Nathan Pearce, Cloud and SDN Product expert, F5 Networks
"Software defined networking (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!"
Jennifer Pigg Clark, VP of Mobility Research, 451 Research
"You know how when you drive somewhere with you parents lots of times one parent (maybe your Dad) does the driving and the other parent (maybe you mom) tells him where to turn? That's just how network traffic works - someone has to drive the information but someone else has to know where to turn so the information gets where it's going.
"SDN is like having GPS. Someone still needs to drive the car, but mom can stay home, because the GPS system will tell Dad where to turn. Not only that - it can tell all the dads, in all the different cars, where to turn. So that's a lot simpler, it's faster, there are fewer fights, everyone's happy and all the moms can get together and go do something else - like go to the pool with you, or build a new civilisation - fun stuff."
Andy Chew, Cisco's UK & Ireland Managing Director of Architectures
"By 2020 there will be fifty billion things connected to the Internet - or the information super highway as we used to call it in the 1990s. The more devices we use, the more network traffic we'll experience - if this continues unchecked the information superhighway is likely to become one very big and congested traffic jam!
"Software Defined Networking (SDN) is an approach to networking that will help reduce and alleviate this traffic congestion by being able to programme the 'highway'. SDN works by separating the network control-plane, think of this as a traffic update on the radio, from the network devices, think of these as the cars.
"By being able to differentiate critical applications (suggested new traffic routes) from noncritical ones (sitting in the traffic jam) it allows companies to dynamically allocate network resources to higher-priority applications - thereby increasing traffic flow and making sure the road stays clear."
Stu Bailey, founder and CTO, Infoblox
"Think about the tablet you use to watch videos and play games, or the phone your Dad uses to check his email or the laptop your Mum uses for work. These are all different kinds of computer.
"Imagine each of these computers is a city full of people doing different things. Today, these cities are connected by highways with cars carrying people back and forth, so one computer can talk to another. These highways have traffic lights and traffic jams and car crashes that slow things down.
"Now, let's imagine each computer city has a magic balloon around it. When ten or twelve or even a thousand computer cities want to talk to each other, the people inside make the cities float around and find each other! No more highways, no more cars, no more crashes. As long as two magic balloons are touching, the people inside can talk and visit. This magic world is called SDN, and it's how computers will talk to each other before you're in high school."
Dr Nick Race, senior lecturer at School of Computing and Communications at Lancaster University
"Ever been lost or stuck in traffic and wanted advice on exactly the best way to reach your destination? You might ask a passer-by, who helps you get closer to your destination - only for you to run into more traffic. You turn back, looking for another route. This is very much like how today's computer networks operate.
"Now let's imagine the same scenario using SDN. SDN is the networking equivalent of having a reliable, up-to-date mapping application for your smartphone: retrieving the very latest maps, using GPS to plot your location with a central server constantly calculating the best route for you to take. The power of SDN is the software: running on a central server it has a complete picture of the network and can give you the most up-to-date information to help guide you to your destination and avoid those annoying jams."
Ed Ogonek, president and CEO, CENX.
"The Internet is like a kindergarten classroom - where the teacher asks you to pass a ball from the front of the room to the back and each of you decide on your own what is the best way to do so. The ball likely moves in a haphazard manner from one child to another, even touching some multiple times. You may pass it, roll it, throw it, or even drop it.
"A Software Defined Network is one in which the teacher first lines you all up in a straightforward line, tells you to take the ball from the child on your right and pass the ball to the other child on the left. And you do what you're told. This saves you a lot of time since the ball gets to the back of the classroom much faster."
Mike Fratto, principal analyst of Enterprise Network Systems, Current Analysis
"Regular networking is like playing soccer or kick ball. You play a position and your friends play other positions. You know what to do but sometimes your coach or team mates yell out suggestions. You may or may not do what they say, but you're all trying to make a goal. SDN isn't like that. SDN is like a school play. You all have your costumes wear and lines to learn. Your teacher organizes you into places. Then you go on stage and you read your lines and if someone goofs, you fill in. In the end, the audience applauds."
Stuart Greenslade, sales director of EU networking, Avaya
"The benefits of SDN can be likened to removing the constraints of the existing plumbing in your house, when you are refurbishing it. For example when planning a new kitchen you might want to place the sink in the middle of the room because there it would be equidistant between the fridge and the cooker and therefore in the most practical location.
"However you may find that this isn't possible and that the sink has to be in the corner, because that is where the existing water and waste pipes come into the kitchen. In an SDN environment, network managers are no longer constrained by 'the plumbing' - i.e. they would be able to locate the sink in the most useful location, and even move it around several times, regardless of where the pipes are.
"Software simply becomes a toolset and the network manager can move to focusing on solving business problems, not overlaying a software vision on top of business problems. Vitally, SDN allows network managers to really concentrate on the services that their network or data centre delivers - they can organise their networks by use and make them more flexible."
Akshay Sharma, researcher director of Gartner's Carrier Network Infrastructure Group
"It's all about bringing the puffy clouds and the stars in space to you and to your toys here on Earth, and this will allow you to have your toys move to the puffy clouds and the stars in space, so you can play with them across other places, and on other devices: TVs, smartphones, tablets...and to enjoy them as you like, and share them with your friends too, and keep everyone happy..."
Clive Hamilton, VP Network Services at NTT Europe
"Think of a network as a football pitch and the ball is the data you want to deliver. Each player has his or her function on the pitch; the striker, the defence and so on. And they all have to work together to deliver the ball to the back of the net.
"But rather than them all having their own opposing strategies on how to achieve this or working individually, which would be chaotic and an impractical use of resource and their individual skills, they need someone to bring them together.
"SDN is the football manager who defines and executes the overarching game plan and strategy. It can also change the game plan in real time to take account of events on the field, such as injuries (downtime and glitches) or a tackle by the opposition that takes a key player down (network conditions that prevent the delivery of the ball, such as network congestion)."
Don McCullough, Director Strategic Communication at Ericsson
"SDN is like when I let you use my pots and pans to play games instead of cooking dinner. You are like a startup company thinking of new ways to have fun, that is great. But I still have to cook dinner, so you must clean them off and give them back to me at the end of the day. The SDN controller is like me letting you think up new ways to play with my pots and pans. It opens up the network so that many different people and companies can try new ideas that will benefit people all around the world. But it also sets up rules that make sure that the network is protected and maintained properly."