design the software of the YP, the super-node and the tracker. In order to keep the encapsulation of the domain, the play process and heartbeat detection mechanism are improved. Finally, we test the improved system.