I am having trouble figuring how to derive the numbers to the solution to the question. I am following the steps, however my numbers do not come near that of the solution. Can someone give a concise step by step way to figuring out both problems.

Solution

Answer:

`T = 0 RTT`

Sender sends frames 0, 1 and 2 (theoretically) simultaneously.

`T = 0.5RTT`

Receiver receives frames 0,1 and 2. Receiver updates `LFR = 2`

, `LAF = 5`

. Receiver sends `ACK`

for each of the three frames.

`T = 1 RTT`

Sender receives ACK for frames 0, 1, and 2, and sends out frames 3,4, and 5. Sender updates `LAR = 2`

, and `LFS = 5`

.

`T = 1.5 RTT`

Receiver receives frames 3 and 5. Receiver updates `LFR = 3`

, `LAF = 6`

. It sends an `ACK`

for frame 3.

`T = 2 RTT`

Sender receives ACK for frame 3, and sends out frame 6. Sender updates `LAR = 3`

, and `LFS = 6`

.

`T = 2.7 RTT`

Sender times out on frame `4`

.

`T = 0 RTT`

Sender sends frames 0, 1 and 2 (theoretically) simultaneously.

`T = 0.5RTT`

Receiver receives frames 0,1 and 2. Receiver updates `LFR = 2`

, `LAF = 5`

. Receiver sends `ACK`

for each of the three frames.

`T = 1 RTT`

Sender receives ACK for frames 0, 1, and 2, and sends out frames 3,4, and 5. Sender updates `LAR = 2`

, and `LFS = 5`

.

`T = 1.5 RTT`

Receiver receives frames 3,4, and 5. Receiver updates `LFR = 5`

, `LAF = 8`

. It sends an ACK for each of the frames received.

`T = 2 RTT`

Sender receives ACK for frame 5, and sends out frames 6,7, 8. Sender updates `LAR = 5`

, and `LFS = 8`

.

`T = 2.5 RTT`

Receiver receives frames 6,7, and 8. Receiver updates `LFR = 8`

, `LAF = 11`

. It sends an ACK for each of the frames received.

`T = 2.7 RTT`

Sender is times out on frame `4`

.

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