SD-WAN and MPLS: fight to the death or strategic alliance?

When SD-WAN first started to gain traction, a lot of people predicted it would kill MPLS.

There were good reasons for that opinion. Traditional WANs aren’t well-suited to the cloud era where traffic from business-critical apps and services is destined for the internet. The traditional MPLS practice of backhauling to a central hub doesn’t allow for the performance that many cloud services demand, and MPLS costs can mushroom if capacity is increased to cope with the demand for internet connectivity.

Our research shows that more than a quarter (26%) of organisations are looking at SD-WAN to support ongoing migration to the public cloud. So now that SD-WAN is beginning to be adopted, is the prediction on the decline of MPLIS is proving to be correct?

Complementary approaches

Far from it. What we’re actually seeing is that SD-WAN and MPLS work together very effectively in an environment where businesses are moving more and more data and apps to the cloud, and there’s still a need for secure private communications with guaranteed performance. At the same time, many organisations are under increasing pressure to become more agile without increasing costs to unrealistic levels.

Hybrid WANs that can route traffic over MPLS or internet connections give more flexibility to meet the different price and performance needs of different types of application. As cloud adoption continues to rise, the desire to better leverage the cloud for SaaS and improved performance means that application-layer visibility and control over the network becomes increasingly important.

However, working at the application layer with a cloud-enabled hybrid WAN can create policy complexities – and that’s where SD-WAN comes in.

SD-WAN prioritises, routes and secures traffic at the application layer by creating an ‘overlay’ (a virtual abstraction of the underlying physical network). This allows SD-WAN to create different WAN configurations and policies for each application, improving performance and boosting security and control. This is crucial for European businesses: 67% of organisations say a vital SD-WAN feature is granular control of hybrid WAN connectivity.

Instead of manually configuring individual devices in a traditional WAN, SD-WAN allows a whole network of devices to be automatically configured to achieve the connectivity objectives of any individual application. This helps with network scalability, saves huge amounts of time and resource, and also removes potential human error, which can have major knock-on effects on the business.

Recent global trends have shown an significant increase in the adoption of cloud-based applications such as video conferencing for end users and branches. It is likely that this trend will increase  as individuals and organisations find a ‘new normal’ in light of the COVID-19 pandemic.

Find the skills to make it work

SD-WAN technology is still maturing, so there’s a lot of value in buying the underlay connectivity (be that MPLS or Dedicated Internet Access) with the overlay SD-WAN as a complete solution from an experienced service provider that can offer the skills and expertise that can be hard to find in-house.

Your provider should be able to help identify which elements of the routing should be operated at the underlay and overlay layers to create the optimal solution. As the technology matures, more and more elements can be pushed towards the SD-WAN layer. By working with a supplier with an extensive global backbone, this also ensures that as your business and network requirements grow you are well partnered for the future.

So, we’re seeing that businesses still need the guaranteed end-to-end performance of MPLS, as well as the scale and cost-effectiveness of high quality and low latency internet that is extensively peered. By supporting a hybrid WAN with an SD-WAN overlay, organisations can get the best balance of performance and price.


Statistical source: IDG Connect study: Dynamic Connectivity and Intelligence in the Network, commissioned by CenturyLink. IDG Connect surveyed 339 IT decision makers in organisations across France, Germany, the UK and Benelux countries.