基于ECN的单播流与多播流间带宽共享算法

An ECN-Based Bandwidth Sharing Algorithm for Unicast and Multicast Flows

1引言 多播是一种实现多点传输的通信方式,和基于单播实现多点通信的方式相比,多播能有效节省网络资源.对于参与通信的用户数量较大的应用如音频/视频广播,多播的优势将更为明显.

An ECN-based implementing bandwidth-sharing algorithm for unicast and multicast flows is presented. The algorithm uses a bandwidth allocation strategy to give an incentive to multicast flows in bandwidth allocation according to algorithm of the number of receivers, and to assure the unicast flows get their bandwidth shares fairly. Provided best-effort networks, an ECN-based congestion control algorithm is used to implement differentiated service in bandwidth allocation between unicast flows and multicast flows. In implementation, we solve the problems such as receiver's number estimation, the RTT estimation and compromise between convergence and stability. The simulation results show that the algorithm can implement bandwidth sharing for TCP flows and multicast flows. At the same time, the algorithm not only allocates more bandwidth to multicast flows, but promises TCP flows to get their fair bandwidth share.