Software-defined wide area networking (SD-WAN) has moved past the buzzword phase to become a rapidly proliferating technology that is here for the long haul. It is arguably the best option for businesses building or managing long distance networks.

What is SD-WAN?

SD-WAN distributes network traffic across WANs.  Especially useful for businesses with multiple branch locations, it’s a technology that uses software-defined networking (SDN) to route network traffic intelligently across branches and data center sites. Put simply, SD-WAN simplifies the complications of network technology.  SD-WAN comes in two main forms: overlay SD-WAN or network as a service.


Overlay SD-WAN verses Network as a Service

Overlay entails a Vendor-provided edge device which includes necessary software along with the orchestrator. Plug-and-play; the customer simply plugs in the WAN links, and the device configures itself off of the SD-WAN orchestrator. Network as a service you can access your own private networks and complete WAN optimization, traffic prioritization, and other functionality are typically included.


SD-WAN offers businesses a multitude of benefits. Most notably:

  • Connection resiliency
  • Network visibility
  • Intelligent packet routing
  • Rapid deployment
  • Improved network management
  • Improves application performance via WAN optimization techniques and dynamic routing of traffic based on application needs.
  • Automatic failover redirects traffic from failed or congested links to a different link, which reduces latency.
  • Intelligent prioritization of traffic reduces reliance on expensive leased multi-protocol label switching (MPLS) circuits.
  • Complete visibility into and control of the WAN


SD-WAN has its own set of distinguishing features:

  • SD-WAN provides software-defined application routing to the WAN.
  • An enterprise’s locations, spread out over a large geographic area (even on a global scale) can be easily and quickly connected using SD-WAN, connecting data centers, remote and mobile users, as well as headquarters and branch offices.
  • SD-WAN programming may be managed by customer or vendor, making it a simpler option for the end user
  • SD-WAN’s focus is on connecting users across a geographic span.
  • SD-WAN is routable through software-defined applications that can be run virtually.
  • SD-WAN is an application-based routing system, rather than a traditional, packet-based network routing system.
  • SD-WAN allows for a centralized application routing governance, while improving both agility and flexibility

Overall, SD-WAN simplifies network management for the end user, allowing IT professionals to focus on other areas of technology management. These SD-WAN basics are a good foundation for understanding the technology.


The SD-WAN opportunity: statistics and predictions

Nothing debunks myths like cold, hard facts. For businesses utilizing SD-WAN or evaluating its implementation, there are a few considerations to keep in mind for the coming year.

  • In light of the fact that cybercrime cost the global economy $450 billion last year, SD-WAN security will grow.
  • Blockchain operations are giving networking tools the ability to “fingerprint” data to improve security. Banks using blockchain could save $12 billion annually.
  • By 2020, SD-WAN providers will handle over half of edge infrastructure refreshes.
  • SD-WAN will be part of a move to managed services wanting a service provider that manages a branch WAN, and SD-WAN helps provide just that.
  • Cloud migration will continue to push the adoption of SD-WAN.



While SD-WAN seems like the wave of the future, many businesses are unsure how it impacts use of MPLS. One of the biggest selling points for SD-WAN is that it can function as a replacement for MPLS. Despite the fact that MPLS is threatened with obsolescence in the face of SD-WAN, there’s actually a business case for keeping both SD-WAN and MPLS together as complementary technologies.

“78% of organizations that have SD-WAN in place won’t be shutting down MPLS operations.”

The combination of SD-WAN and MPLS is not only feasible, it’s also recommended. Here’s why:

  • MPLS has reputation. SD-WAN is a comparatively new technology. It’s certainly got plenty to recommend its use, but at the same time, MPLS is a known quantity and has been for years.
  • SD-WAN is a savings tool. Many will recommend keeping some MPLS as an additional option. SD-WAN does well with reducing MPLS use, which can be a cost-saver for businesses.
  • SD-WAN adds range. While MPLS options were great for large-scale operations, they didn’t always work well for picking up the smaller sub-sites that businesses might have had. SD-WAN, meanwhile, does that job quite well.
  • SD-WAN brings agility. Spin up new sites in days or weeks rather than months with MPLS.
  • SD-WAN and MPLS means reliability. SD-WAN with pure internet links alone isn’t likely to provide the kind of service or guaranteed QoS required by applications. The combination of SD-WAN and MPLS, meanwhile, makes the overall connection more effective and more likely to live up to QoS demands.
  • Clear difference of function. MPLS is commonly seen as a great way to connect two specific points together. But MPLS doesn’t work so well on the global stage or with cloud-heavy users, and there’s SD-WAN’s opportunity.


