What is the advantage of cooperation in self-organizing networks?

Self-organizing network (SON) functions can be characterized by their required cooperation between the network elements (NEs). The cooperation among the NEs can include a multitude of possible actions, such as reporting of alarms or coordination of joint parameter modifications at multiple NEs. However, the question for the advantage of cooperation among the NEs in SONs is still an open research topic. By limiting the cooperation between the NEs, the required architectures for utilizing the SON function at hand can be simplified, which in turn can lead to cost savings. In this paper, we investigate the impact of degraded cooperation among the NEs on the SON architecture required and on the performance in a joint capacity and coverage optimization (CCO) use case. For the scenario investigated, we observe that the performance decreases dramatically when decreasing the cooperation among the NEs. However, we can also show that the exchange of information, such as the values of considered key performance indicators (KPIs), among the NEs is more important for an efficient operation than the coordination of the NE's actions. Our results show that, a centralized approach outperforms distributed and localized approaches for the CCO use case investigated.