SD-WAN: Separating fact from fiction

It’s rare that an emerging technology in the world of networking attracts as much attention as the much talked about SD-WAN. Some of the claims would have you thinking it was the cure to all your networking problems. Some of the more outlandish claims are rooted in a lack of understanding of what the technology can actually provide. To get to the core of what makes SD-WAN so appealing, you need an understanding of how the WAN got where it is and why there’s so much talk about WAN transformation.

Over the last few decades, the perfect storm of increased cloud adoption, IoT, mobility and BYOD has placed an unprecedented amount of pressure on IT professionals to transform WAN infrastructure. Digitally transformed organisations were moving rapidly from a state of technology-dependent to technology-enabled.

Network management suddenly became more than just a function of keeping the lights on. It became a strategic element of business delivery. Of course, with such a dynamic landscape, it was difficult, or at least expensive, for an organisation to retain the level of technical expertise needed to effectively monitor and manage the network. As a result, the industry saw a significant shift towards outsourcing network management and employing third party specialists to provide a managed network service.

Storage and computing power had already undergone its virtual revolution, so it was a logical next step to virtualise the network itself. This brings us to the software-defined network. The primary appeal of SD-WAN is the ability to “decouple” the network hardware from its management, making it possible to dynamically optimise traffic flow across the network in real time.

If it just stopped there, there wouldn’t be the confusion that prevails today. SD-WAN is now talked of in terms of a low-cost replacement for MPLS networks. This is only partly true. If you are extending your network, growing out for the edge, then SD-WAN is a cheaper alternative to putting in new MPLS services. However, few organisations are rushing off to rip out their existing MPLS networks.

MPLS has a lot going for it. Traditional WAN infrastructure may be a little more expensive, but it delivers security, reliability, predictability and quality of service. All of which are good things for organisations who rely on a guaranteed level of performance to run their critical business operations. Rather than being seen as a replacement technology, SD-WAN should be seen as a complementary solution, offering the enhanced benefits of agility, simplicity and cost-efficiency. But not all solutions are made equal. When direct internet access is part of your WAN, security is always a key consideration and those solutions which offer in-built security mitigate the risk that greater exposure to the public internet inherently brings.

SD-WAN is an overlay technology. Sitting on top of your traditional network infrastructure, it provides greater visibility of network utilisation, enables real-time traffic management and allows for more cost-efficient network expansion. For organisations with international sites, those subject to mergers and acquisitions or simply adding new sites as they expand, there are some clear benefits in terms of speed of provisioning and bringing new sites into the fold.

A major benefit of SD-WAN is the granular level of control you can exert over your network with intelligent routing enabling traffic prioritisation and centralised policy management allowing for configuration changes to be rolled out consistently across all end-points. It is this very degree of control that has drawn the outsource or inhouse debate back to the table. It is important to note that there is no single right answer to the “should I outsource to an MSP or do it myself” question. It depends entirely on your individual circumstances and requires careful consideration of what your core competencies are and where your focus needs to be. It’s worth bearing in mind, the over-arching rationale for choosing a managed service which allows organisations to concentrate on their priorities while leaving management of the network safely in the hands of a provider who has the time, skills and experience to achieve the outcome you want. To give just one example, with greater choice of connectivity and suppliers comes greater management burden, and having a single point of contact to resolve problems remains a strong benefit for any organisation dependant on critical IT infrastructure to underpin business performance and deliver consistent customer service.

For small businesses with modest bandwidth requirements, an on-premises solution may make sense. But for multi-site organisations with complex network dependencies, the inherent complexity remains. Whilst the SD-WAN makes management easier, there are still a lot of moving parts. The benefits of using a managed service in this instance remain.


Whether you’re considering the implementation of SD-WAN for the first time or looking to make the most of your current solution, we’re here to help. Contact us on 0800 983 2522 for more information.

Related Posts

Why Redcentric For Connectivity

MPLS WAN – your questions answered

What is MPLS technology? Multi-protocol Label Switching, or MPLS, is a networking technology that routes traffic intelligently using the shortest path based on “labels” rather than the complex...

Secure remote working

Secure SD-WAN: peace of mind for your network

Like almost every technology innovation ever, for every problem it solves, it trails another along in its wake. Take SD-WAN. It’s a popular choice for those looking for MPLS-level Quality of Service...

Why Redcentric IP Telephony

SD-WAN: A Buyer’s Guide

There is a growing buzz around SD-WAN as a network solution. It brings considerable benefits for some use cases but it isn’t a silver bullet for networking.



0800 983 2522