中文摘要：

随着Internet技术的发展，开展网络流媒体服务仍然面临许多挑战性的技术问题，如实时控制和传输带宽需求等．本文提出一种分布式流媒体多播系统MBSS，通过一系列P2P算法，进行节点交换或者转移操作，可以及时修改维护多播树，可以更好地适应网络奈件的动态变化，有效地降低多播树代价．同时引入Knock—down技术使多播树具有更广泛的可扩展性．最后实验验证MBSS可以在视频流传榆上具有高效性和健壮性．

英文摘要：

With the development of Internet technology, there are still some challenging technology problems in network media service, such as real-time control and transmission bandwidth request and so on. This thesis has proposed a decentralized media stream multicast system called MBSS. Through using some P2P algorithms, the operations of swap and switch between nodes can modify the multicast tree to adapt the dynamic change of network conditions and reduce tree cost. At the same time, the Knock-down technology has been introduced to make the multicast tree has more expansibility. The experiment results have proved that MBSS can transmit the video stream efficiently and robustly.