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



Question List


1. Is the datagram being forwarded from B to c an IPv4 or IPv6 datagram?

2. What is the source address of this B to c datagram?

3. What is the destination address of this B to c datagram?

4. Is this B to c 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 c to a an IPv4 or IPv6 datagram?

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

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

10. Is this c to a 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 a to b an IPv4 or IPv6 datagram?

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

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

16. Is this a to b 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 b to F an IPv4 or IPv6 datagram?

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

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

22. Is this b to F 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. What router is the 'tunnel entrance'? Give the router's letter

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

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




Solution


1. The datagram is an IPv4 datagram.

2. The source IP address is 219.52.6.18

3. The destination IP address is 250.90.127.107

4. Yes, the datagram is encapsulated.

5. The source address of this encapsulated datagram is 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

6. The destination address of this encapsulated datagram is DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

7. The datagram is an IPv4 datagram.

8. The source IP address is 219.52.6.18

9. The destination IP address is 250.90.127.107

10. Yes, the datagram is encapsulated.

11. The source address of this encapsulated datagram is 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

12. The destination address of this encapsulated datagram is DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

13. The datagram is an IPv4 datagram.

14. The source IP address is 219.52.6.18

15. The destination IP address is 250.90.127.107

16. Yes, the datagram is encapsulated.

17. The source address of this encapsulated datagram is 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

18. The destination address of this encapsulated datagram is DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

19. The datagram is an IPv4 datagram.

20. The source IP address is 219.52.6.18

21. The destination IP address is 250.90.127.107

22. Yes, the datagram is encapsulated.

23. The source address of this encapsulated datagram is 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

24. The destination address of this encapsulated datagram is DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

25. The tunnel entrance is router B

26. The tunnel exit is router F

27. 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 27

The answer was: 219.52.6.18

Question 2 of 27

The answer was: 250.90.127.107

Question 3 of 27

The answer was: Yes

Question 4 of 27

The answer was: 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

Question 5 of 27

The answer was: DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

Question 6 of 27

The answer was: IPv4

Question 7 of 27

The answer was: 219.52.6.18

Question 8 of 27

The answer was: 250.90.127.107

Question 9 of 27

The answer was: Yes

Question 10 of 27

The answer was: 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

Question 11 of 27

The answer was: DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

Question 12 of 27

The answer was: IPv4

Question 13 of 27

The answer was: 219.52.6.18

Question 14 of 27

The answer was: 250.90.127.107

Question 15 of 27

The answer was: Yes

Question 16 of 27

The answer was: 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

Question 17 of 27

The answer was: DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

Question 18 of 27

The answer was: IPv4

Question 19 of 27

The answer was: 219.52.6.18

Question 20 of 27

The answer was: 250.90.127.107

Question 21 of 27

The answer was: Yes

Question 22 of 27

The answer was: 7F99:EDCE:CA13:52C7:9EC2:419B:818C:82C9

Question 23 of 27

The answer was: DFC5:62C1:374B:FC83:6FB4:EA67:6FA1:E672

Question 24 of 27

The answer was: B

Question 25 of 27

The answer was: F

Question 26 of 27

The answer was: IPv4

Question 27 of 27

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