一种提高异构网络传输性能的双向流量控制机制

针对异构网络存在的高误码率和不对称带宽等特点使TCP性能降低的问题,本文提出了一种双向流量控制机制BFC,它根据数据链路的双向通信状况, 在前后向两个信道进行流量控制.在前向信道,我们设计了一种显式的ACK详细指示方法,协调多层控制机制及时调节流量;在后向信道,提出了一个ACK流量控制算法,根据双向拥塞状况,对ACK流进行自适应地控制.实验表明,该机制可以有效地提高异构网络传输性能,尤其是当双向信道的不对称参数较高的情况下,该方法显示出独特的优势.

A Bi-direction Flow Control Mechanism Improving the Transfer Performance of Wireless Network

In order to solve the problem that performance of TCP is reduced due to higher bit error rate and bandwidth asymmetry in wireless networks,we put forward a Bi-direction Flow Control mechanism(BFC).It controls traffics in two directions.In the forward channel,according an explicit ACK notification BFC adjusts data rate by cooperating multi-layer protocols.In the reverse one,we developed an ACK flow control algorithm that adjusts self-adaptively ACK rate according to congestion status of two channels.The results of the simulation experiments show that BFC has dramatically improved the performance of TCP over wireless/wired hybrid links.Particularly,in the networks with higher asymmetric factor,BFC has significant contribution.