Research And Experiments Of Large Scale P2P-CDN System

Nowadays, a new digital service has been gradually introduced into our daily life, and it begins to overthrow the traditional passive and one-way mode of watching TV by offering customers an active and interactive mode. Such service is called IPTV. IPTV is usually named Network Television, through IPTV, the customers will be provided with services like on-demand videos and watch-back. Currently there are two ways to enjoy IPTV:One can either install client software on his/her personal computer or add a TV-top box and link it to the internet. The way of adding a TV-top box is of higher customer serving performance and stronger stability. Moreover televisions have already been much more popular than computers. So the customers are more willing to achieve it with TV-top boxes. Since the TV-top box method will cost more in technologies, this paper is dedicated in discussing and researching on this architecture.Unlike the traditional way of watching TV, IPTV uses Ethernet as its transport medium rather than the traditional broadcast and television network. This requires ISPs, media providers and network facility providers to work much tighter than ever before to construct the IPTV system. To assure the customers get as good quality of service when using IPTV as they get from traditional TV service, ISPs should provide customers with high speed broadband and facility providers need to optimize their facility configuration to low the cost of IPTV service. Based on the facts that number of customers of IPTV is quite large, customers are mostly discretely scattered and that requirement for QoS is high, facility providers and ISPs usually use CDN system as the practical percept when building IPTV system. Thanks to the features, like leveled structure, load balance and edge-node content pushing, of CDN system, it serves IPTV service very well.But as IPTV keeps being promoted, the number of customers keeps expanding and that more new related service become available, current CDN system has to face the problems such as lacking in scalability and high cost to upgrade. So we need to improve current CDN system from the aspect of technologies to make it adaptable with the growth of IPTV service. Currently one of the solutions for such problem is to form a new P2P-CDN system by combining P2P technology with existing CDN system so as to solve the disadvantage of CDN system with extraordinary scalability of P2P technology. However, though the concept of P2P-CDN system has been widely accepted and has been utilized in business and is working well, most current researches about P2P-CDN system are focused on its theoretic description and evaluation of such existing systems rather than fundamental and quantificational analysis. So this paper builds virtual models with computers of CDN system and different P2P network structures. And with massive and precise simulation experiments, we combine CDN system with different P2P architectures and simulate. Then we perform quantificational analysis of statistical simulation data and try to find an optimized configuration for P2P-CDN system by analyzing the data of related performance parameters. With this serial of analysis, we could offer the future constructions of P2P-CDN system more persuasive advice in the aspects of theory and practical data.