1. What do devices on the same IPv4 subnet have in common?
- They all use the same default gateway.
- They all have a subnet mask of /8, /16, or /24.
- They all have the same last octet in their IPv4 addresses.
- They all have the same number in the first three octets of their IPv4 address.
Explanation: Devices on the same subnet will share the same network number, subnet mask, and default gateway. The default gateway is the IPv4 address of the Layer 3 device that allows the devices on the same subnet to communicate with other networks.
2. Refer to the exhibit. A network administrator has added a new subnet to the network and needs hosts on that subnet to receive IPv4 addresses from the DHCPv4 server.
What two commands will allow hosts on the new subnet to receive addresses from the DHCP4 server? (Choose two.)
- R1(config)# interface G0/0
- R1(config-if)# ip helper-address 10.2.0.250
- R2(config)# interface G0/0
- R2(config-if)# ip helper-address 10.2.0.250
- R1(config-if)# ip helper-address 10.1.0.254
- R1(config)# interface G0/1
Explanation: The ip helper-address command is used to configure a router to be a DHCPv4 relay. The command should be placed on the interface facing the DHCPv4 clients. When the command is applied on the router interface, the interface will receive DHCPv4 broadcast messages and forward them as unicast to the IP address of the DHCPv4 server.
3. Refer to the exhibit. How will R1 generate the interface ID portion of the IPv6 address on interface FastEthernet 0/0?
- by using stateful DHCP
- by using a manually set value of 64
- by using a randomly generated 64-bit number
- by using the interface MAC address with a 16-bit filler
Explanation: A router interface will generate an EUI-64 interface ID that is based on the interface MAC address. The EUI-64 process takes the 48-bit MAC address, splits it in half, adds the hex value FFFE in the middle, and then flips the seventh bit.
4. What is the function of ARP?
- resolves domain names to IP addresses
- provides automatic IP address assignments to hosts
- sends error and operational information messages to hosts
- maps IPv4 addresses to MAC addresses
Explanation: ARP, or Address Resolution Protocol, is used by hosts to resolve a destination MAC address from a given destination IP address.
5. Which command will create a static route on R2 in order to reach PC B?
- R2(config)# ip route 172.16.2.1 255.255.255.0 172.16.3.1
- R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.2.254
- R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.3.1
- R2(config)# ip route 172.16.3.0 255.255.255.0 172.16.2.254
Explanation: The correct syntax is:
router(config)# ip route*destination-network destination-mask{next-hop-ip-address | exit-interface*}
If the local exit interface instead of the next-hop IP address is used then the route will be displayed as a directly connected route instead of a static route in the routing table. Because the network to be reached is 172.16.2.0 and the next-hop IP address is 172.16.3.1, the command is R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.3.1
6. Which statement describes one purpose of the subnet mask setting for a host?
- It is used to describe the type of the subnet.
- It is used to identify the default gateway.
- It is used to determine to which network the host is connected.
- It is used to determine the maximum number of bits within one packet that can be placed on a particular network.
Explanation: An IPv4 address contains two portions. The network portion defines the network (or a subnet) where the host is located and the host portion identifies the host address on the network. The subnet mask is used to define the network portion of the IPv4 addressing through the logical ANDing of the IP address and the subnet mask.
7. Refer to the exhibit. Host A is unable to obtain an IP address from the DHCP server. Which procedure would solve this problem?
- Configure interface Fa0/0 of router RTA with the ip helper-address 10.1.2.1 command.
- Configure interface Fa0/0 of router RTA with the ip helper-address 10.1.2.10 command.
- Configure interface Fa0/1 of router RTA with the ip helper-address 10.1.2.10 command.
- Configure interface Fa0/0 of router RTA with the ip forward-protocol 67 command.
Explanation: Because host A and the DHCP server are on different IP networks, router RTA must be configured as a DHCP relay to forward DHCP messages by using the ip helper-address command. The command should be on the interface connecting the host and include the IP address of the DHCP server, 10.1.2.10.
8. What two methods can be used to generate an interface ID by an IPv6 host that is using SLAAC? (Choose two.)
- EUI-64
- random generation
- stateful DHCPv6
- DAD
- ARP
Explanation: A host that is using SLAAC has two means to configure an interface ID: EUI-64 and random generation by the host operating system.
9. Which routing protocol uses an administrative distance of 110?
- RIP
- OSPF
- EIGRP
- BGP
Explanation: The administrative distance indicates the reliability of a routing protocol. The administrative distance of OSPF is 110.
10. Which type of packet is sent by a DHCP server after receiving a DHCP Discover message?
- DHCP ACK
- DHCP Discover
- DHCP Offer
- DHCP Request
Explanation: When a DHCP server receives a DHCP Discover packet from a client, the server responds with a DHCP Offer packet to let the client know that an IP address is available and reserved for the client.
11. What are the two main components of Cisco Express Forwarding (CEF)? (Choose two.)
- adjacency tables
- MAC-address tables
- routing tables
- ARP tables
- forwarding information base (FIB)
Explanation: The forwarding information base (FIB) and adjacency tables are the main components of CEF. The FIB is similar to a routing table, but neither the routing table, nor the ARP table, nor the MAC-address table is part of CEF.
