Beehive: Towards a Simple Abstraction for Scalable Software-Defined Networking

Simplicity is a prominent advantage of Software-Defined Networking (SDN), and is often exemplified by implementing a complicated control logic as a simple control application on a centralized controller. In practice, however, SDN controllers turn into distributed systems due to performance and reliability limitations, and the supposedly simple control applications transform into complex logics that demand significant effort to design and optimize. In this paper, we present Beehive, a distributed control platform aiming at simplifying this process. Our proposal is built around a programming abstraction which is almost identical to a centralized controller yet enables the platform to automatically infer how applications maintain their state and depend on one another. Using this abstraction, the platform automatically generates the distributed version of each control application, while preserving its behavior. With runtime instrumentation, the platform dynamically migrates applications among controllers aiming to optimize the control plane as a whole. Beehive also provides feedback to identify design bottlenecks in control applications, helping developers enhance the performance of the control plane. Our prototype shows that Beehive significantly simplifies the process of realizing distributed control applications.