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With the continued progress and development of computer technology, Internet technology, and multimedia technology, network based video streaming service has been widely used. This network services including VOD, live video, IPTV and a variety of value-added services such as: large amount of media data, real-time, high bandwidth resource requirements for storage and networking equipment, as well as the server. The need for this new type of network service, resulting in a P2P-based media distribution network (Media Delivery Network based on P2P networks, referred to as P2P-MDN), this network architecture effectively combines Content Distribution Network Content Delivery Network (CDN) peer-to-peer network (Peer to Peer, referred to as P2P) the advantages of both networks. This network focused on the specific methods to improve system performance, such as node selection algorithm, replica placement strategy, content routing mechanisms, the lack of analysis and performance assessment of the effectiveness of the entire system. This paper first describes the overall architecture and the key technology of P2P-MDN), and then through the modeling of P2P-MDN carrying capacity and effectiveness of the network, while analysis of the relationship between the network performance and configuration parameters, This is a good guide to build and optimize the network. The main work of this article includes the following two aspects: 1. System analysis of the carrying amount of fixed parameter configuration and policy deployment: system, the system is capable of carrying the maximum throughput. In this paper, first established the P2P-MDN model based on linear programming, considering the the PN node capacity, PN between nodes, bandwidth, disk I / O bandwidth limiting factor in the model, it is a good the P2P-MDN performance evaluation model, then the P2P-MDN model by the method of data instances, analysis system uses different parameters and policy configuration, system throughput, and to find the relationship between them. Main PN storage capacity of the local hit rate here, and PN storage capacity, PN bandwidth and storage strategy on the throughput of the system. Analysis conclusion that the main configuration parameters of the system, such as the PN node capacity, PN node bandwidth, disk I / O bandwidth in different combinations of configurations, are likely to become the main constraints of the system, to become the bottleneck of the system performance increase. Therefore should be reasonable combination of system parameters, so that the system under the premise of limited resources and costs, maximize system resource utilization. 2. Analysis of the effectiveness of the system: In order to analyze the effectiveness of the architecture of the P2P-MDN, this paper established a model based on the M/M/1 queuing P2P-MDN, the average response time for user requests can be solved through the model, the estimated system performance good guide. Queuing based on the model of P2P-MDN, the average response time of user-system performance indicators, analyze the impact of the network in the introduction of P2P technology on system performance, results showed that the introduction of P2P technology in the traditional CDN level is not must be able to reduce the response time, only if they meet certain conditions, the introduction of P2P technology can reduce the user requests a delay to improve the user experience. Also analyzed the impact of the hit ratio of a local file on the system performance, as well as in the case of a certain capacity of the entire service of the system, the optimal deployment of the system parameters, and given an optimum configuration parameters, in this configuration can be made the minimum of the average response time of the user request.
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