Evaluating the Impact of Inter-Cluster Communications in Edge Computing

Distributed applications based on micro-services in edge computing are becoming increasingly popular. Kubernetes is the default framework for orchestrating and managing micro-service-based applications. Notwithstanding, the requirement to run applications between multiple sites at cloud and edge poses new challenges since Kubernetes does not natively provide tools to abstract inter-cluster communications at the application level. In this paper, we evaluate for the first time the impact of inter-cluster communication on edge computing performance by using three prominent, open-source inter-cluster communication projects and tools (Submariner, ClusterLink, and Skupper). We develop a fully open-source testbed that integrates these tools modularly and experimentally benchmark sample applications on their performance running in a multi-cluster edge computing system under varying networking conditions. We experimentally analyze two classes of envisioned mobile applications (industrial automation and vehicle decision drive assist). Our results show that ClusterLink performs best out of the three tools in scenarios with increased payloads regardless of the underlying networking conditions or transmission direction. Skupper closely follows it unless requests and replies transport big payloads. Finally, for small payloads, Submariner slightly outperforms the other tools.