OpenFlow is a concept from emerging software-defined networking (SDN) technologies, which is intended to help users operate networks in a smarter way, with greater flexibility and efficiency. Compared to the traditional approach, SDN is itself a revolutionary approach, separating the network control plane and the forwarding plane. OpenFlow is shown to consume less energy compared to traditional hardware-based networking, an appealing characteristic for next-generation services and applications. Because it is programmable via an open protocol, OpenFlow is very flexible and varied in its implementations. It can perform network address translation (NAT) tasks such as rewriting packets, dropping packets as a firewall might, and keeping the network healthy by load balancing the packet flows.

The main contribution of this article is to introduce, in a practical way, the emerging OpenFlow concept as a key enabler for a wide range of applications and services for next-generation networks. Besides these main ideas, the author also proposes practical examples of applications and services using OpenFlow, such as in bandwidth management, tenantized networking, and game servers.

The article also contributes to debates on whether the OpenFlow paradigm is an evolution or devolution in networking technologies, with an analogy to the introduction of app stores in smartphone history. Furthermore, the author warns against oversimplification, which may complicate OpenFlow implementation due to networking complexity issues such as redundancy and failover mechanisms.

The author has successfully introduced a complicated new concept in networking in plain yet precise words. For those interested in networking, this article is definitely worth reading and contemplating.