Tutorial Introduction to SD-WAN

SD-WAN concepts and features are easier to explain with visuals than solely in text. Therefore, I created a short tutorial video introducing them, particularly as they pertain to carriers/service providers. In this tutorial introduction to SD-WAN video, I highlight the near-term coexistence of SD-WAN and MPLS. There is further commentary on the topic below the video. If you want to see what leading U.S. carriers are doing with their specific SD-WAN deployments, visit the page on this topic. If you’re not familiar with Software Defined Networking in general and need a primer, you can check out my tutorial video on that subject.

(…adjust video quality with the Settings gear, 720p is crisp)

SD-WAN is illustrative of the adoption of virtualization, whether Network Virtualization or Network Function Virtualization (NFV, the separation of network functionality from specific network equipment). As shown in the video, SD-WAN features the high degree of automation characteristic of SDN in general. In the WAN, this will translate to some reduction in provisioning and maintenance costs, as well as an expansion of capabilities and offerings.

SD-WAN’s embrace of the low-cost, broadly available Internet is its fundamental point of divergence from MPLS. This was recognized in its conception and guided its design. Vis-à-vis MPLS, SD-WAN offers similar virtual private networking capabilities and a high degree of QoS management, although it will be challenged to meet the same QoS/SLA standards as MPLS, particularly for “voice grade” CoS/QoS-level services. Showing innovation, SD-WAN does implement some measures (e.g. error correction techniques, dynamic rerouting) to mitigate Internet transport impairments. Additionally, MPLS offers an inherent degree of security as it typically operates on private networks not connected to the Internet. Being Internet-centric, SD-WAN addresses security with IPSec (or similar) tunnels, and high levels of encryption with well-considered key management. Many of these features and others discussed in the video are summarized in the figure below.

Summary of SD-WAN in a Single Image

The adoption of cloud and cloud-based services (e.g. security) with their more dynamic connectivity needs are a better match for SD-WAN, but while co-existence seems imminent, it remains to be seen if SD-WAN will supplant MPLS’ position as the leading WAN solution in the large enterprise market.