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A Go-Back-5 ARQ scheme is employed on a 200 meters cable between two nodes A and B to send frames of size 10,000 bits with bit rate 1 Mbps and bit error probability of 10$^{-5}$. Headers and acknowledgements are 20 bytes each. The Speed of propagation of signals on the cable is 200,000 km/s, and the processing delay is 11ms. Assume large m (sequencing its) for parts 1,2, and 3

1. On the above figure, label (write number of) the ACKs for the frames depicted by solid arrows. On the same figure, label the frame numbers depicted in dashed lines. On the same figure, plot and label ACKs (IF NEEDED) that node B would send as response to the frames depicted by dashed arrows.
2. What is the minimum number of bits that can be used for sequence numbers in this Go-Back-5 ARQ scheme to avoid confusion at node B?
3. What is the efficiency of this Go-Back-5 system ?
4. What is the minimum value of timeout time for this Go-Back-5 to avoid early timeouts ?
5. What is the minimum window size that could be employed for the above system to avoid early window exhaustion ?
6. Given the above parameter (except for the cable length), what is the maximum distance between the two nodes for which S&W will be as efficient as a GBN.

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