(1) A temporary communications path created between devices in a switched communications system. For example, a message from New York to Los Angeles may actually be routed through Atlanta and St. Louis. Within a smaller geography, such as a building or campus, the virtual circuit traverses some number of switches, hubs and other network devices.
(2) A logical circuit within a physical network. The actual lines may be shared by other users at the same time, but the virtual circuit appears exclusive to the users who are communicating with each other. The terms "permanent virtual circuit" and "virtual private network" (VPN) also describe this kind of logical circuit. See
packet switching,
VPN,
PVC and
SVC.