Interactive end-of-chapter exercises


Supplement to Computer Networking: A Top Down Approach 8th Edition


"Tell me and I forget. Show me and I remember. Involve me and I understand." Chinese proverb

Textbook Cover

UDP Multiplexing and Demultiplexing

In the scenario below, the left and right clients communicate with a server using UDP sockets. The same socket at the server is used to communicate with both clients. The Python code used to create the sockets is shown in the figure. Consider the four transport-layer packets – A, B, C and D – shown in the figure below.




Question List


1. What is the source port # for packet C?

2. What is the destination port # for packet C?

3. What is the source port # for packet B?

4. What is the destination port # for packet B?

5. What is the source port # for packet D?

6. What is the destination port # for packet D?

7. What is the source port # for packet A?

8. What is the destination port # for packet A?




Solution


1. The source port for packet C is port 7231.

2. The destination port for packet C is port 7434.

3. The source port for packet B is port 7434.

4. The destination port for packet B is port 5571.

5. The source port for packet D is port 7434.

6. The destination port for packet D is port 7231.

7. The source port for packet A is port 5571.

8. The destination port for packet A is port 7434.



That's incorrect

That's correct

The answer was: 7231

Question 1 of 8

The answer was: 7434

Question 2 of 8

The answer was: 7434

Question 3 of 8

The answer was: 5571

Question 4 of 8

The answer was: 7434

Question 5 of 8

The answer was: 7231

Question 6 of 8

The answer was: 5571

Question 7 of 8

The answer was: 7434

Question 8 of 8

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