1. Describe the UDP segment fields with the segment structure diagram. (10 Points)
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3. Compute the check sum for each of the following data payloads. (6 Points)

   0x1215

   0xFF09

   0xFF34

   0x1232

   0xAAEF

   0xAEFF

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5. Differentiate (at least two differences) between Go-Back-N (GBN) and Selective Repeat (SR) protocols. (4 Points)
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7. Describe the TCP segment fields with the segment structure diagram. (20 Points)
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10. Five values of SampleRTT are 10 ms, 5 ms, 15 ms, 25 ms, and 30 ms. Compute the EstimatedRTT, DevRTT, and Timeoutinterval after each of these SampleRTT values is obtained. Assume α = 0.125 and β = 0.25. Initial value of EstimatedRTT was 15 ms and initial value of DevRTT was 10 ms just before the first of these five samples was obtained. (15 Points)
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12. What is TCP fast retransmit? Use an example and explain the working of TCP fast retransmit. (5 Points)
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14. Describe how TCP flow control is done? (5 Points)
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16. What are the steps involved in opening and closing a TCP connection? Clearly state what information is exchanged between the client and the server during the opening and closing a TCP connection. (11 Points)
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18. Briefly explain TCP’s additive increase multiplicative decrease (AIMD) approach to congestion. (5 Points)
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20. Differentiate (at least two differences) between TCP Reno and TCP Tahoe. (4 Points)