摘要
针对TFMCC算法速率振荡大的局限性,提出了一种基于模糊PI-PD的组播拥塞控制算法(FPI-PD-MCC:Fuzzy Logic-based Proportional Integral-proportional Derivative Multicast Congestion Control Algorithm)。在FPI-PD-MCC中,对发送方的速率调整步长进行了平滑,在路由器中引入了PI控制,并利用模糊逻辑计算参数α,从而自动调节丢包概率以缓解拥塞。仿真结果表明,该算法能够使队列长度稳定在期望值附近,同时保证网络吞吐量的平缓变化。
A fuzzy logic-based proportional integral-proportional derivative multicast congestion control algorithm (FPI-PD-MCC) is proposed in the paper. The algorithm adjusts its transmission rate to smooth its rate adaptation. The PI controller is introduced into the router, while the parameter of a is calculated based on fuzzy logic, which could regulate the loss rate automatically to alleviate the congestion situation. Simulations show that the FPI-PD-MCC algorithm could preferably maintain the queue length around a desired level, and guarantee the stability of network throughput.
出处
《通信技术》
2009年第5期149-151,154,共4页
Communications Technology
基金
陕西省自然科学基金资助项目(SJ08F14)。
关键词
组播
拥塞控制
模糊逻辑
PI
PD
multicast
congestion control
fuzzy logic
proportional integral
proportional derivative