一种基于链路传输延迟的MPTCP拥塞控制算法

摘要

由于传统TCP拥塞控制算法直接应用到MPTCP(Multipath Transport Control Protocol)中存在公平性问题,以及不能有效地发挥多路径传输的优势,因而从公平性方面对MPTCP现有拥塞控制算法进行研究.研究发现,现有的MPTCP拥塞控制算法均受到相同的回路时间限制.提出一种基于链路延迟的RTT补偿算法(Compensating for RTT mismatch,C-RTT ).该算法通过设置网络带宽占用比参数以及对MPTCP连接的子流设置侵略因子,从而保证瓶颈链路处MPTCP数据流和TCP数据流公平地共享可用带宽.最后通过NS3仿真实验证明,该算法能够有效地补偿链路中因RTT不等引起的公平性问题,并避免链路之间数据的非周期抖动,且保证了多路径传输的优越性.%As the traditional TCP congestion control algorithm in the application of MPTCP (MultiPath Transport Control Protocol) existing fairness issue, and not effectively playing the advantage of multipath transmission, hence the issue of fairness on the bottleneck link in MPTCP congestion control algorithm is researched. Through the research, it is found that existing MPTCP congestion control algorithms are limited to the same round-trip time. In this paper, a new algorithm named Compensating for RTT mismatch is proposed, which by setting a parameter of network bandwidth occupancy, and setting a aggressiveness to subflow in order to ensure share available bandwidth between MPTCP data flow and TCP data flow fair at the bottleneck. Finally NS3 simulation results prove that the algorithm can compensate performance deterioration of the link due to the RTT mismatch, and avoid the link between non-cycle jitter, and ensure the superiority of the multi-path transmission.