Application Layer Multicast-based Streaming Media Broadcast System

With the high-speed development and popularization of Internet technology, a lot of new applications appear. Many of them ,such as the network video frequency conference, the AODNOD,stock market quotation issue, the multimedia distance learning,the long-distance consultation needs high bandwidth multimedia. This type of application have caused the bandwidth consume suddenly. In order to alleviate the network bottleneck, the people proposed the multicast technology. At present, the service model of IP multicast and protocol have some deficiency which make it not be widely applied in the Internet. Under this condition, people change their work to research the new multicast framework—application layer multicast. Application layer multicast changes multicast function from routers to end-systems. End-system is to be used to realize all communicate functions of multicast group, for example, the construction of multicast tree, copy and distribute of data packet and so on. Many development facilities have proposed their own application layer multicast agreement.The paper studies most of the application layer multicast protocol. The mainly tasks include:(1) we studies the protocol of application layer multicast. The types of the protocol of application layer multicast are mainly include the "Mesh", the "Tree" and the especial logic framework. NICE is a protocol of application layer multicast base on the especial logic framework. It is can be use in the system of large-scale video living broadcast.(2) Then we improves NICE protocol based on analyzing application layer multicast protocol NICE .It mainly solved how to base the hierarchy select the leader of the group and how the node join the group at different bandwidth circumstance.(3) we analyze it by simulation which mainly carries with the NICE protocol. First, we simulate the max-delay ,average delay and the Stretch of the NICE and the improved NICE; then we simulate the RDP of improved NICE. The result has confirmed its good performance.(4) archetypal system is designed based on this new protocol. This system can provide service of real-time multimedia data transmission for the large-scale user. In this system, we realize the construction of multicast group, join and leave multicast group and the dispose of node failure. At last, we test the performance of this system .and the test result indicated that the prototype system has achieved the design requirements basically.