Let’s get this straight – what is SDN?

I recently contributed to a CBR post asking how you explain SDN to a five year old. It’s not often that I have to bring things to a primary school level, but describing SDN in laymans’ terms is a question with which I am regularly approached.

SDN enables us to deliver what our customers want and need from their network architecture. They want to have the agility to respond to changes in the market and spin up new applications and services with a significant degree of automation, creating an elastic environment which supports end users with a self-serving model.

The concept of SDN is responding to rapid deployment of applications in the market. It used to be the case that new applications took months and, sometimes, even years of development before becoming part of the business. Nowadays, applications are spun up almost overnight and discarded as a learning if they don’t hit the right note – making for very different demands on the network.

Much of the conversation around SDN to date has centred around the network (layers 2-3) and in improving service velocity for the network. However, it’s essential that businesses also tackle the velocity of application services (layers 4-7) in order to realise the full benefits of SDN. After all, it's the operational side - the deployment, provisioning, monitoring and management of the applications that directly impacts service velocity.

What we’re seeing today is that many customers, particularly in the financial services and service provider sectors, are testing proof of concepts – kicking the tyres if you will. It’s a case of working the SDN logic into the blueprint of their network architectures, taking out much of the manual process and automating for greater speed and agility. In my view, it’s only a matter of time before SDN becomes the norm as businesses shift from legacy to new environments.

So how would I explain SDN to a five year old? "SDN is like having the power to make new things, at the touch of a magic button – or even just by thinking about it! Imagine having a big shiny button on your bedroom wall and every time you want to do something faster or in a different way, you just press it and it happens. Just think, if you want to get to school faster, you could hit the button and a speedy slide from your bedroom window to the school gate appears. Or if you want the game you’ve ordered to arrive faster, just hit the button and, quick as a flash, the world’s fastest car drops off the delivery man with your new game!"

For businesses, it’s a concept which is going to ensure they can compete in their field and deliver services their customers demand, at the drop of a hat.