Virtual Circuit — Test 1

Correct Answer: D. D. Virtual circuit network is implemented in application layer
Explanation: Virtual circuit network is normally implemented in data link layer. It is a combination of circuit-switched network and datagram network which are implemented in the physical layer and network layer respectively.

Correct Answer: A. A. Global address
Explanation: Global address is a network address that is unique internationally and is used as a common address by all the users of the network. It is used to create a virtual circuit identifier.

Correct Answer: B. B. Virtual circuit identifier
Explanation: A virtual circuit identifier is a type of numeric identifying address that is used to distinguish between different virtual circuits in a circuit-switched network. It is used for data transfer and has a switch scope.

Correct Answer: C. C. Termination phase
Explanation: There are three phases in a virtual circuit network: setup, data transfer and teardown phase. There is no termination phase in it.

Correct Answer: A. A. Setup request and acknowledgement
Explanation: Setup request (sent by a source) and acknowledgement (sent by the destination) are the steps in the setup process. Both the ends’ switches make table entries during the setup process.

Correct Answer: B. B. Teardown request
Explanation: The source, after sending all the frames to destination sends teardown request to which, destination sends teardown response. The switches then delete the corresponding table entries.

Correct Answer: C. C. Same for each packet
Explanation: If a resource is allocated during setup phase, delay is same for each packet as there is only one-time delay during the setup phase and no delay during the data transfer phase.

Correct Answer: D. D. Different for each packet
Explanation: If a resource is to be allocated on demand during the data transfer phase, the delay for each packet would be different depending upon the resource requirement of the packets.

Correct Answer: A. A. 1 and 1
Explanation: There is one-time delay for both setup and teardown phase. The one-time delay in setup phase is for resource allocation and the one-time delay in teardown phase is for the de-allocation of the resources.

Correct Answer: D. D. 4
Explanation: The switch maintains a table for each Virtual Circuit Network. In the data transfer phase, it maintains 2 columns each for incoming data and outgoing data. The columns are in the following order: Source port, Source VCI, Destination port, Destination VCI.