R-Vivaldi:距离范围感知的IP网络坐标系统

R-Vivaldi: distance range-aware IP network coordinate system

分析发现,对需预测的节点间时延,若选择在该时延范围附近的节点作为锚节点,则能提高该时延预测准确度。基于此,提出了一种距离范围感知的IP网络坐标系统,即R-Vivaldi。其主要思路为:根据需预测的节点间时延的大致取值范围,在与该取值范围相近的一个距离半径的空间内,重新选择锚节点而得到它的一个新取值范围。依照该过程,被预测时延的取值范围更加明晰,并不断地动态调整锚节点的选择,直至节点间时延的预测误差满足一定需要。仿真结果表明,此方案能有效地提高距离预测准确性,而且在一定程度上克服了预测准确度不一致性问题。

The experience showed that the predicted delay＇s accuracy was improved when the nodes were chosen around the given delay as anchors. Thus a distance range-aware IP network coordinate system（R-Vivaldi） was proposed. The main idea was： according to the approximate range of the predicted delay, the anchors were re-selected in the radius area of the approximate range to compute the new range. In accordance with the above process, the coordinate system con- stantly iterated the network distance and dynamically chose anchors until the prediction accuracy meet the requirement. Experiments show that the approach can not only effectively improve the prediction accuracy of delay but also overcome inconsistencies of the prediction accuracy to a certain extent.