Stateful OpenFlow: Hardware proof of concept

This paper presents a hardware implementation of Openstate, an extension of OpenFlow that allows performing stateful control functionalities directly inside the switch, without requiring the intervention of an external controller. The paper shows how, with a minimal reworking of the OpenFlow´s basic architecture, and reusing the same building blocks, it is possible to greatly extend the intelligence of an OpenFlow switch allowing the offload of many control task directly in the switch. An FPGA based implementation of an Openstate prototype is here presented, the different architectural design choices are discussed, and the performance and limitations of the developed prototype are examinated. Finally, the paper proposes a discussion on the performance achievable by using an ASIC implementation of the OpenState switch1.