1. What does the data link layer add to a Layer 3 packet to create a frame? (Choose two.)
- flags
- sequence number
- header
- trailer
Explanation: The data link layer adds a header which contains the source and destination Layer 2 address and a trailer that contains a frame check sequence (FCS).
2. What is the function of the last field in a data link layer frame?
- To determine whether the frame experienced transmission errors
- To identify special flow control services such as quality of service (QoS)
- To identify the beginning and end limits of the frame
- To identify the Layer 3 protocol in the data field
Explanation: The last field in the data link frame is the frame check sequence (FCS) which is used to determine if the frame has experienced transmission errors.
3. Which lists the Layer 2 and Layer 3 address fields in the correct order?
- destination NIC address, source NIC address, source IP address, destination IP address
- source NIC address, destination NIC address, source IP address, destination IP address
- destination NIC address, source NIC address, destination IP address, source IP address
- source NIC address, destination NIC address, destination IP address, source IP address
Explanation: The correct order of Layer 2 and Layer 3 address fields is: destination NIC address, source NIC address, source IP address, destination IP address
4. Which of the following are data link layer protocols? (Choose three)
- 802.11
- Ethernet
- IP
- PPP
- UDP
Explanation: 802.11, Ethernet, and PPP are Layer 2 protocols. IP is Layer 3 and UDP is Layer 4.