Interactive end-of-chapter exercises


IPv6 Tunneling and Encapsulation

Consider the network shown below which contains four IPv6 subnets, connected by a mix of IPv6-only routers(shaded blue), IPv4-only routers (shaded red) and dual-capable IPv6/IPv4 routers (shaded blue with red interfaces to IPv4 routers). You might want to review Section 4.3.4 in the textbook before doing this problem.


Suppose that a host of subnet F wants to send an IPv6 datagram to a host on subnet A. Assume that the forwarding between these two hosts goes along the path: F --> b --> c --> a --> C --> A



Question List


1. Is the datagram being forwarded from F to b an IPv4 or IPv6 datagram?

2. What is the source address of this F to b datagram?

3. What is the destination address of this F to b datagram?

4. Is this F to b datagram encapsulating another datagram? Yes or No.

5. What is the source address of this encapsulated datagram?

6. What is the destination address of this encapsulated datagram?

7. Is the datagram being forwarded from b to c an IPv4 or IPv6 datagram?

8. What is the source address of this b to c datagram?

9. What is the destination address of this b to c datagram?

10. Is this b to c datagram encapsulating another datagram? Yes or No.

11. What is the source address of this encapsulated datagram?

12. What is the destination address of this encapsulated datagram?

13. Is the datagram being forwarded from c to a an IPv4 or IPv6 datagram?

14. What is the source address of this c to a datagram?

15. What is the destination address of this c to a datagram?

16. Is this c to a datagram encapsulating another datagram? Yes or No.

17. What is the source address of this encapsulated datagram?

18. What is the destination address of this encapsulated datagram?

19. Is the datagram being forwarded from a to C an IPv4 or IPv6 datagram?

20. What is the source address of this a to C datagram?

21. What is the destination address of this a to C datagram?

22. Is this a to C datagram encapsulating another datagram? Yes or No.

23. What is the source address of this encapsulated datagram?

24. What is the destination address of this encapsulated datagram?

25. Is the datagram being forwarded from C to A an IPv4 or IPv6 datagram?

26. What is the source address of this C to A datagram?

27. What is the destination address of this C to A datagram?

28. Is this C to A datagram encapsulating another datagram? Yes or No.

29. What router is the 'tunnel entrance'? Give the router's letter

30. What router is the 'tunnel exit'? Give the router's letter

31. Which protocol encapsulates the other, IPv4 or IPv6?




Solution


1. The datagram is an IPv4 datagram.

2. The source IP address is 32.94.155.189

3. The destination IP address is 34.81.101.245

4. Yes, the datagram is encapsulated.

5. The source address of this encapsulated datagram is 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

6. The destination address of this encapsulated datagram is 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

7. The datagram is an IPv4 datagram.

8. The source IP address is 32.94.155.189

9. The destination IP address is 34.81.101.245

10. Yes, the datagram is encapsulated.

11. The source address of this encapsulated datagram is 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

12. The destination address of this encapsulated datagram is 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

13. The datagram is an IPv4 datagram.

14. The source IP address is 32.94.155.189

15. The destination IP address is 34.81.101.245

16. Yes, the datagram is encapsulated.

17. The source address of this encapsulated datagram is 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

18. The destination address of this encapsulated datagram is 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

19. The datagram is an IPv4 datagram.

20. The source IP address is 32.94.155.189

21. The destination IP address is 34.81.101.245

22. Yes, the datagram is encapsulated.

23. The source address of this encapsulated datagram is 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

24. The destination address of this encapsulated datagram is 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

25. The datagram is an IPv6 datagram.

26. The source IP address is 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

27. The destination IP address is 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

28. No, the datagram is NOT encapsulated.

29. The tunnel entrance is router F

30. The tunnel exit is router C

31. IPv4, in order to maintain compatibility with existing IPv4 infrastructure, IPv6 datagrams are put in the payload of an IPv4 datagram. These IPv4 datagrams are passed on until it reaches a router which supports IPv6, where the IPv6 datagram is decapsulated and passed on.



That's incorrect

That's correct

The answer was: IPv4

Question 1 of 31

The answer was: 32.94.155.189

Question 2 of 31

The answer was: 34.81.101.245

Question 3 of 31

The answer was: Yes

Question 4 of 31

The answer was: 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

Question 5 of 31

The answer was: 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

Question 6 of 31

The answer was: IPv4

Question 7 of 31

The answer was: 32.94.155.189

Question 8 of 31

The answer was: 34.81.101.245

Question 9 of 31

The answer was: Yes

Question 10 of 31

The answer was: 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

Question 11 of 31

The answer was: 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

Question 12 of 31

The answer was: IPv4

Question 13 of 31

The answer was: 32.94.155.189

Question 14 of 31

The answer was: 34.81.101.245

Question 15 of 31

The answer was: Yes

Question 16 of 31

The answer was: 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

Question 17 of 31

The answer was: 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

Question 18 of 31

The answer was: IPv4

Question 19 of 31

The answer was: 32.94.155.189

Question 20 of 31

The answer was: 34.81.101.245

Question 21 of 31

The answer was: Yes

Question 22 of 31

The answer was: 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

Question 23 of 31

The answer was: 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

Question 24 of 31

The answer was: IPv6

Question 25 of 31

The answer was: 2BF7:32C1:8D39:5AE3:3226:BE43:33CF:626A

Question 26 of 31

The answer was: 3B71:7AF9:AB81:4D8F:34F5:D2EE:BAE7:734B

Question 27 of 31

The answer was: No

Question 28 of 31

The answer was: F

Question 29 of 31

The answer was: C

Question 30 of 31

The answer was: IPv4

Question 31 of 31

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