Why you need MPLS and SD WAN 

Published: April 1, 2019

Some network vendors have been marketing SD WAN as the ultimate solution to any network issue. They’re selling SD WAN as a revolutionary box that allows you to throw away your traditional MPLS network, with a claim that you will dramatically reduce your operating expenses.

There’s a kernel of truth in there: SD WAN does let you use less expensive connections for some business applications. But in most circumstances, you’re not going to jettison all of your MPLS connections once you switch to SD WAN. 

Instead, SD WAN works on top of your MPLS and broadband connections to improve performance and control costs. Without a robust connection to work with, however, SD WAN may not be able to provide the uptime and reliability you need to run critical enterprise applications.

SD WAN vs. MPLS: Complementary Connectivity 

MPLS or multiprotocol label switching refers to a type of connection you use to create a network. You’ve got public connectivity and private connectivity and MPLS is used over private connections in order to prioritize traffic based on its type, where it’s going and on its priority. 

SD WAN is an overlay that’s defined by software. It sits overtop both MPLS and internet connections. You can take any number of different connection types and put SD WAN service overtop of those to manage traffic flow. That combination of connection types depends on your application environment and business objectives.

When you’re connecting large data centers together, you’re not going to use broadband, which only offers best effort. You’ll need to use a big, powerful connection with reliable service levels — MPLS. Chances are, that’s something you already have. SD WAN will take your existing infrastructure and help it run more efficiently, but it’s not going to replace it outright, especially if you’ve got bandwidth-hungry applications that require a big pipe. 

SD WAN allows you to route mission-critical apps along that big pipe, while certain lower-priority apps (like a chat or email) can travel over the public internet. The result? The ability to reduce some of your MPLS costs, but not all of them. 

There’s one key question you need to answer about your network: do you have the right combination of connectivity and traffic management to deliver optimal application performance? MPLS is part of the connectivity component. SD WAN manages the traffic. Ultimately, it’s not especially useful to compare SD WAN versus MPLS one-to-one—they’re complementary technologies: that is, one is not a replacement for the other. And more importantly, one is not going to kill the other.

Finding the right mix

Whether you’re part of a large financial institution, a media company that delivers video, or in the manufacturing sector, you need to deliver a high quality of service along with top-notch security. Doing all that over broadband isn’t going to cut it. You’ll need a robust and resilient network. 

That means having the right mix of MPLS connections (for high-bandwidth priority applications) and broadband (for lower-priority applications), along with a smart way to direct your traffic. 

That’s what SD WAN does, and why it won’t replace MPLS anytime soon. 

Learn more about Verizon’s Managed SD WAN.