SD-WAN Diluted

When a new technology appears, there is a certain period of time before that technology goes mainstream. As many of the vendors and carriers are promising both the end of the traditional WAN and the elimination of the need for network management, it would seem that SD-WAN’s time has arrived. For each SD-WAN solution I come across, I thoroughly research the product offering to see how it fits into our business model and how many customers could benefit from the technology. Claims of “The Branch Router is Dead”, ” Easily Provision a New Site in Minutes”, “Guaranteed QoS”, “Save 50% in Telco costs” and “The End of MPLS” are just some examples of the disappointing and misleading marketing hype I have been reading.

The branch router is a requirement and routing is a requirement of the Internet Protocol (IP). So, while the current state of the router may change, in that it could become a lightweight device with the control plane elsewhere, the need to route still exists.

Provisioning a new site in minutes assumes you have the hardware, or the hardware to support your SD-WAN software on site. In this scenario, there are no tangible time frame differences to provisioning a router in the traditional WAN or SD-WAN method. In either case, networking knowledge and planning are still required.

The next two statements go hand in hand. SD-WAN vendors tout that by removing all of your MPLS circuits and replacing them with more cost effective Internet circuits, you can save 50% in telecommunications costs. Yes, you can do this, but it is important that you know what you are getting into. Since SD-WAN is an overlay, it can create priorities and send the most desirable traffic first. However, if these packets are crossing the Internet they are competing with everything else on the Internet and are not prioritized over other Internet traffic. MPLS has its place and if your traffic requires real QoS, then MPLS is still the best way to deliver that.

So, back to my title, SD-WAN Diluted. When SD-WAN first emerged, it was about Centralized Control, Quality of Service, Predictable Application Delivery and Optimized Bandwidth Control. The benefits of true SD-WAN have been diluted down to promises of cost savings that either do not exist or are not feasible given the critical role that network infrastructures play in a vast majority of corporate environments.  This technology has a lot of potential and will change the way we deploy and manage networks. Not for all of the reasons listed above, but because it will make better use of the existing resources.