What is SD WAN and What Does it Do?

Even if you’ve only got a passing interest in business networking, you’re likely to have heard about SD WAN – or, to use its full name – Software Defined Networking as part of a Wide Area Network.

While there’s a lot of great information to be found online, there’s also a lot of information that misses the mark slightly – either over-sensationalising what the technology can do, or missing out key pieces of information.

To save you a lot of researching relating to SD WAN and what it can actually offer – we’ve put together a quick guide, dispelling some myths, and delving into what SD WAN might mean for businesses…

The SD WAN basics

If you want to understand what SD WAN is, it’s useful to have some knowledge of how a Wide Area Network (WAN) works.

A huge number of businesses have a WAN – but often don’t realise it. In simple terms, a WAN is a series of business locations connected through their IT tech – most often, their internet connection. So, for instance, a business has a head office in Mumbai, with offices in London and New York. That company would probably have their central IT infrastructure in Mumbai – but would have staff in Europe and America accessing the storage, systems, email – and so forth.

This is a WAN. In fact, the entire internet is also a WAN; a series of smaller, local area networks (LAN) connected through the internet.

How do SD WAN fit in?

Whether you’ve got offices that span continents – or simply hardware that’s in the next town or region, it’s useful to be able to ‘get hands on’ with it, without actually being in the same room. This is one of the major factors SD WAN offers.

When you’re starting to get to grips with SD WAN, it’s important to understand that it doesn’t replace any of your current WAN or IT infrastructure, instead, it offers a control system that works alongside it. This is significant though, as traditionally, working on a WAN has meant having IT technicians physically able to work on every part of your infrastructure – often meaning teams in different locations, or engineers having to travel to different sites quickly.

Now though, central log-ins to your SD WAN system will mean you’re immediately able to configure devices in all four corners of the globe.

Of course, it’s not just accessibility that SD WAN offers though, there are a host of other benefits…

A universal language

You may not realise it, but a host of different ways to transmit data also means a host of different languages or ‘protocols’ needed to make that data transmission work. So, information that’s sent over a 4G connection is handled in a different way to information that’s send over copper ethernet lines.

With SD WAN, the network is effectively ‘virtualised’ – meaning your control overlay is compatible with every data transport protocol. So, if your business uses SD WAN, you don’t have to worry about the hassle usually involved having different systems ‘talk’ to one another.

Central security

With a standard WAN set up, you’re almost certainly required to have security measures at every site. SD WAN removes this need – and instead, provides a way to deliver security in an over-arching manner, administered from a central location.

While you might traditionally think of network security as being a firewall – the way SD WAN works allows for delivery of any application or program, so, from firewall defence to browser content filtering – SD WAN gives you an amazing level of security control centrally.

Site provisioning

There’s something of a myth that says SD WAN will help you get your physical location online much more quickly than if you were provisioning a standard WAN location.

This is really only half true – but the positive half of the conversation is still a big benefit.

In reality, we know that the provisioning equipment on site is only half the battle when it comes to setting up a full location. SD WAN or not, you’re still going to have to wait for a circuit delivery – and of course, you’ll have to get your equipment to your site – but, when you do, that’s when SD WAN shines through…

Rather than sending fully configured devices to your site, you can virtually have devices shipped direct to your site as a blank canvas – before configuring them remotely, through your central SD WAN system. This is an enormous benefit and significantly reduces the logistical issues that surround bringing a WAN location online.

Class of service improvements

For organisations who have mission critical applications that keep their business running, SD WAN offers a huge benefit when compared to a standard WAN set up.

The benefit comes down to pathway control. Effectively, SD WAN allows for intelligent pathway control, making sure that your high priority traffic finds its way across your network, regardless of the load elsewhere. Rather than requiring this control to be acknowledged by each device, SD WAN can be configured so the control is pushed out to all devices – and can account for a significant number of variables.

Is SD WAN right for you?

When new technology is rolled out to businesses, there are always people who shout from the rooftops about the IT revolution that it will bring – and SD WAN is no exception. Don’t misunderstand, SD WAN is powerful, but it’s a system overlay – so, network problems at a design level will still be there.

SD WAN is no a replacement for intelligent network design, nor is it a replacement for MPLS connections – despite its intelligent pathway control ability.

If you’ve got a well-designed WAN that administered by an excellent in-house team or managed network provider, then SD WAN might not offer your business a huge amount. If, however, you’ve got a team of IT professionals that are stretched to the limit by your current WAN set up, the bringing SD WAN control of your infrastructure under your head office roof might be the perfect solution.

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