SD-WAN is one of those buzzwords that is being used left and right but what is it exactly?
SD-WAN stands for software-defined WAN and its considered part of the always growing software-defined networks (SDN) environment. Think of it as an application managing your WAN links to connect to each of the branches or locations on your enterprise to each other. In the cisco world this can be compared with the AutoVPN feature that some routers have.
To put it on layman terms for an IT professional, an SD-WAN device is a box you plug all of your WAN links handed to you by your ISP to create an encrypted tunnel to another branch that has another SD-WAN device.
Isn’t that what a router do, you might ask and the answer to this is yes and no. Routers (without getting into technical details) were made to just route traffic using one path or the other and unless you go through some headaches to try configuring load balancing you will still need to send the private traffic in a different path than the public one.
SD-WAN devices allow you to use both paths at the same time so you can fully utilize both circuits. You can even have only public paths to the internet and the device will be able to still use them to send the traffic across to the other branch without compromising the data using encryption. Isn’t that cool?
So why wouldn’t every company out there use this instead of paying big bucks for all these private circuits… well you probably already guess it. Because the traffic needs to be encrypted and encrypted at both ends sometimes the throughput doesn’t match the company requirements. Traffic going through a broadband connection can’t be guaranteed so if you have applications that are sensitive to latency and use tons of bandwidth it will be a little more challenging tweeking the appliance to perform the way desired.
In my opinion, the benefits are far worth it if you are going to implement the solution in a multi-branch enterprise that requires connectivity between them. I’ve had good experience with Talari and Meraki SD-WAN solutions but can’t say the same thing about Citrix and its netscaler offering (even though they licensed the technology from Talari).