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SD-WAN: What it is and why you’ll use it one day
An SDN for your branch office
Managing the Wide Area Network (WAN) for Redmond Inc., a supplier of industrial and commercial products – from salt that’s used to protect winter roadways to organic dairy products and health items – is an easier job today for the company’s technical project manager Aaron Gabrielson than it was a year ago.
Redmond manages a phone system, point of sale and fax centrally out of headquarters in Heber City, Utah, which means each of Redmond’s 10 branch sites across the Midwest need a reliable connection back to headquarters in Utah. That’s easier for some sites, like those in Salt Lake City, than others, such as rural areas where there may only be a handful of workers on a farm.
It was here that a software-defined WAN (SD-WAN) came to the rescue. Gartner estimates that SD-WAN has less than 1% market share today, but it predicts that up to 30% of users will be managing their WAN through software within three years. Redmond is an early adopter.
One of the chief characteristics of an SD-WAN is its ability to manage multiple types of connections – from MPLS to broadband to LTE. For Redmond, that’s been hugely helpful.
Gabrielson buys cheap commercial-grade Internet connections at his rural branch sites. The SD-WAN program from VeloCloud aggregates at least two links together to create a single bundled link that’s stronger than either one individually. It provides rural sites with enough bandwidth to use voice over IP (VoIP) and process credit card transactions.
SD-WAN can be thought of as a little brother to its more well-known sibling software-defined networking (SDN). They’re related – both software-defined, but whereas SDN is meant for internal data centers at a campus or headquarter location, SD-WAN takes those similar software-defined concepts and the decoupling of the control plane from the data plane to the WAN. “SDN is an architecture, where as SD-WAN is a technology you can buy,” explains Gartner analyst Andrew Lerner, who tracks the SD-WAN market closely.