A 10 Mbps point-to-point link being set up between the Earth and a new lunar colony. The distance from the moon to the Earth is approximately 242,000 miles, and data travels over the link at the speed of light—186,000 miles per second. The RTT for the link is 2.6 sec. The delay X bandwidth = 26 Mb=3.2 MB.

Suppose each image is transferred as a sequence of packets using the sliding window algorithm. Assuming each packet carries 4 KB of data
a. How many packets are outstanding in the link?

b. How many bits would be required for the packet-based sequence number for an optimal sliding widow protocol implementation?

c. How many bits would be required for a byte-offset sequence number like TCP’s?

d. Suppose the link ran at 10 Gbps, would TCP work? Would it fill the pipe? What if the file were 4 GB?

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