Research On Concurrency Control And Load Balancing Scheduling Of Application Server Of VOD System

With the development of society, people want to choose their own preferred media resources conveniently, so video-on-demand technologies have emerged. However, it involves many advanced technologies and products. Interactive video-on-demand is still a complex system.Application server is an information release platform of VOD System as well as an interactive platform between the whole system and the users. All the media resources that Application server provides to the users are come from the back-office through communication messages. It is definitely a critical task to design and implement a fully functional, powerful and stable Application server. This paper has done some research and analysis about the VOD system based on HFC network and the Application Server, then designed and implemented the front-end module of Application Server using MVC ideas and Struts technique. This paper designs the message-communication module and detailed messages of Application Server using the SOAP protocol instead of complex COBRA interface using in VOD specification, implemented with multithreading technique. The messages design of Application server is divided into three functions including media-on-demand net-personal-video-recording and time-shifting-video. This design makes the Application Server flexible and easy to expand, greatly enhanced the stability and real-time quality of Application Server.There are large-scale media information and communication messages in VOD System, It is the key points how to enhance the performance of Application Server, making the Application server serves large-scale customers effectively and supports the video services in time and efficiently. This paper has resolved the concurrency problem of large-scale messages, designing a new type of concurrency control module, implemented with multithreading and database concurrency techniques. For the concurrent access of large-scale of set-top-box users, this paper has improved on the Weighted Least-Connection algorithm, and brings forward an algorithm fits for the Application Server through investigating many load-balancing algorithms. Therefore, the bottleneck of single server was solved, has improved the overall performance of Application Server.