中文摘要：

针对现有P2P文件共享系统采用并发多连接的文件传输方式，过分占用网络带宽资源，导致其它传统互联网业务性能低下的问题，提出了一种P2P文件共享系统汇聚拥塞控制机制（ACCM）。ACCM采用应用层网络测量技术感知节点接入网链路拥塞状况，依据网络拥塞状况动态地调整P2P文件共享系统并发文件传输连接窗口，在最大化网络带宽利用率的基础上实现对传统互联网应用的友好性。网络实验结果表明，在网络拥塞发生时，ACCM能够促使P2P文件共享系统并发连接窗口主动退避，实现和传统互联网应用的和平共处；在网络空闲时，ACCM能够促使P2P文件共享系统扩大并发连接窗口，提高网络带宽资源的利用率。

英文摘要：

In consideration of existing P2P file sharing systems＇ performance deterioration in traditional Internet applications due to the usage of parallel connections to transfer data and the occupation of too much bandwidth resource, the paper proposes an aggregate congestion control mechanism（ACCM） for P2P file sharing systems. By observing the share congestion in access links through the application-level measurement technology, the ACCM dynamically adjusts the window size of parallel transmission control protocol （TCP） connections, and achieves friendliness to tradition Intemet applications on the basis of maximizing the utilization of network bandwidth. The experiments demonstrate that the ACCM can decrease the size of the parallel connection window in the presence of congestion to achieve certain fairness with traditional Internet applications, and when the network is idle, the ACCM can increase the size of the parallel connection window to improve the utilization of network bandwidth resources.