What Is SD-WAN Technology?

If you were driving in an unfamiliar city and wanted the most efficient route possible to your destination, you might use Google Maps to navigate your way. Or, you could use the Waze application to get there. But wouldn’t it be better if you just had both running simultaneously, and whichever one gave you the best route would be the one that automatically navigated your car?

That’s the promise, in a nutshell, of software-defined wide area networking, or SD-WAN, technology. Although it’s still an emerging network technology, it’s becoming more mainstream because businesses of all sizes, and especially small and medium-sized businesses (SMBs), are recognizing that it is a more efficient and cost-effective way of deploying and managing networks than legacy technology.

SD-WAN adoption is rising because this approach makes network management more agile and less costly. It is agnostic with regard to the network transport technology (multiprotocol label switching, mobile, broadband) and enables prioritization of mission-critical applications. SD-WAN also makes it easier to provision and manage networks at branch locations, which is especially helpful for companies with numerous branches, such as a bank, restaurant chain or clothing retailer.

IDC estimated in July 2017 that worldwide SD-WAN infrastructure and services revenues would grow at a compound annual growth rate of 69.6 percent and reach $8.05 billion in 2021. Meanwhile, Gartner has predicted that by 2020, more than 50 percent of WAN edge infrastructure refresh initiatives will be based on SD-WAN compared to traditional routers.

Here is a primer on SD-WAN, the benefits of deploying the technology and how it is being used in real-world environments:

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What Is SD-WAN Technology?

SD-WAN applies software-defined networking (SDN) concepts to wide area networks, and decouples the network and the control plane, abstracting traffic management and monitoring from network hardware. The technology then applies that to individual applications running over the WAN. It boils down to the “idea of using two circuits concurrently in a smart way,” as Daghan Altas, senior director of product management at Cisco Meraki, explained at a CDW conference in September. That means a router, firewall or another SD-WAN device “can essentially choose the best path for the best application.”

For example, voice calls and credit card transactions can go over MPLS switching while YouTube uses a broadband connection. SD-WAN lets companies set policies so that the network can do that automatically, Altas said, “so that the IT people don’t even have to know it. They can set it and forget it.”

By automating network deployment and management, both SDN and SD-WAN virtualize resources, which boosts performance, enhances the efficiency of the network and improves network availability while lowering total cost of ownership.

How Does SD-WAN Work?

Traditional WANs help companies support their business-critical apps, including virtual desktops, Voice over IP and videoconferencing platforms, enterprise resource planning and other critical apps, Citrix notes in a blog post. These often take up a lot of network bandwidth and require high reliability and quality of service.

In the past, businesses would handle this by installing proprietary or specialized WAN technology and increasing network bandwidth. However, that can be expensive and doesn’t help the company actually prioritize the mission-critical apps, many of which are increasingly located in cloud environments.

SD-WAN allows businesses to create hybrid WAN architectures that use multiple kinds of connections — different paths, essentially — to automatically create the best network path for the apps running on the network. It enables certain apps to be prioritized over other, less important network traffic. This can be done at a granular level and managed via a centralized software controller.

What Are the Benefits of SD-WAN for Your Business?

SD-WAN offers numerous benefits for organizations of all sizes but is especially helpful to businesses with branch locations. The software that sits at the heart of SD-WAN allows IT staff members to remotely program edge devices and significantly cut down on provisioning time. This reduces and, in some cases, may eliminate the need to manually configure traditional routers at branch locations, as TechTarget notes.

“If an SMB has a number of remote branches that are critical to the success of the business, runs critical applications and services at those remote sites, and has a need to tap into a more cost-efficient way to access bandwidth, there’s a compelling case for SD-WAN,” Brad Casemore, an IDC research director, says in a BizTech article on SD-WAN adoption.

In general, businesses are adopting SD-WANs to improve performance for all apps, including those that reside in the cloud, and to better manage WAN capital expenditures and operating expenditures, according to Gartner.

IT industry analyst Zeus Kerravala, writing on the website No Jitter, notes that businesses can cut costs by replacing, or at least augmenting, high-cost MPLS networks with much lower-cost broadband internet connections. MPLS can be used for mission-critical traffic and general-purpose traffic can be sent down regular internet connections, which saves money.

Beyond those cost savings, Kerravala argues that SD-WANs help maintain application performance because they can be configured to not only protect against network failures “but also dynamically change paths when application performance degrades.”

“If you’re not looking into SD-WAN, if you have lots of locations, you should,” Altas said at the conference. “It will give you reliability, it will give you cost savings, and it will give you more bandwidth. You get two out of three.”

To achieve two of those three goals, Altas explained that the company must be willing to sacrifice the other. “If you put more circuits in, then obviously you are not going to get cost savings,” he said.

But by moving to a dual-broadband solution, companies can save money and increase their network bandwidth, Altas added. However, the company is then taking a gamble on reliability by not having any MPLS solutions in the mix. “If I’m a retailer or hotel, I would take that risk,” he added. “But if I’m a bank, I might not.”

Which Companies Are Already Using SD-WAN Technology?

There are numerous vendors that have deployed SD-WAN solutions, including Cisco Meraki, Citrix with its NetScaler solution, Riverbed, Silver Peak and VeloCloud (which was acquired by VMware in November).

More numerous are examples of businesses making use of SD-WAN right now.

Milwaukee-based Briggs & Stratton is the world’s largest producer of gasoline engines for outdoor power equipment, as well as a leading designer and manufacturer of, among other products, lawn and garden and job site equipment. Last year, Briggs & Stratton rolled out Cisco Systems’ Intelligent WAN to 45 sites scattered around the world. The software-defined IWAN lets the company deliver more functionality to remote locations for the same or lower cost than was previously possible.

“We’re a global company and need the most secure, reliable and cost-effective way to distribute information and resources we can find,” IT Director Norm Mackensen tells BizTech. “With IWAN, we have increased visibility into the network and added security without adding cost. And because Cisco is also an industry standard, our management partners all over the world are familiar with its technology.”

SD-WAN isn’t just for corporate giants though. Small businesses are also deploying SD-WAN and seeing significant benefits. By spring 2017, Salon Service Group, a professional hair products distributor based in Springfield, Mo., was supporting 30 stores in 11 states and needed a way to integrate its increasingly complicated network, Chris Rushton, SSG project director, tells BizTech.

The company undertook a staged rollout of a cloud-delivered SD-WAN from VeloCloud, which it completed last fall. The deployment has resulted in more control, visibility and security for the SSG network, along with cost savings, she says.

“We were dealing with long-distance calling to stores, billing from many carrier sources and data that was insecure, incomplete and that we had no control over,” Rushton says. “Since we’ve started using VeloCloud, billing is under control. I can now log in to all locations and see and manage that part of the network.”

SD-WAN gives businesses more control, flexibility, reliability and lower costs. It’s no wonder, then, that it seems to be the wave of the future.