A WAN is not only the physical line. It is also made up of networking hardware, software, and other technologies. An example of a networking technology is MPLS which helped make WANs faster and less expensive. MPLS uses short router adresses in a VPN, designed to get from one network site to another, thereby lessening the call on router databases. A SD-WAN (Software Defined WAN) is a culmination of technologies that replace expensive routers and make the network development and expansion much faster and cheaper.