Research And Improvement On Peers-assisted CDN System

Nowdays, with the rapid development of the Internet, and increasing demand for information from the Internet, more and more Internet applications have emerged, such as content distribution network (CDN) and the peer to peer networks (P2P).Both CDN based and P2P based architectures have been proposed to distribute data. However, each kind of architecture has its own limitations. CDN has good management, but it needs to deploy many fixed CDN nodes around the world, and the deployment is expensive. On the other hand, P2P has a good scalability, it can solve the problem of server overload and resource bottlenecks. But the peers are free to join or leave, which lead to the instability of information on the network, Furthermore, P2P consumes a lot of network bandwidth.Therefore, some researchers proposed peers-assisted CDN system, which integrated CDN and P2P based content distribution system. The system takes advantage of P2P to help CDN distrubute datas, and improves the scalability of CDN.To solve the problem of consuming a lot of network bandwidth in P2P. Provider Portal for Applications (P4P) was proposed by the United States Yale University, it makes P2P Aplication obtain more accurate network information from ISP, thus reduce P2P traffic without lowering the performance of P2P, and even improve the network performance.In this paper, we improve the peers-assisted CDN system by taking advantage of P4P to the system, which allowed for more effective traffic control between applications and network providers. We propose a new dynamic network architecture, which is a new hybrid architecture integrating CDN, P2P and P4P technoligy. A content distribution node selection algorithm is given in full details. The new system reduces the traffic on network and lowers the cost of CDN server resources, without compromising the content quality delivered. Intensive experiments were conducted, which demonstrate that the new system significantly lowers the cost of CDN server resource and the algorithm reduces network cost, improves the performance of peers-assisted CDN.