The Speedy Evolution of SD-WANs

Virtualization is a potent concept that gets applied in many ways. The basic idea is that software is so sophisticated and networks so fast that complex computing no longer has to be done where it is used.

A foundational change that flows from this is software-defined networks (SDN). An implementation of this is in the world of wide-area networks (WANs), which are network overlays that enable widely diverse entities – for instance, branch offices in different cities or on different continents – to logically act as a single entity. This provides great cost savings and greater efficiencies.

Combining SDNs and WANs creates what unsurprisingly are called Software-Defined Wide-Area Networks (SD-WANs). SD-WANs are evolving quickly because they fill a need.

“The reason why SD-WAN is really popular is that it is not just a technology trying to find a solution,” said Ralph Santitoro, who is the head of SDN/NFV/SD-WAN Services for Fujitsu and a Distinguished Fellow on the MEF Board of Directors. “It solves a real business problem.”

Quarterbacking MPLS and Broadband

These are heady days for SD-WAN – and more good times are ahead, according to Brad Casemore, IDC’s research director for Datacenter Networks.

“The growth prospects for SD-WAN are robust,” he wrote in response to questions from IT Business Edge. “We’re seeing strong demand in the market this year, to be followed by even greater demand going forward.”

Legacy WANs feature a protocol called Multiprotocol Label Switching (MPLS) for distribution between, for instance, headquarters in St. Paul, a branch office in Fresno, California, and a factory in Lynchburg, Virginia. MPLS is pricey. But, until SD-WANs came along, it was the best option. The expense of MPLS is justified if what is being transferred is the gross sales for the day or other mission-critical and sensitive data. It isn’t if the content is the final standings of the company softball league.

SD-WAN solves this challenge by enabling the less demanding data to be transported by less expensive broadband. SD-WANs agilely segregate data so that sales receipts still get MPLS treatment — while the details of how the accounting department victory over the shipping department are sent over far cheaper broadband connections.

There is a related benefit. Traditional WANs are routed through data centers because that’s where data and applications historically are stored. Many corporate functions are migrating to the cloud, however. SD-WANs are not burdened by this legacy topography and can connect remote users directly to those assets.

The Carriers Jump In

The number of SD-WAN providers who have jumped into the mix during the past couple of years suggests that the ecosystem – from venture capitalists to equipment makers – is sold on the idea.

It all sounds great, but end users must take care.

“A major challenge is sifting through the marketing-speak to find the technical solutions that meet your needs with a stable software platform,” wrote Steve Garson, the president of SD-WAN Experts.

“Some vendors are selling features that are on their future roadmap and not available today. Some are selling features that don’t exist today, and they don’t share that with the customer. Add to that the companies that may not exist in two or three years. We have inside access to the leading service providers to help avoid decisions based on vaporware.”

Carriers increasingly are becoming the go-to source of SD-WAN connectivity. Many enterprises don’t really want to be in the SD-WAN business. The core technology, which includes load balancers, security and other elements, is complex. There are also management challenges. SD-WAN involves managing multiple contractual relationships. An organization with facilities in several cities will rely on more than one carrier. SD-WANs can be intimidating to enterprises and more or less are a non-starter for small- and medium-sized firms.

One such provider is CenturyLink. A year ago, the company unveiled its first SD-WAN service. It expanded its offering with the introduction of a managed hybrid platform in July. The platform, said Troy Trenchard, the carrier’s vice president for Product Management, integrates broadband and MPLS services.

CenturyLink believed enough in the SD-WAN approach to expand its offering.

“I think it’s early but it’s starting to be proven,” he told IT Business Edge. “We’ve had success and very happy customers. But it’s early. If you look at enterprise customers, they are interested in fulfilling certain needs in their environments — but they are not ready to replace their whole network with SD-WAN. They are learning about it and using it where it makes sense today. They probably will use more of it over time.”

The move to SD-WANs has gained momentum during the past year. During the next year or so, it is likely that the market will begin consolidating. It is clear, however, that the basic concept will establish itself more fully.

IDC’s Casemore sees a bright future for SD-WAN: “SD-WAN is evolving from being an early adopter market, where the first customers were relatively technologically sophisticated and tended to embrace DIY solutions, to a market that is moving to engage with early mainstream and mainstream enterprise customers,” he wrote. “[These customers] are more inclined to seek out turnkey solutions, often from MSPs and CSPs. This is a natural market evolution, where ease of consumption, deployment, and management assumes greater importance as the market ramps.”

Carl Weinschenk covers telecom for IT Business Edge. He writes about wireless technology, disaster recovery/business continuity, cellular services, the Internet of Things, machine-to-machine communications and other emerging technologies and platforms. He also covers net neutrality and related regulatory issues. Weinschenk has written about the phone companies, cable operators and related companies for decades and is senior editor of Broadband Technology Report. He can be reached at cweinsch@optonline.net and via twitter at @DailyMusicBrk.