SD-WAN Simply Explained
Software defined wide area networks (SD-WAN) is a new approach to multisite network connectivity that lowers operational costs and improves resource usage. Currently all the rage in IT, large corporations are buying up established players to integrate as part of their core offerings at an alarming rate. Often buzz words and IT concepts aren’t well explained, but instead assumed understood. Therefore, I’d like to step back in order to explain and explore SD-WAN.
Before we get bogged down with terms like QoS, MPLS and packet-based routing, let’s first review some general networking concepts and terms to build off of :
A local area network (LAN) is a private collection of devices in a small geographic location (i.e. your office building or home) connected together in a network in order to share resources.
A wide area network (WAN) works much the same way, but for devices geographically diverse. In order to ensure private and consistent communication between WAN locations, a leased, telecommunication circuit has been traditionally required – often in the form of an MPLS. Deploying a traditional WAN is not only complex, but typically quite expensive, especially compared to the ever-increasing standards of Internet speeds we expect. It is normal to see corporate MPLS speeds well below that which we get at home, and you can be sure they are exponentially expensive.
Enter the concept of a SD-WAN where a purpose built device uses software to define routes of privatized (encrypted) corporate data across the Internet using “standard”, less expensive, connections to ensure a high quality of service (QoS). These connections can be aggregated from separate providers, at different speeds, even using different mediums (cable, fiber, cellular 3G/4G, etc). This allows your data not only multiple, dynamic routes to reach you (ensuring network redundancy) but also aggregated speeds to allow for faster data transfer.
SD-WAN promises to modernize the concept of a traditional WAN in order to meet the needs and expectations of today’s businesses.