A CAN is a large private local area network in a common entity such as a college, hospital, corporate campus, or military base that has two or more interconnected LANs.

The CAN has a main campus where the central elements of a network reside, such as the data center and telephony, and provides connectivity, data, applications, and services to clients. Away from the main campus, there are remote locations.

Because the CAN, at times, is spread across a larger geographic area such as a city, remote locations communicate over a WAN using an internet connection. Let's now discover the qualities of a WAN.