1. What destination MAC address would be included in a frame sent from a source device to a destination device on the same local network?
- A. A broadcast MAC address of FF-FF-FF-FF-FF-FF.
- B. The MAC address of the destination device.
- C. The MAC address of the local router interface.
2. What destination MAC address would be included in a frame sent from a source device to a destination device on a remote local network?
- A. A broadcast MAC address of FF-FF-FF-FF-FF-FF.
- B. The MAC address of the destination device.
- C. The MAC address of the local router interface.
3. What two protocols are used to determine the MAC address of a known destination device IP address (IPv4 and IPv6)?
- A. DHCP
- B. ARP
- C. DNS
- D. ND
4. What two functions are provided by ARP? (Choose two.)
- A. Maintains a table of IPv4 address to domain names
- B. Maintains a table of IPv4 to MAC address mappings
- C. Maintains a table of IPv6 to MAC address mappings
- D. Resolves IPv4 addresses to domain names
- E. Resolves IPv4 addresses to MAC addresses
- D. Resolves IPv6 addresses to MAC addresses
6. Which statement is true about ARP?
- A. An ARP cache cannot be manually deleted.
- B. ARP entries are cached permanently.
- C. ARP entries are cached temporarily.
7. Which command could be used on a Cisco router to view its ARP table?
- A. Arp –a
- B. Arp -d
- C. Show arp table
- D. Show ip arp
8. What is an attack using ARP?
- A. ARP broadcasts
- B. ARP hopping attacks
- C. ARP poisoning
- D. ARP starvation
9. Which two ICMPv6 messages are used in SLAAC?
- A. Neighbor Advertisement
- B. Neighbor Solicitation
- C. Router Advertisement
- D. Router Solicitation
10. Which two ICMPv6 messages are used in to determine the MAC address of a known IPv6 address?
- A. Neighbor Advertisement
- B. Neighbor Solicitation
- C. Router Advertisement
- D. Router Solicitation
11. To what type of address are ICMPv6 neighbor solicitation messages sent?
- A. Unicast
- B. Multicast
- C. Broadcast
12. Which router component holds the routing table, ARP cache, and running configuration file?
- A. ROM
- B. RAM
- C. NVRAM
- D. Flash
The routing table, ARP cache, and running configuration file are stored in volatile RAM.
13. What type of information is contained in an ARP table?
- A. Routes to reach destination networks
- B. IPv4 address to MAC address mappings
- C. Switch ports associated with destination MAC addresses
- D. Domain name to IPv4 address mappings
ARP tables are used to store mappings of IPv4 addresses to MAC addresses. When a network device needs to forward a packet, the device knows only the IPv4 address. To deliver the packet on an Ethernet network, a MAC address is needed. ARP resolves the MAC address and stores it in an ARP table.
14. A PC is configured to obtain an IPv4 address automatically from network 192.168.1.0/24. The network administrator issues the arp –a command and notices an entry of 192.168.1.255 ff-ff-ff- ff-ff-ff. Which statement describes this entry?
- A. This is a dynamic map entry.
- B. This entry refers to the PC itself.
- C. This is a static map entry.
- D. This entry maps to the default gateway.
The IPv4 address of 192.168.1.255 on the 192.168.1.0/24 network is the broadcast address, which is statically mapped to ff-ff-ff-ff-ff-ff in the ARP table.
15. A cybersecurity analyst believes an attacker is spoofing the MAC address of the default gateway to perform a man-in-the-middle attack. Which command should the analyst use to view the MAC address a host is using to reach the default gateway?
- A. ipconfig /all
- B. netstat -r
- C. arp -a
- D. route print
ARP is a protocol used with IPv4 to map a MAC address to an associated specific IP address. The command arp -a will display the MAC address table on a Windows PC.
16. What will a Layer 2 switch do when the destination MAC address of a received frame is not in the MAC table?
- A. It notifies the sending host that the frame cannot be delivered.
- B. It broadcasts the frame out of all ports on the switch.
- C. It initiates an ARP request.
- D. It forwards the frame out of all ports except for the port at which the frame was received.
A Layer 2 switch determines how to handle incoming frames by using its MAC address table. When an incoming frame contains a destination MAC address that is not in the table, the switch forwards the frame out all ports, except for the port on which it was received.
