eworks, Spring 2019
(6). Which of the following is not a field in a UDP segment header?
A. Source Port
B. Destination Port
C. Checksum
D. Sequence Number
7. When a computer joins a network, it usually uses
A. DNS
B. DHCP
C. ARP
D. ICMP
8. Which of the following best characterizes the medium access control mechanism used in Ethernet?
A. FDMA
B. CSMA/CA
C. CSMA/CD
D. TDMA
10. What do we call a packet at the data link layer?
A. Message
B. Segment
C. Datagram
11. Which of the following ICMP messages is used in the ping program?
A. Frame Destination port unreachable
B. TTL expired
C. Echo request
12. Which of the following ICMP messages is used in the traceroute program on Unix-like systems?
A. Destination port unreachable
B. Echo request
C. Echo reply
13. Which protocol/method do we use to get the IP address of a given hostname?
A. DHCP
B. DNS
C. ARP
D. Self-learning
14. Which protocol/method do we use to get the MAC address of an IP address in a local area network?
A. DHCP
B. DNS
C. ARP
D. Self-learning
15. Consider the following diagram on Network Address Translation (NAT). If host 192.168.0.2 sends a datagram out with source port number 3345, what will be the source port number after the datagram leaves the public interface of the NAT router?
A. 3007
B. 3008
C. 3009
D. 3345
NAT translation table:
WAN side addr 208.38.69.1,3007
192.168.0.1,3345
208.38.69.1,3008
192.168.0.2,3345
208.38.69.1,3009
192.168.0.3,3345
192.168.0.1
192.168.0.4
192.168.0.2
208.38.69.
192.168.0.3