4G Wireless Tunneling
In the graphic below, a mobile phone has a TCP connection with the streaming server using wireless 4G. Assume that both the mobile phone and the server use TCP port 11408 and any intermediary nodes that tunnel the datagrams use port 3773.
Question List
1. What is the source IP address of the datagram sent from the mobile phone to the base station?
2. What is the destination IP address of the datagram sent from the mobile phone to the base station?
3. What is the transport-layer port number in the datagram sent from the mobile phone to the base station?
4. What transport-layer protocol is indicated in the datagram sent from the mobile phone to the base station?
5. Is there an encapsulated datagram within the datagram sent from the mobile phone to the base station? Answer Yes or No
6. What is the source IP address of the datagram sent from the base station to the serving gateway?
7. What is the destination IP address of the datagram sent from the base station to the serving gateway?
8. What is the transport-layer port number in the datagram sent from the base station to the serving gateway?
9. What transport-layer protocol is indicated in the datagram sent from the base station to the serving gateway?
10. Is there an encapsulated datagram within the datagram sent from the base station to the serving gateway? Answer Yes or No
11. What is the source IP address of the encapsulated datagram?
12. What is the destination IP address of the encapsulated datagram?
13. What is the transport-layer port number in the encapsulated datagram?
14. What transport-layer protocol is indicated in the encapsulated datagram?
15. What is the source IP address of the datagram sent from the serving gateway to the PDN gateway?
16. What is the destination IP address of the datagram sent from the serving gateway to the PDN gateway?
17. What is the transport-layer port number in the datagram sent from the serving gateway to the PDN gateway?
18. What transport-layer protocol is indicated in the datagram sent from the serving gateway to the PDN gateway?
19. Is there an encapsulated datagram within the datagram sent from the serving gateway to the PDN gateway? Answer Yes or No
20. What is the source IP address of the encapsulated datagram?
21. What is the destination IP address of the encapsulated datagram?
22. What is the transport-layer port number in the encapsulated datagram?
23. What transport-layer protocol is indicated in the encapsulated datagram?
24. What is the source IP address of the datagram sent from the PDN gateway to the server?
25. What is the destination IP address of the datagram sent from the PDN gateway to the server?
26. What is the transport-layer port number in the datagram sent from the PDN gateway to the server?
27. What transport-layer protocol is indicated in the datagram sent from the PDN gateway to the server?
28. Is there an encapsulated datagram within the datagram sent from the PDN gateway to the server? Answer Yes or No
29. Is data encrypted between the mobile phone and the base station? Answer Yes or No
30. Does the server know about any of the wireless tunneling? Answer Yes or No
Solution
1. From the mobile phone to the base station, the source address is 10.0.0.135
2. From the mobile phone to the base station, the destination address is 25.250.53.162
3. From the mobile phone to the base station, the port used is 11408
4. From the mobile phone to the base station, the protocol used is TCP
5. Is there an encapsulated datagram? No
6. From the base station to the serving gateway, the source address is 83.84.48.38
7. From the base station to the serving gateway, the destination address is 83.84.171.20
8. From the base station to the serving gateway, the port used is 3773
9. From the base station to the serving gateway, the protocol used is UDP
10. Is there an encapsulated datagram? Yes
11. The source address of the encapsulated datagram is 10.0.0.135
12. The destination address of the encapsulated datagram is 25.250.53.162
13. The port used in the encapsulated datagram is 11408
14. The protocol used in the encapsulated datagram is TCP
15. From the serving gateway to the PDN gateway, the source address is 83.84.171.20
16. From the serving gateway to the PDN gateway, the destination address is 133.215.208.66
17. From the serving gateway to the PDN gateway, the port used is 3773
18. From the serving gateway to the PDN gateway, the protocol used is UDP
19. Is there an encapsulated datagram? Yes
20. The source address of the encapsulated datagram is 10.0.0.135
21. The destination address of the encapsulated datagram is 25.250.53.162
22. The port used by the encapsulated datagram is 11408
23. The protocol used by the encapsulated datagram is TCP
24. From the PDN gateway to the server, the source address is 133.215.208.66
25. From the PDN gateway to the server, the destination address is 25.250.53.162
26. From the PDN gateway to the server, the port used is 11408
27. From the PDN gateway to the server, the protocol used is TCP
28. Is there an encapsulated datagram? No
29. Yes, the base station and mobile phone encrypt data between them
30. No, the server is blissfully unaware of the wireless infrastructure or tunneling
That's incorrect
That's correct
The answer was: 10.0.0.135
The answer was: 25.250.53.162
The answer was: 11408
The answer was: TCP
The answer was: No
The answer was: 83.84.48.38
The answer was: 83.84.171.20
The answer was: 3773
The answer was: UDP
The answer was: Yes
The answer was: 10.0.0.135
The answer was: 25.250.53.162
The answer was: 11408
The answer was: TCP
The answer was: 83.84.171.20
The answer was: 133.215.208.66
The answer was: 3773
The answer was: UDP
The answer was: Yes
The answer was: 10.0.0.135
The answer was: 25.250.53.162
The answer was: 11408
The answer was: TCP
The answer was: 133.215.208.66
The answer was: 25.250.53.162
The answer was: 11408
The answer was: TCP
The answer was: No
The answer was: Yes
The answer was: No