WAN vs SD-WAN: What’s the difference?

WAN vs SD-WAN Banner


It’s a connected digital world we live in, and every organisation is beginning to pay closer attention to their networks as a key driver of performance and productivity. No matter what industry we operate in, every organisation needs to provide end-users with seamless connectivity and secure performance.

That’s increasingly difficult when we consider the vast range of devices our employees and customers use to access our networks. They’re also using a multitude of cloud-based applications that need the ability to transfer data back and forth between our on-premise and cloud platforms and databases.

This is all leading to a great deal of discussion about Wide Area Networks (WAN) and Software-defined WAN (SD-WAN). You would have likely seen these terms before but you may still be unsure what they mean. Here’s a quick guide to both and which is ideal for you organisation.

Wide Area Networks (WAN)

For the most part, Wide Area Networks have mostly depended on dedicated infrastructure and supporting technologies such as Multiprotocol Label Switching (MPLS) which are then connected by your carrier (Telstra etc). To connect multiple sites in a traditional legacy WAN, you needed to build a physical network that connects back to a physical data centre, and then ask your carrier to guarantee you a certain level of bandwidth each and every month.

This structure has worked fairly well in previous decades when your remote sites simply needed access to a central data repository. But today’s new demands for connected cloud-enabled services means that the WAN is increasingly complex and expensive to maintain:

  • • Legacy WAN requires capital investment in physical networks and infrastructure.
  • • MPLS networks offer limited visibility into how and when network traffic is being used.
  • • Remote offices access and generate data in far more dynamic ways than they used to.


According to 2018 research from Frost and Sullivan, SD-WAN was deployed or underway in 33% of the organisations surveyed, and 61% of organisations intend to deploy SD-WAN in the next two years.

SD-WAN is growing in popularity as it offers a simple way to lower costs and complexity. Rather than focusing on physical locations and the equipment/cables required to connect them, SD-WAN creates an abstracted (software-defined) network layer via the cloud.

This doesn’t mean all of your WAN/MPLS network investments need to go to waste, however. SD-WAN simply allows you to manage data flows over internet and cellular networks, as well as your MPLS network. Your SD-WAN can be deployed to operate in concert with, and to complement, your existing WAN infrastructure:

  • • Rather than bandwidth decisions being decided by your cables and carrier, you can make decisions on which connectivity policies suit each site.
  • • Policies then intelligently monitor and control network traffic to ensure performance service level agreements are achieved.
  • • SD-WAN is much faster to deploy, and can be up and running in a matter of weeks, as opposed to months in the case of WAN.

According to IDC, one in four organisations can expect cost savings of up to 20-39% by deploying SD-WAN, and the majority of businesses can expect savings of at least 5-19%.

Softsource now delivers Aruba’s industry-leading SD-WAN through the cloud for a simple monthly fee. To find out if our industry-leading Network as a Service (Naas) is the right fit for you, simply book a consultation with a Softsource Network Specialist to discuss your current capabilities and strategic direction. Our team of network experts will then make recommendations, and architect the best solution to meet your specific requirements and budget.