VCP协议最大最小公平带宽分配的实现与仿真

Improving VCP to Achieve Max-Min Fair Bandwidth Allocation

变结构控制协议(VCP)是一种高带宽时延乘积网络环境下良好的拥塞控制机制。然而在多瓶颈网络拓扑中,由于VCP采用基于负载因子编码的反馈控制机制,长距离数据流的过载响应受传输路径上多个节点的控制,从而系统达不到最大最小公平。通过分析VCP的拥塞信息反馈方式,提出一种基于过载周期的反馈控制机制,使每个数据流的过载响应只受其瓶颈链路的控制,从而使系统达到最大最小公平。最后利用NS2仿真实验验证了基于过载周期的反馈控制机制的有效性。

Variable-structure congestion Control Protocol（VCP） is an effective congestion control mechanism for high Bandwidth-Delay Product（BDP） networks.In the multiple bottleneck network,however,the congestion signal of VCP is feedback based on encoded load factor;as a result,the overload responses of long flows are controlled by multiple routers in the transmit path,and failed to achieve max-min fairness.To address this problem,the congestion signal is feedback based on a new metric called overload period in each router,and the overload response of every flow is controlled by the router with minimum overload period.The proposed mechanism improves VCP to achieve max-min fair bandwidth allocation.Finally,the improved control mechanism is validated using NS2 simulations.