Research And Design Of P2P Audio Education System In Armed Police Force Three-tier Network

Nurturing personnel to meet the requirements of the modernized war is a major task of the development of our army. Network education as a supplement of traditional education has played a more and more important role. In the last decades, Armed Police Force has made persistent efforts in this field which has made significant progress in the development of computer networks. Each company has been covered with LAN or WAN, which is the excellent infrastructure for online education.Therefore, we have designed an audio education system named "CAPF-Audio", the main purpose of which is to supply network education for the Armed Police Force. Our system contains four parts which are broadcast subsystem, receiver subsystem, management subsystem, and transmission subsystem. The transmission subsystem lies in the bottom of the system, and the main function of which is the focus of our research: to provide streaming media transmission services. The transmission system is different from the traditional transmission system based on central server. It utilizes P2P technology which has the superiority of performance, extension and fault-tolerance.The most crucial issue of P2P streaming media data transmission is how to form a tree structure which enables media transmitting among nodes, and avoid each client getting media data directly from servers. Based on such purpose, we have designed a protocol named RJALM(Random Join Application Layer Multicast Protocol) to control the organization of all the nodes. Data flows transmit among nodes in Ogg format. Nodes having received Ogg should control it before passing it to the decoder. Method to accomplish this process has also been designed.Finally, we have tested and deployed the designed system. Disadvantage and future improvement are also pointed out.