Reliable Multicast Data Delivery System Of Key Technologies And Systems To Achieve

In today's society, information exchange and continual education are becoming the principal development issues. In China, the rural villagers who living far from large city have the active demands of bulk information and various education resources to narrow the current gap between the rural places and cities. And these information demands may be included in multimedia information with mass data.After a deep study on the status of the transmission channel in China, we put forward the point that the method to utilize the existing wired television network for a reliable multicast data transmission system has the capability to meet the mentioned challenge, and is a reasonable and applicable means for approaches too.a number of comparisons and analysis on different reliable multicast data transmission protocols have been carried out. Considering the one-way characteristic of the Chinese CATV network, the ALC is regarded as the best suitable multicast data transmission protocol for China.Based on the study of a number of key techniques in ALC protocol, the main achievements of this thesis are to develop three key feasible and effective technique solutions, including multi-channel data transmission organization, sending speed control and congestion control schemes.On data sending strategy, this paper this paper introduce a method for sending Object orderly, and sending Symbol in Object disorderly. This method can decrease memory usage and promote receiving efficiency.On the mechanism of speed control, the paper presented a proper speed control method for a big amount of thin flow sessions.On the respect of congestion control, at the same time of making some improvement on FLID, a method of controlling total receiving flow of host adjusting to its performance is put forward in this paper.The thesis also describes the implementation of the reliable multicast data transmission system with the adaptation of ALC and the above three key schemes. This system is applied in ZJU remote education broadcast-television-online project, one of the Zhejiang province 5112 projects, and Zhejiang rural technology information project, one of Zhejiang province's major technology development projects.