Software Defined WAN (SD-WAN) Feature Overview and Configuration Guide

Software defined WAN (SD-WAN) simplifies the management and operation of a wide area network (WAN) by decoupling the networking hardware from its control mechanism. This lets you create fully managed multi-site networks, integrating links and optimising application flows to the Internet and across the enterprise VPN infrastructure.

Phase 1 of the Allied Telesis SD-WAN solution is able to determine the quality of virtual tunnel interface (VTI) links connecting a spoke site to a central site. It can then dynamically redirect performance sensitive traffic (for example voice or video) onto links which meet its performance requirements. Certain types of traffic have very specific performance requirements to work correctly. High latency or jitter can severely degrade user experience for applications or devices which stream voice or video traffic. Usually, cheap Internet links are able to meet the performance requirements for these applications. However, this is not guaranteed and performance can fluctuate dramatically. Because of this, businesses have been required to purchase expensive virtual private network (VPN) solutions such as frame-relay and multi-protocol label switching (MPLS), with a committed information rate high enough to meet their needs.

This SD-WAN solution minimizes or outright replaces the need for these expensive VPN links, replacing them with cheap Internet links. It can do this by using probes to determine the jitter, latency, and packet-loss of tunnels between a spoke and central site. When performance on a given tunnel no longer meets the performance requirements for a given application, it can be redirected onto a link which does.