目前绝大多数带宽测量方法都是基于网络瓶颈分隔原理的,在此基础上形成了基于包对/包队列的各种容量/可用带宽探测方法.但是,这类方法的测量结果不能超过源节点的最大发送速率,因此无法在高带宽环境中使用.另外,目前的可用带宽测量理论均没有考虑背景流的不同路由对测量方法所产生的影响.全面分析了背景流的路由时可用带宽测量的影响.在此基础上,基于蒙特卡洛(Monte carlo)随机抽样的思想,提出了一种与现有测量方法截然不同的探测理论.该方法用随机发送单个小探测报文取代了目前的探测理论所依赖的包对/包队列,其测量范围不受源节点最大发送速率的限制.分析及实验表明,该方法不仅可以计算整条路径的可用带宽,也可以计算各段链路的容量和空闲率,进而分析得到各路由节点上的流量变化,以及各链路上对应的不同类型的背景流的分布,
A majority of current bandwidth estimation methodologies rely on the principle of the bottleneck spacing effect. Based on the concept of packet dispersion, many packet pair/packet train techniques were presented to estimate capacity/available bandwidth. However, these methods failed for measurement on high capacity path, because they could not measure bandwidth beyond the source node's maximum sending rate. In addition, current methodologies do not consider the effect of cross traffic routing on available bandwidth estimation. This paper analyzes the effect of the routing of cross traffic packets on available bandwidth measurement in detail. Then based on Monte Carlo Method, a novel methodology funda mentally different in the basic idea from the previous methods is presented to measure end-to-end available bandwidth. This method sends small single packet randomly instead of sending packet pair/train back-to-back. It could work on network whose capacity is far beyond the maximum sending rate of the sender. Analysis and simulations show that besides end -to-end available bandwidth, this method could measure the capacity and idle ratio of targeted link, and then calculate the change of traffic flow on each node and the percentage of different cross traffic on each link.