Design And Realization Of Grid-Based VOD Data Management System

Along with the development of VOD(Video-On-Demand)service, a series of problems, such as limited performance, finite memory space, lack of bandwidth and etc, have appeared in the traditional single-point server .As a result, the application scope has been limited greatly. Aiming at the situation, people start to adopt the method in which there are more than one distributed server providing the service together. Specifically, the methods for implementing the balance of the load on multi-servers include dynamic DNS, NAT , reverse agent, package filtrating and forwarding, Layer-4 switching, WWW locating and etc. For the restrictions between performance and price, all the fore-mentioned methods need to realize the dynamic management of files. Here, a powerful platform, which can manage a great number of dynamic, distributed and heterogeneous servers, is needed .Grid can supply this environment.At the beginning of the paper is a brief description of the background and the research project, the following part includes an introduction of the structure and the basic theory of the Grid technology and a detailed description of the typical structure for management of data and security(Globus). Then, the author makes an analysis and comparison among different solutions for load balance and give out a general design of Grid-based VOD system.Copy management is a very important part of the whole VOD...