6.8.4 Module Quiz – NAT for IPv4 Answers
1. Which two statements accurately describe an advantage or a disadvantage when deploying NAT for IPv4 in a network? (Choose two.)
- NAT adds authentication capability to IPv4.
- NAT introduces problems for some applications that require end-to-end connectivity.
- NAT provides a solution to slow down the IPv4 address depletion.
- NAT causes routing tables to include more information.
- NAT improves packet handling.
- NAT will impact negatively on switch performance.
2. A network administrator wants to examine the active NAT translations on a border router. Which command would perform the task?
- Router# clear ip nat translations
- Router# show ip nat translations
- Router# debug ip nat translations
- Router# show ip nat statistics
3. What are two tasks to perform when configuring static NAT? (Choose two.)
- Configure a NAT pool.
- Identify the participating interfaces as inside or outside interfaces.
- Define the outside global address.
- Define the inside global address on the server
- Create a mapping between the inside local and inside global addresses.
4. What is a disadvantage of NAT?
- The router does not need to alter the checksum of the IPv4 packets.
- There is no end-to-end addressing.
- The costs of readdressing hosts can be significant for a publicly addressed network.
- The internal hosts have to use a single public IPv4 address for external communication.
5. What is one advantage of using NAT at the edge of the network?
- Changing ISPs is simpler because the devices on the inside network do not have to be configured with new addresses when the outside address changes.
- Dynamic NAT allows devices from outside the local network to easily initiate TCP connections to inside hosts.
- NAT enables end-to-end IPv4 traceability, making troubleshooting easier.
- Performance is significantly increased because the router does not have to perform as many route lookups.
6. What benefit does NAT64 provide?
- It allows sites to use private IPv6 addresses and translates them to global IPv6 addresses.
- It allows sites to use private IPv4 addresses, and thus hides the internal addressing structure from hosts on public IPv4 networks.
- It allows sites to connect multiple IPv4 hosts to the Internet via the use of a single public IPv4 address.
- It allows sites to connect IPv6 hosts to an IPv4 network by translating the IPv6 addresses to IPv4 addresses.
7. What address translation is performed by static NAT?
- An inside local address is translated to a specified outside local address.
- An inside local address is translated to a specified inside global address.
- An inside local address is translated to a specified outside global address.
- An outside local address is translated to a specified outside global address.
8. Using NAT terminology, what is the address of the source host on a private network as seen from inside the network?
- inside local
- outside global
- outside local
- inside global
9. Which statement accurately describes dynamic NAT?
- It always maps a private IP address to a public IP address.
- It provides an automated mapping of inside local to inside global IP addresses.
- It dynamically provides IP addressing to internal hosts.
- It provides a mapping of internal host names to IP addresses.
10. Why is NAT not needed in IPv6?
- The end-to-end connectivity problems that are caused by NAT are solved because the number of routes increases with the number of nodes that are connected to the Internet.
- Because IPv6 has integrated security, there is no need to hide the IPv6 addresses of internal networks.
- The problems that are induced by NAT applications are solved because the IPv6 header improves packet handling by intermediate routers.
- Any host or user can get a public IPv6 network address because the number of available IPv6 addresses is extremely large.
11. A company designs its network so that the PCs in the internal network are assigned IP addresses from DHCP servers, and the packets that are sent to the Internet are translated through a NAT-enabled router. What type of NAT enables the router to populate the translation table from a pool of unique public addresses, as the PCs send packets through the router to the Internet?
- ARP
- dynamic NAT
- static NAT
- PAT
12. What is a security feature of using NAT on a network?
- denies all internal hosts from communicating outside their own network
- allows internal IP addresses to be concealed from external users
- denies all packets that originate from private IP addresses
- allows external IP addresses to be concealed from internal users
13. When dynamic NAT without overloading is being used, what happens if seven users attempt to access a public server on the Internet when only six addresses are available in the NAT pool?
- The first user gets disconnected when the seventh user makes the request.
- All users can access the server.
- The request to the server for the seventh user fails.
- No users can access the server.
14. A company has been assigned the 203.0.113.0/27 block of IP addresses by the ISP. The company has over 6000 internal devices. What type of NAT would be most appropriate for the employee workstations of the company?
- static NAT
- port forwarding
- dynamic NAT
- PAT off the external router interface
- dynamic NAT overload using the pool of addresses
15. Which version of NAT allows many hosts inside a private network to simultaneously use a single inside global address for connecting to the Internet?
- port forwarding
- PAT
- dynamic NAT
- static NAT
16. Typically, which network device would be used to perform NAT for a corporate environment?
- DHCP server
- Host device
- Router
- Server
- Switch
17. When NAT is used in a small office, which address type or types are typically used for hosts on the local LAN?
- Both private and public IPv4 addresses
- Global public IPv4 addresses
- Internet-routable addresses
- Private IPv4 addresses
18. Which type of NAT maps a single inside local address to a single inside global address?
- Dynamic NAT
- NAT overloading
- Port Address Translation
- Static NAT
19. A network administrator configures the border router with the ip nat inside source list 4 pool NAT-POOL global configuration command. What is required to be configured in order for this particular command to be functional?
- A NAT pool named NAT-POOL that defines the starting and ending public IPv4 addresses
- A VLAN named NAT-POOL that is enabled and active and routed by R1
- An access list named NAT-POOL that defines the private addresses that are affected by NAT
- An access list numbered 4 that defines the starting and ending public IPv4 addresses
- ip nat outside enabled on the interface that connects to the LAN affected by NAT
20. Which configuration would be appropriate for a small business that has the public IPv4 address 209.165.200.225/30 assigned to the external interface on the router that connects to the internet?
- access-list 1 permit 10.0.0.0 0.255.255.255
ip nat pool NAT-POOL 192.168.2.1 192.168.2.8 netmask 255.255.255.240
ip nat inside source list 1 pool NAT-POOL - access-list 1 permit 10.0.0.0 0.255.255.255
ip nat pool NAT-POOL 192.168.2.1 192.168.2.8 netmask 255.255.255.240
ip nat inside source list 1 pool NAT-POOL overload - access-list 1 permit 10.0.0.0 0.255.255.255
ip nat inside source list 1 interface serial 0/0/0 overload - access-list 1 permit 10.0.0.0 0.255.255.255
ip nat pool NAT-POOL 192.168.2.1 192.168.2.8 netmask 255.255.255.240
ip nat inside source list 1 pool NAT-POOL overload
ip nat inside source static 10.0.0.5 209.165.200.225
21. What are two of the required steps to configure PAT? (Choose two.)
- Create a standard access list to define applications that should be translated.
- Define a pool of global addresses to be used for overload translation.
- Define the Hello and Interval timers to match the adjacent neighbor router.
- Define the range of source ports to be used.
- Identify the inside interface.
22. What is the name for the public IPv4 addresses used on a NAT-enabled router?
- Inside global addresses
- Inside local addresses
- Outside global addresses
- Outside local addresses