SD-WAN and network security

Some of SD-WAN’s more distinct characteristics are related to network security. Networks are the area to which there’s been the most change in recent years, so it makes sense that security is more advanced in this realm. Consider these five recommendations for implementing secure SD-WAN:

  • Add encryption to your WAN transport. When you choose SD-WAN, companies have access to low-cost broadband and can encrypt all internet flow to each site without the need for administrators to make manual configuration changes to routers after each change to the network.
  • Many providers offer basic – and some offer next generation – firewall at the branch. Customers may be able to reduce capital expense and management of aging, existing firewalls and replace with SD-WAN appliances.
  • Make sure your cloud connection is secure. Every time you transfer sensitive data over the internet to get to the cloud service, it’s an opportunity for a security breach. All of the inherent risks associated with cloud solutions are mitigated by SD-WAN.
  • Meet compliance requirements. The rules governing healthcare and financial services, including HIPAA or PCI data security, fit perfectly with SD-WAN technology. SD-WAN allows the enterprise to create virtual overlays to segment applications traffic.
  • Create secure segmentation. Segmentation allows the IT team to isolate application traffic for security purposes or to work with specific performance requirements. Segmentation with SD-WAN allows for consistency of configurations and best practices defined and enforced through business intent policies.

With security becoming a growing IT cost, we anticipate more SD-WAN technology to create a secure and manageable cloud-based environment.


Customer problems solved by SD-WAN

  • Are you moving toward adoption of more cloud solutions? Cloud applications like SaaS and IaaS require the intelligent routing provided by SD-WAN. SD-WAN can help you capitalize fully on your investment in cloud-based applications.
  • Is bandwidth performance negatively impacting application users? Businesses that struggle to meet bandwidth demands are good candidates for SD-WAN. The flexible, policy-based traffic routing made possible by SD-WAN can solve many bandwidth problems.
  • Does your network support digital transformation initiatives? Rigid legacy networks often limit business agility. SD-WAN has the efficiency and automation to help businesses innovate and deliver new services rapidly.
  • Can you secure direct internet access? SD-WAN makes it easier to secure your business networks. Attack surfaces can be limited so that if one location falls victim to a breach, it does not affect other branches.
  • Are you increasing the number of remote offices and users? Setting up branch offices is simple with SD-WAN and requires no on-site configuration.
  • Is your business experiencing general connectivity problems? SD-WAN can alleviate headaches caused by dropped calls, slow loading pages, and company websites going offline.


Do you need SD-WAN?

There are a number of ways to tell if your company could use some help from SD-WAN:

  •  Are you migrating workloads to the cloud? Traditional networks are not designed for the demands of cloud utilization. SD-WAN can create dynamic resilient connectivity to wherever the customer, data, or applications live.
  • Are you getting complaints about network quality? Using SD-WAN can leverage multiple WAN links (MPLS, DIA, Broadband, LTE) utilizing load balancing and WAN optimization features to increase network reliability.
  • Are you getting complaints about network cost? Depending on the needs and requirements of the business, MPLS may be removed and replaced with a hybrid (MPLS and internet) or dual internet-based option. SD-WAN can allow for redundant failover WAN connections working in real time.
  • Are you getting complaints about network reliability? One of SD-WAN’s core components is visibility into the network links’ health through a user portal which allows end users to view the health of the network in real time and in historical trends. Another core function is to act in real time on the current state of the network links, making decisions on how to best route traffic.
  • Are you getting complaints about the network holding the business back? If you are actually fighting the network to get applications to perform as expected, it’s a perfect time to talk SD-WAN. Also, SD-WAN helps geographically-distributed offices better connect, and since SD-WAN is very agile, it allows for a fast turn-up of new locations onto the WAN.


Knowing if SD-WAN is a good fit for you is crucial. While the advantages of SD-WAN are obvious to those in the networking house and that is where ASON can help your business evaluate if it is right for you. 


Call us today for a quote.


The ASON Team