What’s a WAN?
As local area networks grew and developed, it became increasingly necessary to be able to connect their resources together over long distances. We initially met these challenges via the phone company network—the Public Switched Telephone Network (PSTN)—and the first successful network able to establish voice communications over disparate locations was born.
Few of us remember back to a world without phone service, which made PSTN an obvious solution. It was already a fully operational, circuit-switching network, enabling every phone call to establish a unique circuit from one endpoint (phone) to another through a path of switches. So, instead of reinventing the wheel to design LANs, early network planners used packet switching as their communications-delivery method. As you can imagine, wiring these packet-switched networks to enable communication over vast locales wasn’t exactly something we could get done quickly, so even wide area networks...