12. Which destination IP address is used when an IPv6 host sends a DHCPv6 SOLICIT message to locate a DHCPv6 server?
- FF02::1:2
- FF02::1
- FE80::1
- FF02::2
Explanation: DHCPv6 hosts will send a DHCP SOLICIT message to the all DHCP routers multicast address of FF02::1:2.
“Do I Know This Already?” Quiz Answers:
1. What occurs when a PC with the IP address 10.1.1.27/28 needs to communicate with a PC that has IP address 10.1.1.18? (Choose two.)
- a. It sends the frame to its default gateway.
- b. It sends the frame directly to the destination PC.
- c. It uses ARP to get the MAC address of the default gateway.
- d. It uses ARP to get the MAC address of the destination PC.
2. What occurs when a PC with the IP address 10.1.1.27/29 needs to communicate with a PC that has IP address 10.1.1.18? (Choose two.)
- a. It sends the frame to its default gateway.
- b. It sends the frame directly to the destination PC.
- c. It uses ARP to get the MAC address of the default gateway.
- d. It uses ARP to get the MAC address of the destination PC.
3. Which command enables you to verify the IP address configured on a router’s interface?
- a. ipconfig
- b. show ip interface
- c. arp -a
- d. show ip arp
4. What is the correct order of operations for the DHCP for IPv4 process?
- a. Offer, Request, Ack, Discover
- b. Discover, Request, Ack, Offer
- c. Request, Offer, Discover, Ack
- d. Discover, Offer, Request, Ack
5. Which command is needed on a router interface to forward DHCP Discover messages to a DHCP server on a different subnet?
- a. ip address dhcp
- b. ip helper-address
- c. ip dhcp-forwarder
- d. ip dhcp server
6. Which command enables a router interface to obtain an IP address from a DHCP server?
- a. ip dhcp client
- b. ip dhcp server
- c. ip address dhcp
- d. ip helper-address
7. What protocol is used with IPv6 to determine the MAC address of a device in the same local area network?
- a. Address Resolution Protocol
- b. Inverse Address Resolution Protocol
- c. Neighbor Discovery Protocol
- d. Neighbor Solicitation
8. Which of the following are true when using EUI-64? (Choose two.)
- a. The interface MAC address is used unmodified.
- b. The interface MAC address is used with FFFE added to the middle.
- c. The seventh bit from the left in the MAC address is flipped.
- d. The seventh bit from the right in the MAC address is flipped.
9. What command is used on a Cisco IOS router to enable SLAAC on an interface?
- a. ipv6 address autoconfig
- b. ipv6 address dhcp
- c. ipv6 address prefix eui-64
- d. ipv6 nd ra suppress
10. Which of the following are requirements for stateless address autoconfiguration to function? (Choose three.)
- a. The prefix must be /64.
- b. The router must be sending and not suppressing RA messages.
- c. The router must be enabled for IPv6 unicast routing.
- d. The router must be sending RS messages.
11. Which command is used to enable a router to inform clients that they need to get additional configuration information from a DHCPv6 server?
- a. ipv6 nd ra suppress
- b. ipv6 dhcp relay destination
- c. ipv6 address autoconfig
- d. ipv6 nd other-config-flag
12. What command enables you to configure a router interface as a DHCPv6 relay agent?
- a. ipv6 forwarder
- b. ipv6 helper-address
- c. ipv6 dhcp relay destination
- d. ipv6 dhcp client
13. Which two data structures reside at the router’s data plane?
- a. IP routing table
- b. ARP cache
- c. Forwarding Information Base
- d. Adjacency table
14. Which command enables you to verify routes in the FIB?
- a. show ip route
- b. show ip arp
- c. show ip cef
- d. show adjacency detail
15. Which of the following populate a routing protocol’s data structure, such as the EIGRP topology table? (Choose three.)
- a. Updates from a neighbor
- b. Redistributed routes
- c. Interfaces enabled for the routing process
- d. Static routes
16. Which of the following has the lowest default administrative distance?
- a. OSPF
- b. EIGRP (internal)
- c. RIP
- d. eBGP
17. What is the default administrative distance of an OSPF intra-area route?
- a. 90
- b. 110
- c. 115
- d. 120
18. How can you create a floating static route?
- a. Provide the static route with a metric higher than the preferred source of the route.
- b. Provide the static route with a metric lower than the preferred source of the route.
- c. Provide the static route with an AD higher than the preferred source of the route.
- d. Provide the static route with an AD lower than the preferred source of the route.
19. What occurs when you create an IPv4 static route with an Ethernet interface designated instead of a next-hop IP address?
- a. The router uses ARP to get the MAC address of the directly connected router’s IP address.
- b. The router forwards the packet with the destination MAC address FFFF:FFFF:FFFF.
- c. The router uses ARP to get the MAC address of the IP address in the source of the packet.
- d. The router uses ARP to get the MAC address of the IP address in the destination of the packet.