SD-WAN has fundamentally changed network management for organizations that don’t have the resources needed in today's environment, according to Expereo Director of Global Solutions Engineering Salim Khouri. Before SD-WAN, key tools like virtual private networks (VPNs), firewalls, and MPLS were hard to scale, hard to use, and needed specialized individuals to oversee them. 

“SD-WAN made the WAN equation, or the WAN side of the network, much easier and accessible, especially for IT teams,” Khouri told SDxCentral. 

[caption id="attachment_120436" align="alignleft" width="250"] Expereo Director of Global Solutions Engineering Salim Khouri[/caption]

“Now it's become this nice framework and it's matured quite a bit, even in the last few years there are some key players that have become quite dominant because they've democratized, in a way, complex deployments that were previously much harder." 

But Khouri added there is a “gotcha” to the democratization of SD-WAN. 

Initially, SD-WAN was marketed as an easy-to-deploy solution where all that was needed was to “plug in two commodity internet circuits, and get rid of that expensive MPLS.” While this simplified operations for smaller, regional networks, and those located in “top cities in the world,” Khouri said the rush to move away from MPLS wasn’t well judged for others. 

“If you have the direct line to the CEO of every telco provider, it's a great experience,” he explained. “But if you are not that, and you're like everyone else, where you have shortage of IT staff globally, or you're getting internet connections from local suppliers, you don't really know how good their infrastructure is to carry that data, and all of these little details that --  if you listen to the manufacturers, they said no, no, we'll solve all these problems for you, just plug in the box -- you realize that it's not so simple.”

These cases, or what Khouri calls the “do it yourself market,” is where he sees the SD-WAN gotcha.

“People realize, wow, it's not so easy to deploy a box,” Khouri said. 

Khouri said many of the problems that SD-WAN presented when it first emerged led to “a lot of lessons learned, especially with a lot of companies out there that wanted to do it themselves and realized, you know what, I don't want that headache.” The industry is also starting to see which use cases the SD-WAN framework fits into, and which it doesn’t.

While SD-WAN market growth is on track to hit high analyst expectations, MPLS is maintaining relevance in some industry corners. 

Market research and consulting firm TeleGeography’s latest “WAN Market Size Report” found that MPLS is still worth $17 billion, or 29% of the global WAN market, and local loops connecting customer sites to direct internet access are worth $3.8 billion. Together, MPLS and access loops connecting to MPLS PoPs maintain 60% of the market for large multinational enterprise WANs. 

"You’re gonna see them stick with MPLS in a lot of other places like in the developing world or just less competitive markets where there’s not a robust suite of ISPs.” TeleGeography Senior Manager Greg Bryan told SDxCentral in an earlier interview, adding that MPLS will stick around even in developed markets because companies aren’t willing to jump into the internet.

While Bryan conceded the MPLS market is “certainly diminishing,” it’s unlikely to disappear entirely. 

Added Khouri, “If I am in a small geographic region and it's very infrastructure rich, meaning I can get fiber connectivity everywhere, you can get very cheap MPLS. There's always a specific use case. And this is where I think the death knell of MPLS was overblown. In some markets, it doesn't even make sense to get out of it.”