At its core, a WAN is a network of networks. The Internet itself is a giant WAN, and how you connect to it can be as diverse as through an Ethernet cable, coaxial cable, or a cellular radio signal.

Other SD-WAN services are providing pieces of the secure SD-WAN. Aryaka, for example, offers basic firewall capabilities, with its SD-WAN service, but fails to provide L4 to L7 controls, such as ...