What is SD-WAN

What is SD-WAN? - Why Choose It and How to Get It

Zabrina Doerck
Aug. 21 2019

As you might have noticed, there’s been an explosion of buzzwords lately around the concept of the digitalization of business. Digital Transformation, Intent-Based Networking, App-Centric Infrastructure, User Quality of Experience … all of these terms attempt to articulate a paradigm shift in how businesses design and manage their networks to support the demands on the business in a world where everything lives in the cloud and buyers expect instant access 24x7x365.

Amidst this buzz, all roads eventually lead you to a place where someone tells you that SD-WAN is the magical key to achieving Digital Utopia for your business. And you won’t be alone in wondering if, 1. that’s actually true; and 2. what the heck it means.

The answer to 1, in my opinion, is yes – however, as with most things, it’s not quite that simple. There’s a lot to talk about on this topic, and I plan to address many of these important considerations over the coming weeks, but let’s first start with point 2. And to answer that question, I think it’s good to start with an even more elemental question, which is: What is SD-WAN? And, how did it come to be?

When a company expands beyond a single location, it needs a geographically large network to connect all of those offices or the main office with its datacenters. That network is what we call the WAN. Wide Area Network.

Back in the olden days … like, a few years ago, the WAN was a physical thing with lots of cables and links and boxes that you had to send someone to physically install and configure for every single time there was even a tiny change, update or expansion you wanted to make to the network. And you had no idea what was happening on the WAN from a traffic and performance perspective.

With the emergence of SD-WAN, all of that changed. While the WAN is still very much a physical infrastructure, suddenly we had the ability to manage it digitally, in an automated fashion. Gone were the days we had to send someone to do all the network finagling by hand. But I’m getting ahead of myself. Let’s go back to the basics.

Is SD-WAN really a thing?

The Network World article “SD-WAN: What is it and why you’ll use it one day” includes a few statistics from global research and advisory firm Gartner that can help put SD-WAN’s tremendous growth into perspective:

  • An estimated 25 percent of users will manage their WAN through software by the end of 2019
  • By 2020, SD-WAN is estimated to become a $1.9 billion market
  • Revenue from SD-WAN is increasing at 59 percent each year

In “SD-WAN Adoption: Why Do It and 3 Keys to Make It a Success,” we explored strategies for an effective SD-WAN adoption. Consider the post you’re reading right now a sort of “SD-WAN 101”. I’ll answer the “What is SD-WAN?” question but also share the history of SD-WAN and of the traditional WAN that preceded it, and the value of it for organizations.  

What is SD-WAN?

SD-WAN is an evolution of traditional WAN that offers a more agile networking option for companies. It applies software-defined policies and business intent to WAN connections, enabling IT to manage the WAN through a centralized interface or portal and more strategically direct traffic across the WAN.

Consider a few other ways to describe SD-WAN:

  • An attempt to resolve the network congestion and blocks that can occur with traditional WAN, and transform the network from static to dynamic.
  • A specific application of software-defined networking (SDN) technology applied to WAN connections like broadband internet, 4G, Long-Term Evolution (LTE) or Multiprotocol Label Switching (MPLS), according to the SDxCentral article “What is Software-Defined WAN (or SD-WAN or SDWAN)?”
  • The next logical step to hybrid WAN management, and a way for a company to increase its business agility and flexibility.

What’s the history of WAN?

I’ve answered the “What is SD-WAN?” question, but let’s look at the market conditions that gave rise to it. In the 1970s, WANs supported automated teller machines, credit transaction systems and early online information systems like CompuServe, writes Bradley Mitchell in “What is a Wide Area Network (WAN)?

The technology that ran WANs began with X.25, before making way for the simpler and less expensive Frame Relay. Capable of running at higher speeds, Frame Relay grew popular for telecommunications companies in the U.S. in the 1990s, and, in turn, was usurped in the 2000s by MPLS. It aimed to support normal data traffic as well as voice and video traffic.

Around the time that Frame Relay and the internet caught on, businesses began using leased line WANs, which is essentially a reserved circuit between two points. Some companies opt for hybrid WAN management, which combines connection types to connect geographically separate WANs.

What’s the problem with WAN?

The biggest limitation of WAN is the fact that it wasn’t built for today’s digital world. It’s “poorly suited to the security requirements associated with distributed and cloud-based applications,” said Rohit Mehra, vice president, Network Infrastructure at IDC, in the article “SD-WAN Adoption is Rapidly Increasing in the SD-WAN Market.

Network technology is more than 20 years old and WAN doesn’t address the need for a centrally orchestrated, software-defined WAN edge solution that goes beyond WAN optimization.

