The Design And Implementation Of Cdn System Based On P2p Technology

With the development of computer technology, network technology, multimedia technology and other related technology, video on demand (VOD) applications has become one of the main internet applications. The occupying of VOD service on system resources, network bandwidth is high. Users continued to occupy the resources of the system, thus VOD business can’t provide much number of concurrent users. Internet network environment is complex, and the service experience of inter-regional VOD system is difficult to be guaranteed. With the times past by, the online multi-media broadcast system has become a real-time platform of information distribution of some news liveshow. The user number of concurrent access to the media broadcast network is incalculable. Such as:2006 Super Girl webcast, the livecast system just paralyzed in 30 minutes. How to build a fully functional, operational, easily managed VOD service platform is a real problem. Beijing Unicom streaming media platform is CDN architecture based media service system.It already has been in construction for many years. And it is facing the problem with big investment and poor user experience. The urgent problem to solute is, how to upgrade the existing CDN systems, and support large number of concurrent livecast user.After analysing the requirements of the Beijing Unicom streaming media platform, we suggest to upgrade the CDN architecture with combining with the original CDN system architecture and equipment, changing the original guide model of Level-4 devices, intergrating into the software CDN system, arranging software cache devices in various regions of nodes, and enhancing the CDN concurrency. There are two technical, routes in large number of concurrent livecast user:Multicast and P2P technology. Taking multicast mode into the Internet environment requires a major adjustment of network devices. Because some older network devices do not support multicast setting, also we need to release the radio set, may cause a greater impact to the backbone network. So we can’t use this way. P2P broadcast technology use Peer To Peer network technology, through the direct exchange between the client computers to share resources and services, take a small amount of application of system resources. Since the data exchange i s done between the client, assuming there is no network resources bottleneck, thus P2P number of concurrent users is unlimited. However, uncontrolled P2P technology will result in a large number of Internet network resources waste. Therefore, we propose a technique based on P2P CDN system architecture, that is a regional node in the P2P autonomy within the field, both to improve the user experience results, nor will it cause too much pressure on the backbone network. With the designing and implementation of the project, the user experience of the CDN live cast has been improved, the pressure on the backbone network bandwidth has been reduced. With the effective management and utilization of P2P, it has meet the requirement of Beijing Unicom in integrating of these two technology.