基于AS拓扑结构与网络服务分布的AS节点关键度分析

Analysis on AS nodes criticality based on AS topology and network service distribution

为了评估AS节点在实际网络中的关键度,有效发现实际网络中的关键AS节点,提出了基于加权有效最短路径定义的介数评估AS节点关键度的方法.首先根据valley-free原则计算有效最短路径,避免了一些在实际网络中无效的路径对衡量关键度的影响.进一步通过DNS测量网络重点服务在自治域内的分布情况,结合节点的网络服务权值衡量节点的实际关键度,克服了单纯从拓扑性质上无法较好地反映实际网络中关键度的问题.实验中根据AS关系数据集构建国内范围的AS拓扑模型,利用该方法对AS节点进行排名,并通过与基于介数和基于有效最短路径定义介数的评估方法的比较,验证了该方法能更好地分辨出节点对于实际网络中流量传输、服务提供的关键度.

To evaluate the criticality of AS nodes in the actual network and discover the key AS nodes in the Internet,a method for evaluating the criticality of AS nodes based on the betweenness defined by the weighted valid shortest path is proposed. First,the valid shortest path is calculated according to the valley-free principle,avoiding the influence of some invalid paths in the actual network on the measurement of criticality. Further the distributions of key services in AS are measured by DNS and the network service weights of nodes are combined to measure the practical criticality of nodes,solving the problem that the criticality of nodes in the actual network cannot be better reflected by the topological property alone. In the experiment,the AS relationships dataset is used to establish the domestic AS topology,then the rankings of AS nodes are given by using the above method. The results show that compared with evaluation methods based on the betweenness and the betweenness defined by the valid shortest path,the proposed method can more precisely identify the criticality of nodes for traffic transmission and service delivery in the actual network.