Switched Virtual (data) Circuit - a connection-oriented packet service which establishes a virtual circuit when required, like a telephone call, as distinguished from a PVC (permanent virtual circuit) which is set when the link layer is initiated.
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Switched virtual circuit. Virtual circuit that is dynamically established on demand and is torn down when transmission is complete. SVCs are used in situations where data transmission is sporadic. Called a switched virtual connection in ATM terminology. Found on https://www.encyclo.co.uk/local/22803