Calculate the total time required to transfer a 1.5 MB file in the following cases, assuming an RTT of 80 ms, a packet size of 1 kB data, and an initial 2 × RTT of “handshaking” before data are sent.

(a) The bandwidth is 10 Mbps, and data packets can be sent continuously.

(b) The bandwidth is 10 Mbps, but after we finish sending each data packet, we must wait one RTT before sending the next.

(c) The link allows infinitely fast transmit but limits bandwidth such that only 20 packets can be sent per RTT.

(d) Zero transmit time as in (c), but during the first RTT, we can send one packet, during the second RTT we can send two packets, during the third we can send four = 23−1, etc.