SD-WAN – The Smart WAN is Here!

June 3, 2019 Technology

SD WAN By now many of you have probably heard about SD-WAN – the technology that promises improved user experience by virtue of intelligent path selection combined with application recognition and visibility. If you haven’t, let me give you a brief analogy.

Imagine that you are traveling down the highway and suddenly you hit traffic. Not just light traffic, but complete gridlock. To make matters worse there are no exits in sight. Great, you are already late to your big meeting and the universe is conspiring against you. You look to your left and see a different part of the highway with very little traffic flowing in your same direction and wonder: how can I move to those lanes? Can I open some magical wormhole that can take me out of this mess? In networking terms, SD-WAN is that magical wormhole. Instead of waiting for the authorities to somehow re-route traffic, a new path is quickly paved for you. Now imagine that the same wormhole instantaneously opens up for everyone that is going to your same destination. Wouldn’t that be awesome? Everyone will be on time for the meeting. SD-WAN is a revolutionary new technology that allows us to make quick routing decisions based on pre-defined conditions – like a common destination application.

So why do we need SD-WAN?

Simply because the conventional way of making routing decisions and categorizing traffic just doesn’t meet today’s high-performance demands. The network needs to be more agile and intelligent in order to ensure a better user experience. And though you can use conventional methods to provide some level of automation, these types of configurations can consume a substantial amount of time while being developed and are often less than perfect due to the need for manual intervention whenever the environment changes. These limitations often mean that you have to keep an active and a standby path leaving bandwidth unused – and CIOs with a lot of questions for you. The network needs to be less about packets and more about applications.

With the rise of cloud-based applications, the traditional combination of destination IP address and port number commonly used to identify network traffic has become less effective. Many cloud application providers use different data centers in geographically dispersed regions expanding a wide range of IP addresses and port numbers that can change at any time. More so, since a lot of applications are being delivered through port 80 and 443 (common TCP ports), identifying them has become even more difficult. Add the adoption of encryption for just about every connection and you have drastically increased complexity.

Problem solving with SD-WAN

To overcome these challenges, SD-WAN solutions employ layer 7 application recognition, deep packet inspection and traffic signatures – among other technologies – to quickly identify applications. This level of awareness gives this technology the ability to easily steer traffic and enforce policies based on user defined thresholds. The connection is dropping packets? You can have the system flip the traffic to a secondary link, no problem. The application is experiencing higher than expected latency? Switch it over to a better performing connection. All of this could be done on the fly and without the need to deal with complex per-device configuration changes. Of course, this sorcery can only happen if you have at least 2 paths available. But think about the freedom this could bring to your WAN deployment. You can now spend your time yelling at the provider whose circuit has been down for 2 hours while your customers continue on with their daily tasks. It could also give you more flexibility when choosing providers since you can mix WAN technologies (MPLS, Ethernet, etc.) with a variety of Internet connections (Cable, DSL, FiOS, etc.). You can get rid of non-critical Internet traffic more efficiently avoiding unnecessary backhaul to a centralized connection, and even keep site-to-site VPNs always on as failover to your private circuits. More importantly, you can show your CIO how your data circuits are now being fully utilized thanks to your “wormhole” technology.


SD WAN Miguel

Miguel has worked in the IT industry for the last 22 years. He spent 14 of those years in Healthcare IT at Bon Secours Health System. Miguel joined our team in 2019 as a Solutions Architect in our Virginia Beach Office. He has experience in virtualization, storage networks, routing and switching, wireless, and more; but networking is his self-proclaimed forte. Outside of work, Miguel enjoys playing his guitars and spending time with his kids.