Article · 06 Jun 2018

What you need to know before embracing SD-WAN

SD-WAN is poised to transform the network. Here’s how you cut through the hype to work out what form of SD-WAN is right for your organisation.

CTO EMEAR Partners, Cisco

There’s still a lot of hype around SD-WAN and what it can offer the enterprise, further complicated by the fact that what the market said it wanted from SD-WAN two years ago is not what it wants today.

Getting caught up in the hype can mean that, for a CFO under pressure, SD-WAN can seem like a smart way to cut IT costs. Without the bigger picture, confusion and partial understanding have led to inflated expectations that SD-WAN can save around 45 per cent on current IT costs. This, in turn, means the head of networks faces C-suite requests to embrace SD-WAN as a way of unlocking savings by only using the internet for traffic. You can see where it comes from: after all, the biggest taxi company in the world doesn’t own any taxis, and the largest accommodation company in the world doesn’t own any hotels — so why does the enterprise need to own a network? 

The reality is that it’s far from that simple, and it’s not just a question of flicking a switch and turning on a SD-WAN, or about making a sudden jump to the internet. 

Starting your SD-WAN journey 

Start by thoroughly understanding the problem you’re trying to fix before taking any action, and bear in mind what you’ve currently got in your IT estate. Once you’ve cut through the hype and you think you have a need for SD-WAN technology, you must establish a clear line of sight to a business benefit before you begin. 

Not all SD-WANs are created equal 

Once you’ve identified the business benefits you want to achieve, you’re faced with a marketplace filled with solutions all wearing the ‘SD-WAN’ label. But not all SD-WANs are the same. There are broad things they can all do, such as traffic routing and prioritisation — but you’ll also find distinct differences. Some SD-WANs support more complex networks and multiple VPNs, some have more complex security requirements, some are more straightforward to install and manage, and some have different levels of routing. It’s important to understand the differences available to you as part of your decision-making process. 

The critical definition of service around your SD-WAN programme 

The level of control you want over your SD-WAN should be one of the early decisions you take when choosing your SD-WAN solution. Hype can get in the way here, encouraging you to buy in to the idea that you can control your entire network by clicking a few buttons on an iPad. In reality, although SD-WAN technology comes with lots of new portal capabilities that do give an enhanced level of control, many organisations don’t have the people, processes or desire to do it themselves. 

Deciding whether a fully-managed solution is right for you starts with a walk-through of how SD-WAN will work within your organisation. By projecting your way through your SD-WAN journey you can foresee what processes and resources you’ll need to have in place, and can work out what degree of management you require. You need to ensure you have the right support, skills, network and security for a successful solution. 

 Choosing when to start your SD-WAN journey 

Timing is an added dimension in your decision to evolve your network towards SD-WAN. If you go full steam ahead right now, what you’ll get is some of the potential capabilities and immediate benefits of SD-WAN. However, if you hold back a bit, you’ll get a more advanced version of SD-WAN, but with the trade-off of delaying the benefits. Basically, the longer you wait, the more virtualised services, complexities and advantages you’ll get — but at the cost of being without any of the benefits for a significant period of time.

Deciding whether to take the first steps to SD-WAN now, or to wait, depends upon what’s important for your business. It all comes back to finding trusted, expert advisors to help you make that decision. With the right support, you need to define the problem you want to fix and look at the technology that’s available now to address the issue. 

A successful SD-WAN needs a strong underlying network 

If you’re going to make the move into SD-WAN you need to make sure the network that will underpin your SD-WAN is robust. You need to remember that SD-WAN is an overlay technology and, because of this, it’s only as strong as its underlying network. If the network’s unreliable, overly complex, doesn’t have good governance, or isn’t well managed or understood, there’s a risk it’ll fall over in response to the smallest factor, such as someone making an error in changing a firewall. If you’re just using the internet, you need to be wary of traffic routing and the latency impact as well as additional services and security risks. You need to make sure you’re not just putting more complexity on top of an already complex lower network. 

Assess what you know about the applications on your network 

The next step is to thoroughly understand your applications profile. This is something of which many organisations, if they are honest, have limited understanding. The performance of applications is critical to the success of any deployment. There are two main ways of assessing your applications — using probes and analytics tools on your network to give you a view, or going ahead with an SD-WAN pilot and getting a lot of the data you need from that. Either way, it’s well worth the investment, and will avoid unnecessary wastage of time, resources and products. 

A software-defined future

We will increasingly inhabit a software-defined world. We’re already seeing the benefits in the data centre; what used to be the most costly and slowest part of the IT stack is now the fastest due to virtualisation and software-defined networking. Next, we’re going to see this capability coming into the WAN — and then on into the LAN. In the future, we’ll connect the data centre, WAN and LAN together and provide end-to-end services. This will mean you’ll be able to define a policy or criteria in one area of your IT and, where relevant, it’ll be carried across to the other parts. Security will be at the heart of this software-defined way of operating, and we’ll move away from focusing on endpoint security to an end-to-end approach. 

BT and Cisco: the story so far

BT and Cisco have been strategic partners for over 25 years, and have a history of innovating together to bring customers the best of new technology. A fundamental part of working together involves assessing each new hyped-up technology set and figuring out what’s going to stick — and, therefore, what’s going to be of most use to our customers. When I look back, BT and Cisco have been working in partnership at each key step in communications technology: we collaborated to build the industrialised internet; we innovated to move on from dial up to pay-as-you-go subscription services; we developed BT’s broadband and MPLS services together; and we were the first and largest provider of cloud-based enterprise telephony services. 

A partnership that provides a full SD-WAN service 

SD-WAN is just the latest in a long history of BT-Cisco innovation, and we’ve been investing in this area for years. Our partnership is much more than just reselling Cisco boxes. BT is taking the best of Cisco technology, integrating it into its own network and core technology, and wrapping it with its service, support and security capability to make a solution which is the best of both worlds. It’s the perfect approach to overcoming the challenges surrounding SD-WAN solutions.