GATE Overflow Test Series | Mock GATE | Test 1 | Question: 19

Question

Which of the following is/are NOT correct? (Mark all the appropriate choices)

• A. In circuit switching, the resources need to be reserved during the setup phase
• B. In a packet-switched network, there is no resource reservation; resources are allocated on demand
• C. In packet-switching, all packets belonging to the same source and destination travel the same path
• D. In virtual-circuit switching, all packets belonging to the same source and destination travel the same path

Answer 1

In-circuit switching, the resources need to be reserved during the setup phase; the resources remain dedicated for the entire duration of data transfer until the teardown phase.

 In a packet-switched network, there is no resource reservation; resources are allocated on demand.

In packet-switching, all packets (or datagrams) belong to the same message but may travel different paths to reach their destination.

In virtual-circuit switching, all packets belonging to the same source and destination travel the same path; but the packets may arrive at the destination with different delays if resource allocation is on demand.

So, the correct answer is $(C).$

References: 

• http://faculty.wiu.edu/Y-Kim2/NET321F11ch8.pdf
• http://courseware.cutm.ac.in/wp-content/uploads/2020/06/CN-M2-3.pdf

Comments

Lakshman Patel RJIT 

gatecse

 

 

in packet switching there is virtual circuit and datagram subnet 

In virtual circuit resources are reserved since its connection oritened then why  B is always true. It can be false for VC . Please correct

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I also agree with @rupesh17 
@gatecse  @Lakshman Patel RJIT can you please explain why option b is not in answer?

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so in book forouzen it is mentioned

for Circuit switching:

Before starting communication, the stations must make a reservation for the resources to be used during the communication.

For vitrual circuit:

Resources can be allocated during the setup phase, as in a circuit-switched network, or on demand, as in a datagram network

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Can anyone explain how Option B is correct ? In Virtual-Circuit Packet switching we need to reserve resources right https://www.cs.princeton.edu/courses/archive/spring07/cos461/slides/22Circuits.ppt