Cloud migration is a major disruptor that WAN simply was not built to handle. Adding internet connectivity, cloud and hybrid networking to the mix leads naturally to a consideration of how to best manage all these hybrid networks. Traditional WAN isn’t effective.
The backhaul delay slows application performance and user productivity, a significant problem for companies with digital transformation in mind. That’s especially true in multi-cloud situations.

“SD-WAN is often integrated in a multi-cloud strategy as it improves connectivity and boosts security in the multi-cloud,” according to the SDxCentral article. “Its scalability across numerous locations and its centralized management for both the public and private cloud ease the management of the multi-cloud.”

So how does SD-WAN work?

When talking about the specifics of SD-WAN, it helps to keep a few definitions in mind. These are commonly used concepts when talking about SD-WAN.

  • Software-defined networking (SDN): A networking approach that uses virtualization technology to improve the management and operation of infrastructure (e.g. data center), where “virtualization” means transforming a hardware-based function into a software-based function.
  • Network function virtualization (NFV): A virtualization strategy for transforming groups of network functions into building blocks that can be service-chained together to create communications services.
  • Virtual network function (VNF): A network function that has been virtualized (e.g. a virtualized router, i.e. tele|engine)

SD-WAN extends the capabilities of the WAN using SDN and NFV to create VNFs. Say that three times fast. Or as the SDxCentral article describes it, SD-WAN separates the network from management, and separates the traffic management and monitoring functions from hardware. This requires four things: 1) Edge connectivity abstraction; 2) WAN virtualization; 3) policy-driven, centralized management; and 4) elastic traffic management.

All that’s true. But it’s more enterprise-transforming than that might suggest. SD-WAN is a paradigm shift in how companies think about their network resources.

Now let’s explore what companies do after deciding such a paradigm shift could benefit them.

How do companies buy SD-WAN?

Most companies purchase SD-WAN from either a value-added reseller (VAR), a system integrator (SI), a managed service provider (MSP), a communication services provider (CSP) or through a value-added distributor (VAD). Each of these service provider types offers unique services to customers.

  • SD-WAN Vendor: A vendor, such as Infovista with our Ipanema SD-WAN solution, is the company who builds and supports the actual product itself. They may sell directly to the end user who then manages the solution themselves; they may sell directly to the end user and manage it for them; or they may sell through any of the types of providers/integrators/resellers/distributors listed below.
  • Value-added reseller: VARs, such as CDW Tech Mahindra and Fujitsu, resell SD-WAN solutions packaged with hardware. They don’t necessarily offer a managed service.
  • System integrator/aggregator: SIs and systems aggregators integrate multiple services. Their value is the service integration, consultation, creation and implementation of a complete solution.
  • Managed service provider: MSPs don’t own any infrastructure itself. Instead, they deliver SD-WAN as a managed service to companies. MSPs sometimes resell wholesale connectivity and layer in SD-WAN on top.
  • Communication services provider: CSPs invest in solutions to deliver SD-WAN to clients. Some clients, like telecommunications companies, actually own the connectivity infrastructure.
  • Value-added distributor: VADs pick, pack and ship components for SD-WAN solutions that their customers sell. When we say a VAD is our “sell-through” partner, this is what we’re referring to.

SD-WAN Explained: What’s the value for companies?

The popularity of SD-WAN is soaring but why do companies buy SD-WAN? A webinar called “Top Drivers for SD-WAN Adoption” suggests that four main challenges are driving SD-WAN’s popularity. The findings come from Futuriom’s 2018 “SD-WAN Growth Outlook” report.

Those drivers are: bandwidth demand, especially in the wake of stagnant IT budgets; cloud demand, with more workers relying on cloud applications rather than private servers; a mobile workforce, with people spread across multiple time zones, branch offices and networks; and IT agility, which is a priority for companies who want to agilely respond to market trends, product demands and customer requests.

Synopsis: new business models are driving the need for a new network model.

At its most basic, SD-WAN can provide centralized management, bandwidth management, some cost control, and some networking visibility. Benefits include:

  • Simplified network management. SD-WAN makes it easy to scale across thousands of endpoints, whether they are in the branch, headquarters or cloud.
  • Automation. Centrally configure and push policy changes across the entire WAN from one user interface (UI), eliminating the need for manual updates to each device.
  • Resource optimization. SD-WAN can reduce and/or stabilize network management costs by reducing the need for manual intervention, providing greater troubleshooting capabilities (in some cases), and using bandwidth more intelligently (in some cases). Note that not all SD-WAN solutions are great at delivering these benefits – more on this in a minute. 
  • Improved digital capabilities. SD-WAN expands the universe of possibilities for digital transformation by enabling use of the internet to connect to Software-as-a-Service (SaaS) applications.