17. Which two ICMPv6 messages are used during the Ethernet MAC address resolution process? (Choose two.)
- A. Neighbor solicitation
- B. Router solicitation
- C. Router advertisement
- D. Neighbor advertisement
IPv6 uses neighbor solicitation (NS) and neighbor advertisement (NA) ICMPv6 messages for MAC address resolution.
18. How does the ARP process use an IPv4 address?
- A. To determine the MAC address of the remote destination host
- B. To determine the amount of time a packet takes when traveling from source to destination
- C. To determine the MAC address of a device on the same network
- D. To determine the network number based on the number of bits in the IPv4 address
The ARP process is used to complete the necessary mapping of IPv4 and MAC addresses that are stored in the ARP table that is maintained by each node on a LAN. When the destination device is not on the same network as the source device, the MAC address of the Layer 3 device on the the source network is discovered and added to the ARP table of the source node.
19. What is one function of the ARP protocol?
- A. Mapping a domain name to its IP address
- B. Resolving an IPv4 address to a MAC address
- C. Obtaining an IPv4 address automatically
- D. Maintaining a table of domain names with their resolved IP addresses
The two main functions of the ARP protocol are to resolve an IPv4 address to a
MAC address and to maintain an ARP table, which lists the resolved pairs of IPv4 address and MAC address. A device automatically obtains an IP address through DHCP. The functions of DNS include resolving (or mapping) a domain name with its IP address and maintaining a table for the domain name/IP pairs.
20. Which action is taken by a Layer 2 switch when it receives a Layer 2 broadcast frame?
- A. It sends the frame to all ports except the port on which it received the frame.
- B. It drops the frame.
- C. It sends the frame to all ports.
- D. It sends the frame to all ports that are registered to forward broadcasts.
When a Layer 2 switch receives a frame with a broadcast destination address, it floods the frame to all ports except the port on which it received the frame.
21. What addresses are mapped by ARP?
- A. IPv4 address to a destination MAC address
- B. Destination MAC address to the source IPv4 address
- C. Destination IPv4 address to the source MAC address
- D. Destination IPv4 address to the destination host name
ARP, or the Address Resolution Protocol, works by mapping the IPv4 address to a destination MAC address. The host knows the destination IPv4 address and uses ARP to resolve the corresponding destination MAC address.
22. When an IPv4 packet is sent to a host on a remote network, what information is provided by ARP?
- A. The IPv4 address of the destination host
- B. The IPv4 address of the default gateway
- C. The MAC address of the switch port that connects to the sending host
- D. The MAC address of the router interface closest to the sending host
When a host sends an IPv4 packet to a destination on a different network, the Ethernet frame cannot be sent directly to the destination host because the host is not directly reachable in the same network. The Ethernet frame must be sent to another device known as the router or default gateway in order to forward the IPv4 packet. ARP is used to discover the MAC address of the router (or default gateway) and use it as the destination MAC address in the frame header.
23. The ARP table in a switch maps which two types of address together?
- A. Layer 2 address to a Layer 4 address
- B. Layer 3 address to a Layer 2 address
- C. Layer 4 address to a Layer 2 address
- D. Layer 3 address to a Layer 4 address
The switch ARP table keeps a mapping of Layer 2 MAC addresses to Layer 3 IP addresses. These mappings can be learned by the switch dynamically through ARP or statically through manual configuration.
24. What is the purpose of ARP in an IPv4 network?
- A. To build the MAC address table in a switch from the information that is gathered
- B. To forward data onward based on the destination IP address
- C. To forward data onward based on the destination MAC address.
- D. To obtain a specific MAC address when an IP address is known
ARP performs two functions: 1. To obtain a specific MAC address when an IP address is known, by broadcasting an ARP request message to all devices on a particular Ethernet network 2. To use the gathered information to create a viewable table of IP address to MAC address mappings
25. Which destination address is used in an ARP request frame?
- A. 0.0.0.0
- B. 127.0.0.1
- C. 01-00-5E-00-AA-23
- D. FFFF.FFFF.FFFF
- E. 255.255.255.255
The purpose of an ARP request is to find the MAC address of the destination host on an Ethernet LAN. The ARP process sends a Layer 2 broadcast to all devices on the Ethernet LAN. The frame contains the IP address of the destination and the broadcast MAC address, FFFF.FFFF.FFFF.