The Design And Implementation Of Center Server And Client Node In The CDN-P2P System

With the rapid development of Internet technology in recent years, the amount of Internet users grew explosively; the network congestion is increasingly becoming a bottleneck restricting the development of the Internet.CDN (Content Delivery Network) technology builds virtual platforms to reduce the occurrence of network congestion. However, the traditional CDN technology is based on C/S (Client/Server) computing model. Thus, when the amount of clients increased dramatically, the performance bottlenecks of the CDN-related servers are likely to occur. To improve service capacity, the ISPs need to deploy new distribution nodes continually, which lead to high cost. The emergence of P2P technology breaks the traditional C/S mode. In the P2P network, each node has equal status:each node can be either as a server or as a client.If we utilize P2P technology in the autonomy region, in general it will be able to provide users better service with lower bandwidth.In recent years, according to the complementary nature of the CDN and P2P networks, there occurs a combination technology of CDN and P2P However, The fast expansion of CDN-P2P hybrid system resulting in a series of problems. First, the load capacity of network resources is limited, users’ requirements to the request response time limit the scope of node sharing,so it can not really realize the file sharing between all P2P nodes; Second, with the CDN surrogate server and node traffic flow increases, the overloaded node’s request response time will increase, then consume the network resources excessively. Therefore, the establishment of a new model to deal with these issues is of great practical significance.This paper discusses the design and implementation of a CDN-P2P prototype system based on social attributes; it’s committed to the combination of CDN and P2P in the follow-up research and experiments, which laid a good foundation to the study of CDN-P2P hybrid system. In general, this prototype system has the following key points:First, it introduces the concept of nodes’ social attributes. Each node in the system can be treated as a natural person in the society, the attributes and preferences of user are node’s most import information. During system running, it can fully utilize the initiative of the node, and nodes can perceive each others’ social attributes automatically, so that the node can select a more reasonable search path to complete the search process quickly and efficiently.Second, it applies intelligent recommendation techniques to the CDN-P2P systems, through access to the file node has occurred or has demonstrated demands, demand analysis and demand forecasts, and provide recommendation service.Third, according to the changing of user’s social attributes, the system will update and evolute dynamically.Due to the users’ social attributes may change over time, the system needs to process these changes through some appropriate mechanisms with reasonable manners, thus updating the related information dynamically, then finish the evolution of the CDN-P2P system.The CDN-P2P system consists of three modules:central server, surrogate server and client nodes. This paper focuses on the design and implementation of central server and the client node, and mainly focuses on analysis of the selection of surrogate server, neighbor selection algorithm, the node status maintenance strategy, the resource search and downloads mechanism of the node. And finally, this paper analysis the system performance and provides improving direction.