Unless you have been living under a rock for the last couple of months, you have probably heard of software-defined networking. And you have heard it from different angles. Undoubtedly, SDN is the biggest buzzword in the networking industry today, with every networking vendor worth its salt busy making plans for this brewing revolution. We haven’t seen any innovation in the networking space for the last two decades or so, and in this time networks have become complex, expensive and difficult to manage. SDN promises to change the game and is hailed by vendors as the biggest transformation that will change the future of networking. But what exactly is SDN? For the uninitiated, it means decoupling the control plane from data plane, making it remotely accessible and customisable through open protocols such as OpenFlow. In other words, it lets you programme your network as if it were a computer, and customise it to your local needs and eliminate unwanted features without having to touch hundreds of devices through a logically centralised control plane.
One of the extolled virtues of SDN is the ability to configure and control traffic through software, which gives network engineers the ability to innovate freely and make networks simpler and less expensive. Imagine every application in your data centre having its own network and you will get an idea of the flexibility and scale SDN promises. The good news is that SDN is no longer a research project with major vendors including Cisco, Juniper and HP making significant product announcements, and some of the early adopters such as Google have shared positive news about the impact of the technology on network performance. Google, which runs a full production SDN in one of its data centres, has been able to target network failures more quickly and gain concentrated control over the network, simplifying the whole environment. In the wide area, it has even reported nearly hundred percent link utilisation while the industry average is 30-40%. Sounds like nirvana? SDN might just be the manna from heaven for those who requite network adaptability and scale with reduced cost and vendor independence.
