If you’re considering implementing software-defined WAN (SD-WAN) in your business, you'll want to make sure it's the right move. Assessing whether or not your customers really need SD-WAN is an important step.

A good place to start is with a self-assessment. The following questions will help guide you towards understanding whether SD-WAN is the right communications architecture approach for your organisation and your customers.

1. Do you plan to increase the number of cloud apps or services you use?

Increasing cloud-based apps will impact traffic patterns. SD-WAN can securely direct a portion of your traffic from the branch to go straight to the cloud via public internet links, giving a better user experience if you don’t have many resource-hungry apps at the branch.

Consider how cloud-based apps may impact the implementation of SD-WAN in your business.

However, SD-WAN may not be ideal for the following reasons:

  • You have large numbers of branch offices, as SD-WAN products are optimised for fewer than 200 users
  • Your WAN is mainly single-homed locations, which means you lose the benefits of dynamic path selection and application-centric routing
  • High latency WAN which degrades application performance, as many SD-WAN products do not include WAN optimisation.

2. Do you have remote users affected by bandwidth issues?


It’s difficult to ramp-up bandwidth with traditional communications architectures such as MPLS. SD-WAN solves this by letting you flexibly manage traffic routing based on business policy. Path control can be automated, and path quality determined by available bandwidth, latency, jitter, or packet loss.

3. Do you need to support a digital transformation project/customer experience?


Unlike traditional WAN technologies, SD-WAN decouples the network and control plane and utilises a software-defined approach, making it easier to adapt to the changing demands of application delivery and business requirements. SD-WAN includes integrated monitoring across the network to improve the overall digital experience.

4. Do you need to improve the security of direct internet access?

You may need to consider cyber security protocols before implementing SD-WAN.

SD-WAN allows you to limit network attack surfaces that prevents a breach at one branch affecting others. You can secure your public and private connections using embedded firewalls and VPNs, while network segmentation can let you select traffic paths for each application and type of data depending on business priority and security needs.

5. Is your organisation growing?


SD-WAN lets you set up new branch offices easily and cheaply as it requires no travel or on-site configuration. Using SD-WAN, you can bring appliances online automatically by using centralised policy rules. You can also automate cloud connectivity and deliver unified cloud policy across regions cloud service providers.

Moving forward with SD-WAN

Now that you have determined whether SD-WAN suits your organisation’s needs, the next step is to evaluate products and providers. The following is a sample of Gartner’s Toolkit: RFT Template for SD-WAN Products and Services suggested questions to consider. This template will help you create a decision map to make the right choice for your application.

  • What is your scale and architecture? (i.e. minimum and maximum number of remote branches) Consider network-based infrastructure (points of presence) and where and how you will host and connect the points of presence. Consider how resiliency is achieved and how you will support direct internet access
  • How is management and orchestration capability delivered?
  • Consider your form factors for branch components and deployment options. For example, can they be delivered via physical appliance and/or software? Is the vendor's software available in leading public cloud provider catalogues?
  • What is your application centricity? For example, how does the solution support cloud-based applications? Does the enterprise have to create its own gateways or hubs, or is the solution integrated into cloud services (both infrastructure as a service [IaaS] and SaaS)?
  • What are your price constraints? Consider three- and five-year total costs for installation, hardware, software, licensing, service, and support. What level of visibility and security is available?

What to read next:

The rise of software-defined networks
What is SD-WAN and why will you use it someday?
The benefits of moving from CapEx to OpEx for IT spending