Optimization And Implementation Of Peer-to-peer Video-on-demand System

Today the P2P video-on-demand technology is a research focusing on multimedia communications area. This research focuses on optimizing of the P2P network structure and resources searching algorithm, data storage structure and the buffer replacement algorithm, utilization of the client's buffer, enhance the data read and write performance and scalability, optimizing P2P communication protocols. The paper has realized a high-performance P2P VOD system which can be applied to a complex network environment.Via analyzing the differences between in VOD systems and video broadcast system, the author pointed out that complex access could result in difficult of data sharing for P2P VOD system. How the buffer to be distributed and how the buffer to be replaced in P2P VOD is very important. Then the author gives the key technologies used in the system, such as P2P network architecture and resources searching strategy, video encoding and playback technology, data indexing and buffering strategy, buffer replacement algorithm, and NAT hole punching technology. The author gives the system framework and implementation solution by analysis the functional in VOD system. The system is divided into 7 subsystems, includes Identification Management Server, Directory Server, Publisher Source Server, Publisher Mirror Server, Client, Database Server, Admin Server. Then gives what functions each subsystem has and how they are designed. The paper also details of the data structures and related algorithms in the system, focusing on the source file index structure, server-side buffer structure and replacement algorithm, the client buffer block structure, the client buffer replacement algorithm, mapping between P2P nodes and buffer data. The author also details the main communication protocol of the system. The log data analysis by running real system shows that the server resource consumption, the client's buffer distribution and operation effect, experimental results show that the system is an efficient P2P VOD system. It can support multiple more concurrent users than the unicast system with the same hardware resources. That has great value.In short, this paper make innovative work on network architecture for large-scale P2P VOD system, searching and scheduling algorithms, video source storage indexing methods, file block buffer structure, the buffer replacement algorithm, the server distributed architecture. It gives a series of innovative solutions, implementation strategies and methods. Through the work of a large number of experiments, the value of theory and practice of this paper has been proved. This study on the optimization of VOD system architecture and client buffer utilization, improve system resource utilization efficiency and reduce response time for users on VOD, improve the system capacity has a greater contribution. With the passage of time and development of technology, the practical significance of this paper will be reflected and tested in the future.