With SD-WAN, Don't Forget Performance

With SD-WAN, Don’t Forget Performance

The enterprise WAN has always been challenging to manage. It can be complicated, slow to reconfigure, lack security and many applications perform poorly over it. High service costs, capEx and opEx while performance and manageability remained an issue – a regular lose-lose. But then along came the software defined WAN – the solution to all problems. Or is it?

At a high level, certainly SD-WANs provide some advantages over traditional networks and that’s why the interest has been so high from geographically distributed businesses of all sizes. The problem has become that every vendor that has anything to do with the WAN is now positioning itself as an SD-WAN vendor.

SD-WAN: More Than Just Broadband

From a customer perspective, it’s important to understand that there’s more to SD-WAN than just using broadband as an MPLS alternative or doing some basic form of link aggregation. These things might solve one particular challenge of running a network, such as lowering costs or using bandwidth more efficiently but that only has limited value. In fact, if the performance of applications suffers, then whatever ROI the company was hoping to realize can be tossed out the window, likely with the person’s job who decided that migrating to an SD-WAN was a good idea.

As organizations evolve to an SD-WAN it’s important to keep in mind that performance matters and must be a key consideration point in evaluating any solution. Just because the company migrates to an SD-WAN doesn’t mean that magically all the applications will start to perform better or even on par with the experience users had on a traditional WAN.

Another consideration point is that while the term “broadband WAN” is becoming more commonly used, not all forms of broadband have the same performance characteristics. For example, 4G networks are quick and easy to set up but the connections tend to have high latency and can be expensive. On the other hand, cable is typically very fast but can be congested during peak periods. So it’s critical to understand the various flavors of broadband and the relative pros and cons of each.

Choose your SD-WAN Vendor Carefully

It’s important companies get a handle on this now as business is now becoming network-centric and any disruption in the network will result in a disruption in the operations of the organization. As cloud migration, mobility and IoT become the norm, struggles with performance will become magnified.

However, despite my words of caution, SD-WAN can actually deliver performance that is as good or better than a traditional network if the proper optimization and visibility tools are used. Below are some key consideration points for businesses as they decide on which SD-WAN vendor meets their needs best.

  • Integrated WAN optimization. I know many think that WAN optimization is used only for private network connections but the technology can do a tremendous job of optimizing SD-WAN traffic as well, especially when distance between sites is large.
  • Quality of service. Again, conventional wisdom is that this doesn’t work on a network where the Internet or broadband is used. That line of thinking is wrong; QoS can help any kind of network, including an SD-WAN.
  • Visibility. There’s an axiom that goes “you can’t manage what you can’t see” and this is absolutely true. Having visibility into the end to end network, packet loss, jitter and congestion can help network professionals proactively control applications and the network.
  • Tunnel bonding with stateful failover. Want to use broadband? Go ahead but make sure that the multiple broadband connections looks like a single, larger connection and that packets can dynamically move between paths as the traffic on the network changes. This will help keep user experience levels high.
  • Path conditioning. Some SD-WAN vendors use packet error correction and reordering technologies to “fix” Internet connection weaknesses, making them perform as well or better than traditional leased line services.

The SD-WAN era is here and here to stay. It makes no sense to run a cloud-enabled, mobile organization on a network that was designed for client server computing. However, as companies head down the evolutionary path, it’s critical to keep performance at the forefront.

About the author
Zeus Kerravala
Zeus Kerravala
Zeus Kerravala is the founder and principal analyst with ZK Research. He provides a mix of tactical advice to help his clients in the current business climate and with long term strategic advice. Kerravala provides research and advice to the following constituents: End user IT and network managers, vendors of IT hardware, software and services and the financial community looking to invest in the companies that he covers.