Consider sending a file of F bytes over a path of Q links. Each link transmits at R bps. The network is lightly loaded so that there are no queuing delays. Propagation delay on each link is Tp on average.
a. Suppose the network is a packet-switched virtual-circuit (VC) network. Denote the VC setup time by Ts seconds. Suppose the sending layers add a total of h bits of header to each packet. How long does it take to send the file from source to destination?
b. Suppose the network is a packet-switched datagram network, and a connectionless service is used. Now suppose each packet has 2h bits of header. How long does it take to send the packet?
c. Finally, suppose that the network is a circuit-switched network. Further suppose that the transmission rate of the circuit between source and destination is R bps. Assuming Ts setup time and h bits of header appended to the packet, how long does it take to send the packet?