MMIS 653 (Fall 2022)
Total points: 80
Due date: 9/11/22 11:59PM
Questions:
1, Suppose there are exactly two packet switches .
between a sending host and a receiving host. The transmission rate between the sending host and switch#1 is R1, 200Mbps. The transmissions rate between switch#1 and switch#2 and between switch#2 and the receiving host are R2, 400Mbps and R3,
500Mbps, respectively. Assuming that the switches use store–and–forward packet
switching, what is the total end–to–end delay to send a packet of length L, 1000 bytes?
2, (a) In general, how long does it take a packet of length L to be delivered from the
sending host to the receiving host over a link of distance d, propagating speed s,
and transmission rate R bps?
(b) How many milliseconds (ms) does it take for a packet of length 1,000 bytes to be
delivered from the sending host to the receiving host over a link of distance 2,000
km, propagation speed 2.5x108 m/s, and transmission rate 50Mbps ?
(c) How many milliseconds does it take for the first bit of the packet to arrive at the
receiving host ?
(d) How many milliseconds does it take for the whole packet to be put on the link?
3,Suppose Host A wants to send a large file to Host B. The path from Host A
to Host B has three links, of rate R1=100Mbps, R2=500Mbps, and R3=200Mbps.
(a) Assume no other traffic in the network, what is the throughput for the file transfer?
(b) Suppose the file is 500MB .Dividing the file size by
the throughput, roughly how long will it take to transfer the file to Host B?
