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A data center might look like a room full of black boxes, but it’s obviously a busy place. Every second, millions of packets come in from around the world, get moved through switches, and then sent back out at just about the speed of light. So it’s no wonder software-defined networking — an emerging networking architecture that speeds up switches, makes management easier, and gives IT managers more control over the network — is gaining in popularity.
So what exactly is software-defined networking?
Think of the data center as Grand Central Station in New York. If you were to arrive from Chicago, and you wanted to go to Boston, you’d need to switch trains. But there are dozens of ways through Grand Central that can get you there — what’s the fastest one? There might be a big human traffic jam around the subway entrance, or construction could be blocking access through the food court.
Without knowing about these conditions, you could get delayed very easily. But if you had an all-powerful, all-seeing pedestrian traffic cop who knew everyone’s destination and could tell them the best route to get there, everyone would breeze right through.
Software-defined networking is essentially a software-based “traffic cop” for all the packets that come through your customers’ switches. But what separates it from traditional, hardware-based “thinking” switches is that it uses software — which is much faster than physical switches — to do the thinking. At the click of a button, IT managers can define protocols on the basis of availability, efficiency, or capacity.