Ch 12 - Fundamentals of Internet Connectivity Flashcards
You are configuring a default route that should direct traffic for unknown networks out of interface Fa 0/0 to a next-hop IP address of 192.168.1.100. Which of the following commands should you use to configure the default route?
a. ip route 255.255.255.255 255.255.255.255 fa 0/0
b. ip route 255.255.255.255 255.255.255.255 192.168.1.100
c. ip route 0.0.0.0 0.0.0.0 fa 0/0
d. ip route 0.0.0.0 0.0.0.0 192.168.1.100
D. A default route is specified with an IP address/mask combination of 0.0.0.0 0.0.0.0. As a best practice, you should point a default route to a next-hop IP address, rather than an Ethernet interface, because specifying an Ethernet interface can generate an excessive number of ARP requests and hurt router performance.
What interface configuration mode command instructs an interface to dynamically obtain its IP address from a DHCP server?
a. ip address 255.255.255.255
b. ip address dynamic
c. ip address dhcp
d. ip address bootp
C. The command used to instruct an interface to obtain its IP address information from a DHCP server is ip address dhcp. All the other options are not valid commands.
Interface Fa 0/0 on your router has obtained an IP address through DHCP. You notice that in addition to an IP address assigned to interface Fa 0/0, your router now has
a default static route configured. What command can you issue to prevent a router from automatically installing a default static route based on default gateway information learned through DHCP?
a. no ip dhcp client request router
b. ip dhcp suppress gateway
c. ip dhcp route local
d. no ip dhcp server response router
A. The no ip dhcp client request router command can be used to prevent a router from automatically installing a static default route based on default gateway information learned from a DHCP server. None of the other options are valid commands.
Interface Fa 0/0 on your router has obtained an IP address through DHCP. You notice that in addition to an IP address assigned to interface Fa 0/0, your router now has a default static route configured. What is the administrative distance (AD) of that route?
a. 0 b. 1
c. 254 d. 255
C. The administrative distance (AD) of a static default route automatically installed in a router based on default gateway information provided by a DHCP server is 254. This makes the default static route a “floating static route,” meaning that it will only be used if another routing source (with a lower AD) does not know of a default static route.
What type of Network Address Translation (NAT) allows a collection of inside local addresses to share a single inside global address, for use when communicating on the Internet?
a. DNAT b. SNAT c. PAT d. MAT
C. Dynamic NAT (DNAT) allows an inside local address to be dynamically associated with an inside global address specified in a pool of available inside global addresses. Static NAT (SNAT) specifies an inside global address to be associated with an inside local address. Port Address Translation (PAT) allows multiple inside local addresses to use a single inside global address, for use when communicating on the Internet. MAT is not a valid variant of NAT.
A laptop inside your network has an IP address of 10.1.1.241. Using NAT, a router translates the 10.1.1.241 private IP address into 198.51.100.54, a public IP address, as the laptop is connecting to a web server on the Internet. The web server has an IP address of 203.0.113.10. What type of address is 10.1.1.241 in this scenario? a. Outside global b. Inside local c. Inside global d. Outside local A laptop inside your network has an IP address of 10.1.1.241. Using NAT, a router translates the 10.1.1.241 private IP address into 198.51.100.54, a public IP address, as the laptop is connecting to a web server on the Internet. The web server has an IP address of 203.0.113.10. What type of address is 203.0.113.10 in this scenario? a. Outside global b. Inside local c. Inside global d. Outside local
B. An outside global address represents a device outside of a network with a globally routable address. In this scenario, the web server’s IP address of 203.0.113.10 would be an outside global address.
An inside local address represents a device inside of a network with an address that is not routable on the public Internet. In this scenario, the laptop’s IP address of 10.1.1.241 would be an inside local address.
An inside global address represents a device on the inside of our network with an address that is a globally routable address. In this scenario, the laptop’s translated address of 198.51.100.54 would be an inside global address.
An outside local address represents a device on the outside of a network that has an address that is not routable on the public Internet. For example, if NAT were being performed at a remote site, the destination device at the remote site would have an outside local address. In the scenario presented in this question, there is no outside local address.
A laptop inside your network has an IP address of 10.1.1.241. Using NAT, a router translates the 10.1.1.241 private IP address into 198.51.100.54, a public IP address, as the laptop is connecting to a web server on the Internet. The web server has an IP address of 203.0.113.10. What type of address is 203.0.113.10 in this scenario?
a. Outside global
b. Inside local
c. Inside global
d. Outside local
A. An outside global address represents a device outside of a network with a globally routable address. In this scenario, the web server’s IP address of 203.0.113.10 would be an outside global address.
An inside local address represents a device inside of a network with an address that is not routable on the public Internet. In this scenario, the laptop’s IP address of 10.1.1.241 would be an inside local address.
An inside global address represents a device on the inside of our network with an address that is a globally routable address. In this scenario, the laptop’s translated address of 198.51.100.54 would be an inside global address.
An outside local address represents a device on the outside of a network that has an address that is not routable on the public Internet. For example, if NAT were being performed at a remote site, the destination device at the remote site would have an outside local address. In the scenario presented in this question, there is no outside local address.
Why is it better to use an IP address as a next-hop rather than an interface?
Because using an interface can generate an excessive number of ARP requests which can lead to poor performance.
What is the default metric on a static route learned from DHCP?
- This is known as a floating-route.
What is NVI?
NAT Virtual Interface.
What is unusual about NVI config?
NVI differs from traditional NAT in that you do not specify ‘ip nat inside’ and ‘ip nat outside’ only ‘ip nat enable on both inside and outside interfaces.
This enables traffic as if it were inside to inside.
T/F: NVI does not support static NAT, only PAT or dynamic NAT.
True.
