SVC also stands for supervisor call.
In a network, a switched virtual circuit (SVC) is a temporary virtual circuit that is established and maintained only for the duration of a data transfer session. A permanent virtual circuit (PVC) is a continuously dedicated virtual circuit. A virtual circuit is one that appears to be a discrete, physical circuit available only to the user but that is actually a shared pool of circuit resources used to support multiple users as they require the connections. Switched virtual circuits are part of an X.25 network. Conceptually, they can also be implemented as part of a frame relay network.