2.9 Flashcards
Which method is used by a PAT-enabled router to send incoming packets to the correct inside hosts?
It uses the destination TCP or UDP port number on the incoming packet.
It uses the source IP address on the incoming packet.
It uses the source TCP or UDP port number on the incoming packet.
It uses a combination of the source TCP or UDP port number and the destination IP address on the incoming packet.
It uses the destination TCP or UDP port number on the incoming packet.
- Refer to the exhibit. Which address or addresses represent the inside global address?
10.1.1.2
any address in the 10.1.1.0 network
192.168.0.100
209.165.20.25
209.165.20.25
3 Fill in the blank. Do not use abbreviations.
NAT overload is also known as ______________
Port Address Translation (PAT)
- A network administrator is configuring a static NAT on the border router for a web server located in the DMZ network. The web server is configured to listen on TCP port 8080. The web server is paired with the internal IP address of 192.168.5.25 and the external IP address of 209.165.200.230. For easy access by hosts on the Internet, external users do not need to specify the port when visiting the web server. Which command will configure the static NAT?
R1(config)# ip nat inside source static tcp 192.168.5.25 80 209.165.200.230 8080
R1(config)# ip nat inside source static tcp 192.168.5.25 8080 209.165.200.230 80
R1(config)# ip nat inside source static tcp 209.165.200.230 80 192.168.5.25 8080
R1(config)# ip nat inside source static tcp 209.165.200.230 8080 192.168.5.25 80
R1(config)# ip nat inside source static tcp 192.168.5.25 8080 209.165.200.230 80
- What is defined by the ip nat pool command when configuring dynamic NAT?
the pool of available NAT servers
the range of external IP addresses that internal hosts are permitted to access
the range of internal IP addresses that are translated
the pool of global address
the pool of global address
- Refer to the exhibit. Based on the output that is shown, what type of NAT has been implemented?
dynamic NAT with a pool of two public IP addresses
PAT using an external interface
static NAT with one entry
static NAT with a NAT pool
PAT using an external interface
- What is the primary purpose of NAT?
conserve IPv4 addresses
increase network security
allow peer-to-peer file sharing
enhance network performance
conserve IPv4 addresses
- What is the major benefit of using NAT with Port Address Translation?
It allows external hosts access to internal servers.
It improves network performance for real-time protocols.
It allows many internal hosts to share the same public IPv4 address.
It provides a pool of public addresses that can be assigned to internal hosts.
It allows many internal hosts to share the same public IPv4 address.
- What is a characteristic of unique local addresses?
They allow sites to be combined without creating any address conflicts.
They are designed to improve the security of IPv6 networks.
Their implementation depends on ISPs providing the service.
They are defined in RFC 3927.
They allow sites to be combined without creating any address conflicts.
- A network administrator configures the border router with the command R1(config)# ip nat inside source list 4 pool corp. What is required to be configured in order for this particular command to be functional?
a NAT pool named corp that defines the starting and ending public IP addresses
an access list named corp that defines the private addresses that are affected by NAT
an access list numbered 4 that defines the starting and ending public IP addresses
ip nat outside to be enabled on the interface that connects to the LAN affected by the NAT
a VLAN named corp to be enabled and active and routed by R1
a NAT pool named corp that defines the starting and ending public IP addresses
- Which statement describes IPv6 ULAs?
They conserve IPv6 address space.
They begin with the fe80::/10 prefix.
They are assigned by an ISP.
They are not routable across the internet.
They are not routable across the internet.
- What is the purpose of port forwarding?
Port forwarding allows an external user to reach a service on a private IPv4 address that is located inside a LAN.
Port forwarding allows users to reach servers on the Internet that are not using standard port numbers.
Port forwarding allows an internal user to reach a service on a public IPv4 address that is located outside a LAN.
Port forwarding allows for translating inside local IP addresses to outside local addresses.
Port forwarding allows an external user to reach a service on a private IPv4 address that is located inside a LAN.
- 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?
No users can access the server.
The request to the server for the seventh user fails.
All users can access the server.
The first user gets disconnected when the seventh user makes the request.
The request to the server for the seventh user fails.
- A network engineer has configured a router with the command ip nat inside source list 4 pool corp overload. Why did the engineer use the overload option?
The company has more private IP addresses than available public IP addresses.
The company needs to have more public IP addresses available to be used on the Internet.
The company router must throttle or buffer traffic because the processing power of the router is not enough to handle the normal load of external-bound Internet traffic.
The company has a small number of servers that should be accessible by clients from the Internet.
The company has more private IP addresses than available public IP addresses.
- Match the steps with the actions that are involved when an internal host with IP address 192.168.10.10 attempts to send a packet to and external server at the IP address 209.165.200.254 across a router R1 that running dynamic NAT. (Not all options are used.)
Place the Steps 1-5 to the following options:
- R1 replaces the address 192.168.10.10 with a translated inside global address.
- R1 checks the NAT configuration to determine if this packet should be translated.
- R1 selects an available global address from the dynamic address pool.
- The cost sends packets that request a connection to the server at the address 209.165.200.254
- R1 translates the IP address in the packets from 208.65.200.245 to 192.168.10.10
- If there is no translation entry for this IP address, R1 determines that the source address 192.168.10.10 must be translated.
Place the options in the following order:
– not scored –
step 5 => R1 replaces the address 192.168.10.10 with a translated inside global address.
step 2 => R1 checks the NAT configuration to determine if this packet should be translated.
step 4 => R1 selects an available global address from the dynamic address pool.
step 1 => The cost sends packets that request a connection to the server at the address 209.165.200.254
step 3 => If there is no translation entry for this IP address, R1 determines that the source address 192.168.10.10 must be translated.
