A Refresher Switched networks always involve switches of some sort that are interconnected by circuits . At the simplest level, a switch serves to interconnect circuits through a switching matrix. The path through the switching matrix is a logical path that comprises one or more internal physical circuits.
All contemporary switches have certain things in common.
Like any other computer system, they consist of cabinets, shelves, printed circuit boards, port interfaces, power supplies and so on. Taken together, the common control element controls the operation of the system and its various components. The switching matrix comprises an intricately interconnected set of internal circuitry that connects incoming ports to outgoing ports. The port interfaces serve to establish physical connectivity between the switch and the external circuits, which may be either metallic or optical in nature. In the core, or backbone, the WAN core switches, also known as backbone switches or tandem switches, are positioned.