What is SD-WAN and Why Should You Care?

Your deadline is coming up and you’re working feverishly to finish a project, when the Internet dies. Okay, the Internet didn’t really die, but the backhoe operator that just cut through your only connection to the Internet certainly makes it seem that way. Commence PANIC.

One way to avoid that scenario, and any other that disrupts your required feed of the magic that is the Internet, is to use more than one WAN connection. Running an extra WAN connection to your firewall isn’t going to be enough though. See, the biggest problem with using two WAN connections is that you have two different sets of public-facing IP addresses. This is why standard firewalls can failover outbound traffic, which doesn’t care where a web request for an IP originated, but can’t do anything for inbound traffic (e.g. Web and Email Servers, Remote Access), which is looking for a specific IP. Those items will potentially no longer work, depending on which WAN connection went dark. There are things you can do with DNS to mitigate some of those issues, but that’s outside the scope of this article.

This is where a service called SD-WAN steps in to save the day. While there are different variations of the service, I’ll be focusing specifically on “premise-based SD-WAN.” Premise-based SD-WAN involves an on-site router and a cloud-based service provider. Two WAN connections of your choosing are fed into the router, which then connects to your firewall. A quick change of your firewall settings to use the new IP address(es) provided by the SD-WAN service, and you’re ready to go. The great thing is that your choice of WAN connections is wide open, and you can mix and match to fit the needs of your budget and bandwidth requirements. Many of our clients go with a business-class cable connection and a fiber connection, but you can also mix in wireless or DSL if those are available. The only real recommendation is that the source for each connection come from a different ISP, or that each connects to a different Internet backbone.

The SD-WAN service aggregates the two WAN links which provides automatic failover, increased bandwidth, reduced jitter for VoIP applications, and QoS benefits. In the event one of the connections goes down, your business will continue to operate as if nothing had happened, aside from a decrease in available bandwidth. Monitoring, alerts, and monthly reports all combine to give you insight into the service and how it is helping your business stay productive.

So in the future, there’s no need to get nervous when they’re tearing up the street outside your business, as your Internet connection is protected. Your water supply on the other hand—that’s a different story.

Interested in setting up an SD-WAN for your business? Contact one of our network consultants today to learn more!

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