ONF Connect 2019

Current SDN controllers follow a monolithic approach that integrates all services and applications into one single, huge program. The monolithic design of SDN controllers restricts programmers who build management applications to the specific programming interfaces and the specific services that a given SDN controller provides, making applications dependent on the controller, and thereby restricting portability of management applications across controllers. Furthermore, the monolithic approach means an SDN controller must be recompiled whenever a change is made, even if the change is minor; the approach does not provide an easy way to add new functionality or scale to handle large networks. To overcome the weaknesses inherent in the monolithic approach, the next generation of SDN controllers must use a distributed, microservice architecture that disaggregates the control plane by dividing the monolithic controller into a set of cooperative microservices. In this talk, we consider two potential designs for externalization of event processing, a critical first step involved in moving from a centralized, monolithic design to a decentralized microservice control plane architecture.