Timed Consistent Network Updates in Software-Defined Networks

Network updates, such as policy and routing changes, occur frequently in software-defined networks (SDNs). Updates should be performed consistently, preventing temporary disruptions, and should require as little overhead as possible. Scalability is increasingly becoming an essential requirement in SDNs. In this paper, we propose to use time-triggered network updates to achieve consistent updates. Our proposed solution requires lower overhead than the existing update approaches, without compromising the consistency during the update. We demonstrate that accurate time enables far more scalable consistent updates in the SDN than previously available. In addition, it provides the SDN programmer with fine-grained control over the tradeoff between consistency and scalability.