OpenNF: Enabling Innovation in Network Function Control

Опубликовано 21 июня 2016, 21:39

The benefits of using software network functions (NFs), also called middleboxes, and software-defined networking (SDN) together is greater than the sum of parts. Operators can deploy novel management applications to optimally meet performance, security, availability, and cost objectives for their networks. However, such applications need the ability to effectively manage the distributed processing happening at multiple NF instances in a deployment. We argue that this requires a framework that provides precise, joint control over both the traffic forwarded to and the internal state maintained at each NF instance. To this end, we design a control plane called OpenNF. Our design faces several challenges: how to allow applications sufficient flexibility in the objectives they optimize, how to accommodate several types of NFs, and how to avoid possible race conditions when exercising joint control. We address these through careful design of APIs, and two novel constructs—an event abstraction and a two-phase forwarding update. Our evaluation shows that OpenNF offers generally efficient state control without compromising application flexibility, and requires modest additions to NFs with minimal impact on NF performance.