Top Five Questions to Ask when Considering SD-WAN

By Louise Fouracre, Business Development Manager, Wide Area Networks

As a trusted WAN service provider for many years, Zayo is the expert in all things WAN. So when I was asked to represent Zayo as a panelist at this year’s WAN Summit in New York City, I welcomed the chance to talk about what sets us apart in a highly competitive industry. Telecom has changed quite a bit since I was hired as one of the first female system engineers in the 1990s, but WANs have remained relatively unchanged until the recent introduction of SD-WAN. Zayo began our SD-WAN journey in January 2018 and now has deployments stretching from the United States up into Canada and across the Atlantic into Europe.

The panel at the summit included carriers, customers and hardware manufacturers discussing proof of concept (POC) to pilot and roll-out. As we sat on stage, listening and responding to questions, we found ourselves at the center of something exciting and innovative: after years of relative consistency, we are now experiencing the rapid evolution of WAN.

Zayo’s Business Development Manager, Louise Fouracre (far right), with other members of the panel discussion, “Letters From the SD-WAN Frontier – From POC to Pilot & Roll Out” at the WAN Summit in New York City, April 2019.

So much of what was discussed at the WAN Summit is important to enabling opportunities for growth and success for enterprises and entrepreneurs. Based on the conversations and ideas discussed, here are the five most important questions to ask when considering SD-WAN:

1. What is the motivation for pursuing SD-WAN?

Unlike MPLS, which has been used in wide-area networking for the past two decades, SD-WAN is access agnostic and enables fundamentally different network choices. Customers can now use the best network access at the best price. MPLS can be augmented with Dedicated Internet Access (DIA), and can even bond different access types (DSL, DIA, and/or LTE) to create one large pipe. At Zayo, we offer access combinations that provide the customer up to 100% uptime. This is further proof of how SD-WAN gives customers options and flexibility in creating a WAN that simply did not exist a short time ago.

2. How does SD-WAN help drive business?

  • Cost/Speed to install: SD-WAN allows customers to choose the best cost option for each site. Setting up a remote site now happens in a matter of weeks with LTE or broadband, not months.
  • Failover/Redundancy: As more and more applications move to the cloud, having WAN outages is not acceptable. All customers, not just large organizations, can add an inexpensive secondary circuit for failover.
  • Application-Aware: Customers can prioritize which applications are the most important to them and have corrective actions happen automatically in the event of network degradation.
  • Network Control: Customers can see their entire network on a single pane of glass, quickly view all access circuits, and drill down into each site to see how the circuits are performing (real-time information, historical information, or both). This allows customers to see which applications are using the bandwidth and write policies for those applications.

3. What are the best practices for building an SD-WAN proof of concept (POC)?

Like all proof of concepts, proper planning and preparation are key. While each company’s environment will be different, here are four areas to review and some examples of questions to ask and information to gather.


  • What is the current WAN topology?
  • What SD-WAN topology do you want to have? What are the underlays/access that will be tested (DIA, MPLS, LTE, and/or Broadband)? Do you want fail-over(Active/Active, Active/Standby)? Will you require high availability for the hardware as well?


  • From a QoS perspective, what classes or service / DSCP do you need prioritized and with protected bandwidth?
  • What applications are critical for your business that can be used to demonstrate application traffic steering and SLA thresholds?


  • What is the existing firewall vendor/product?


  • Are there certain features that you would like to see when looking at monitoring and analytics in the portal?
  • Are there certain applications for which you would like to establish service level agreements/traffic steering?

Zayo offers a white glove service for our SD-WAN proof of concept service. We work with the customer to pre-configure the customer-premise equipment (CPE) and software. Zayo will be on-site to deliver the CPE and get it up and running to ensure the customer can log into the portal, gather reports and understand the overall health of their SD-WAN.

4. What is the scope of an SD-WAN implementation? How should WAN managers time the transition?

All SD-WAN deployments included in a proof of concept (POC) will be project managed by experienced Service Delivery Coordinators.  As an overlay technology, the timing of an SD-WAN deployment is dependent upon the underlying transport used. For example, delivery timeframes for POCs using existing DIA will be much shorter than ones requiring new circuits. Contact us directly for customized implementation estimates.

5. Most enterprises plan to keep MPLS, so how do they calibrate their MPLS exposure?

A recent IDG Market Pulse Survey showed that when it comes to SD-WAN, 80 percent of enterprises are choosing to build upon their existing network infrastructure, rather than replace.

MPLS is still a great WAN technology and provides a reliable network with quality of service. We see customers wanting to keep their current reliability and augment with other forms of access to create a larger access pipe for an “always-on” environment (active/active) or act as a fail-over.

While a lot has changed since the 1990s, one thing that has not changed is the need for a reliable WAN. When you are ready to evolve your WAN, consider leveraging Zayo as the fiber backbone for all your enterprise networks. We look forward to connecting with you. Learn more»

Louise Fouracre is the business development manager for Wide Area Networks at Zayo and has more than 20 years of telecom experience. During the tech boom in the late 1990s, Louise pioneered the way for women in technology by becoming the first female systems engineer hired by Redback Networks, a company acquired by Ericsson in 2006. She furthered her industry expertise at AT&T and Dell until her entrepreneurial spirit led her to found her own successful SaaS and IaaS company. Louise received her Bachelor of Science in Business Administration, Master of International Management and Master of Telecommunications degrees from the University of Denver.