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



Question List


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

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

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

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

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

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

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

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

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

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

11. Is the datagram being forwarded from a to b an IPv4 or IPv6 datagram?

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

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

14. Is this a to b datagram encapsulating another datagram? Yes or No.

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

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

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

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

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

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

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

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

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

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

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




Solution


1. The datagram is an IPv6 datagram.

2. The source IP address is 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

3. The destination IP address is A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

4. No, the datagram is NOT encapsulated.

5. The datagram is an IPv4 datagram.

6. The source IP address is 55.243.239.180

7. The destination IP address is 203.69.187.231

8. Yes, the datagram is encapsulated.

9. The source address of this encapsulated datagram is 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

10. The destination address of this encapsulated datagram is A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

11. The datagram is an IPv4 datagram.

12. The source IP address is 55.243.239.180

13. The destination IP address is 203.69.187.231

14. Yes, the datagram is encapsulated.

15. The source address of this encapsulated datagram is 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

16. The destination address of this encapsulated datagram is A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

17. The datagram is an IPv4 datagram.

18. The source IP address is 55.243.239.180

19. The destination IP address is 203.69.187.231

20. Yes, the datagram is encapsulated.

21. The source address of this encapsulated datagram is 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

22. The destination address of this encapsulated datagram is A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

23. The tunnel entrance is router C

24. The tunnel exit is router F

25. 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: IPv6

Question 1 of 25

The answer was: 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

Question 2 of 25

The answer was: A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

Question 3 of 25

The answer was: No

Question 4 of 25

The answer was: IPv4

Question 5 of 25

The answer was: 55.243.239.180

Question 6 of 25

The answer was: 203.69.187.231

Question 7 of 25

The answer was: Yes

Question 8 of 25

The answer was: 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

Question 9 of 25

The answer was: A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

Question 10 of 25

The answer was: IPv4

Question 11 of 25

The answer was: 55.243.239.180

Question 12 of 25

The answer was: 203.69.187.231

Question 13 of 25

The answer was: Yes

Question 14 of 25

The answer was: 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

Question 15 of 25

The answer was: A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

Question 16 of 25

The answer was: IPv4

Question 17 of 25

The answer was: 55.243.239.180

Question 18 of 25

The answer was: 203.69.187.231

Question 19 of 25

The answer was: Yes

Question 20 of 25

The answer was: 7441:3A44:D3EC:284F:47A9:DA63:1EBC:284B

Question 21 of 25

The answer was: A856:FAE7:B281:E625:65D2:D6C7:5C69:1AC5

Question 22 of 25

The answer was: C

Question 23 of 25

The answer was: F

Question 24 of 25

The answer was: IPv4

Question 25 of 25

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