With all this said, the extent to which SD-WAN delivers these benefits depends on the quality of the solution itself.  Basic SD-WAN has limitations in how much granularity of control you have over the network, and at the end of day if your solution is not robust enough, you may find that it doesn’t solve for the problems that triggered your business to adopt it.  Plus, who wants a solution that’s merely basic? The true value of SD-WAN is being able to ensure quality of experience (QoE) and quality of service (QoS) for customers using your applications by gaining visibility and control over those apps.

In today’s digital world, user experience (UX) is the face of your company. UX is part of your brand. It’s what you sell, and it’s what your business runs on. To ensure good UX, you must be able to see what happens within your network at the session level. You can’t control what you can’t see.

What’s Infovista’s approach to SD-WAN?

At Infovista, we’re experts in visibility and control, and committed to offering customers deep application insights that can help them increase revenue, improve productivity and avoid huge upgrade costs.

Our solution, Ipanema SD-WAN, is the only SD-WAN with application intelligence that can transform your unpredictable network into a great user experience.

  • Business intent alignment: Do you know which applications are most critical for your business? Ipanema lets you define performance requirements for each application to make sure that the most important apps are prioritized over other traffic, and low priority applications don’t outcompete them for bandwidth.
  • Session-level application control: Define the QoE thresholds you want for your business-critical apps and Ipanema controls each user session automatically and dynamically, regardless of network conditions. That way you can ensure that customers and employees alike always have a seamless user experience of your business critical applications. Or in other words, make sure the apps your business runs on are always on.
  • Comprehensive flexibility: We deploy Ipanema on your terms based on your infrastructure needs. Our solution offers a flexible delivery model that can be deployed as overlay or underlay, through CPE or as a VNF, as a fully routed solution or hybrid, depending on your business needs.

Ipanema SD-WAN goes beyond basic SD-WAN  to ensure the network always serves your business goals.

Case Studies: What kinds of businesses are benefitting from our approach?

Check out a few of our customer case studies to see how Ipanema SD-WAN has helped transform networks.

Group SEB | Dynamic Hybrid WAN Fuels a Global Manufacturing Powerhouse’s Expansion

Manufacturing Customer Profile:

  • Global leader in small appliances
  • Annual turnover of 4.25 billion euros
  • More than 25,800 employees across the globe
  • A presence in over 150 countries
  • Over 200 million products sold a year

Benefits from moving to Ipanema SD-WAN

  • Increased network reliability and ease of operation
  • A hybrid network that meets business QoS requirements while also reducing telecom costs
  • Increased flexibility in terms of migrating the IT system to the cloud
  • Keeping network costs under control

Dixons Carphone | Transforming High-Tech Customer Experience with High-Speed Network

Retail Customer Scenario:

  • Global mobile device retailer
  • Over 2,000 stores worldwide
  • More than 42,000 employees across the globe

Benefits from moving to Ipanema SD-WAN

  • Saved £1.5 Million in network upgrade costs
  • 40% increase in sales conversions
  • 30% increase in customer satisfaction
  • Earned highest Net Promoter Score in industry


We covered a lot. This sums it up

  • What is SD-WAN?

    A solution that applies software-defined policies and business intent to WAN connections, allowing IT to manage through a centralized interface and more strategically direct traffic.

  • History of SD-WAN

    The exact timeline is debatable, but SD-WAN essentially emerged in the early 2010s as a new approach to managing traffic between reliable MPLS and previously unsuitable paths like internet connections.

  • What’s the problem with WAN?

    In short, WAN technologies weren’t built to handle cloud migrations or the security factors that modern businesses face today.

  • How does SD-WAN work?

    SD-WAN’s allow business to completely rethink their network resources, giving network managers the ability to split management capabilities from the hardware.

  • How do companies buy SD-WAN?

    Business have a wide set of options to purchase SD-WANs with the key considerations being the level of in-house control over managing the solution.

  • SD-WAN Explained: What’s the value for companies?

    SD-WAN can lower costs, but the real value is centered around the user experience for your customers and the people that run the business. The experience businesses deliver becomes more digital every single day. SD-WAN is the key to controlling and perfecting that experience.

  • What’s our approach to SD-WAN?

    Our approach to SD-WAN is focused on perfecting digital experiences for your customers and users. That means we go beyond the core functionalities you expect from SD-WAN to deliver powerful tools for visibility and control to have a real impact on user QoE and QoS.

From banking to manufacturing the common denominator driving SD-WAN adoption is its ability to solve business challenges that arise from digital transformation.


To learn why SD-WAN is growing in popularity and strategies for effortless SD-WAN adoption within your organization, read our blog post “SD-WAN Adoption: Why Do It and 3 Keys to Make it a Success.”  And if you’re exploring SD-WAN solutions, learn more about Ipanema SD-WAN. Request a demo today.  


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