Verification of Configuration Management Changes in Self-Organizing Networks

The verification of configuration management (CM) changes is an essential operation in a mobile self-organizing network (SON). Usually, a verification approach operates in three steps: it divides the network into verification areas, triggers an anomaly detection algorithm for those areas, and finally generates CM undo requests for the abnormally performing ones. Those requests set CM parameters to a previous stable state. However, the successful completion of this process can be quite challenging, since there are factors that might negatively impact its outcome. For instance, if a temporal degradation occurs during the optimization of a cell, a verification mechanism may wrongly assume that it is anomalous, and interrupt the optimization process. Furthermore, a verification strategy experiences difficulties when it faces verification collisions, i.e., conflicting undo requests that cannot be simultaneously deployed. At first, it has to determine whether the collision is a false positive one. Then, it has to resolve it by finding out which requests have the highest probability of restoring the network performance. In addition, it needs to consider the time that is given for rolling back CM changes. In this paper, we contribute to the area of SON verification by providing a solution that addresses those problems. Our approach makes use of constraint optimization techniques to resolve collisions as well as find the appropriate order for deploying undo requests. In addition, we use a minimum spanning tree-based clustering technique to eliminate false positive collisions. Further, we evaluate our solution in a simulation study in which we show its positive effect on the network performance.