Network administrator configures
A network
administrator wants to examine the active NAT translations on a border router.
Which command would perform the task?
·
Router# show ip nat
translations
Refer to curriculum topic: 9.3.1
The clear ip nat translations command clears all dynamic address translation
entries from the NAT translation table. The debug ip nat command is used to
verify the operation of NAT. The show ip nat statistics command displays
information about the total number of active translations, NAT configuration
parameters, the number of addresses in the pool, and the number that have been
allocated. The show ip nat translations command displays the active NAT
translations.
A network
administrator configures the border router with the command R1(config)# ip nat
inside source list 4 pool corp. Which ACL is required to be configured in order
for this command to function?
·
an access list that is
numbered 4 that defines the private addresses that are affected by NAT
Refer to curriculum topic: 9.2.2
In order for the ip nat inside source list 4 pool corp command to work, the
following procedure needs to be used:
1. Create an access list that defines the private IP addresses affected by NAT.
2. Establish a NAT pool of starting and ending public IP addresses using the ip
nat pool command.
3. Use the ip nat inside source list command to associate the access list with
the NAT pool.
4. Apply NAT to internal and external interfaces by using the ip nat inside and
ip nat outside commands.
Refer to the exhibit.
Router R2 is configured with static NAT. Place in order the steps that occur
when the client accesses the web server through the router. (Not all options
are used.)
·
The client uses the
inside global address of the web server as the destination address to send a
packet to the web server.
2. R2 receives the packet on its outside interface, then checks and locates the
destination address in its NAT table.
3. R2 replaces the inside global address with the inside local address of the
web server and forwards the packet to the web server.
4. The web server uses the outside global address of the client as the
destination address when responding.
5. R2 receives the packet from the web server. R2 checks the NAT table, then
translates the source address of the web server into an inside global address
and forwards the packet.
Refer to curriculum topic: 9.2.1
Static NAT translations are usually used when clients on the outside network
(Internet) need to reach servers on the inside (internal) network. The process
begins with the client trying to communicate with the web server by the use of
the inside global address of the web server as the destination address. The
router receives this on its outside interface, consults its NAT table, locates
the destination address, and forwards the packet to the web server on the
internal network via its inside local address. The web server response goes to
the router, which replaces the web server inside local address with the global
address (NAT table) and forwards the packet to the client on its external
interface.
Typically, which
network device would be used to perform NAT for a corporate environment?
·
router
Refer to curriculum topic: 9.1.1
Typically, the translation from private IP addresses to public IP addresses is
performed on routers in corporate environments. In a home environment, this
device might be an access point that has routing capability or the DSL or cable
router.
Refer to the exhibit.
The NAT configuration applied to the router is as follows:
ERtr(config)# access-list 1 permit 10.0.0.0 0.255.255.255
ERtr(config)# ip nat pool corp 209.165.201.6 209.165.201.30 netmask
255.255.255.224
ERtr(config)# ip nat inside source list 1 pool corp overload
ERtr(config)# ip nat inside source static 10.10.10.55 209.165.201.4
ERtr(config)# interface gigabitethernet 0/0
ERtr(config-if)# ip nat inside
ERtr(config-if)# interface serial 0/0/0
ERtr(config-if)# ip nat outside
Based on the configuration and the output shown, what can be determined about
the NAT status within the organization?
·
Not enough information
is given to determine if both static and dynamic NAT are working.
Refer to curriculum topic: 9.3.1
There is not enough information given because the router might not be attached
to the network yet, the interfaces might not have IP addresses assigned yet, or
the command could have been issued in the middle of the night. The output does
match the given configuration, so no typographical errors were made when the
NAT commands were entered.
Refer to the exhibit.
Router R1 is configured for PAT. What is a possible reason that the addresses
in the network are not translated?
·
Access-list 1 is
misconfigured.
Refer to curriculum topic: 9.2.3
The wildcard mask in the access control entry does not allow traffic from both
the 192.168.11.0/24 and the 192.168.12.0/24 networks. The correct configuration
command is R1(config)# access-list 1 permit 192.168.0.0 0.0.255.255.
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?
·
dynamic NAT
Refer to curriculum topic: 9.1.2
ARP is the address resolution protocol and is used to obtain the MAC address of
the destination device. Static NAT is a one-to-one mapping between the local
and global addresses of a device. PAT, otherwise known as NAT overload, maps
multiple private IP addresses to a singular public address or group of
addresses. Dynamic NAT uses a pool of public IP addresses and assigns them to
requesting devices on a first-come, first-served basis. In the case of dynamic
NAT, each device would have a unique public IP address from the pool of public
IP addresses as the source IP address in the packets that they send.
What is the purpose of
entering the command ip nat inside source static tcp 192.168.10.2 80
209.165.200.223 8080 at the global configuration prompt?
It binds the inside
local address and local port to the specified inside global address and global
port.
·
Refer to curriculum topic: 9.2.4
The displayed command establishes static translation between an inside local
address and local port and an inside global address and global port. In order
to identify the inside NAT interface, the command Router(config-if)# ip nat
inside would have to be entered on the respective interface.
What is correct in
relation to NAT for IPv6?
It is a temporary
mechanism to assist in the migration from IPv4 to IPv6.
·
Refer to curriculum topic: 9.2.5
NAT for IPv6 is a temporary measure to aid in the move from IPv4 to IPv6. NAT64
is replacing NAT-PT. Dual stack is a method for running IPv4 and IPv6 on the
same network.
Which statement
accurately describes dynamic NAT?
·
It provides an
automated mapping of inside local to inside global IP addresses.
Refer to curriculum topic: 9.2.2
Dynamic NAT provides a dynamic mapping of inside local to inside global IP
addresses. NAT is merely the one-to-one mapping of one address to another
address without taking into account whether the address is public or private.
DHCP is automatic assignment of IP addresses to hosts. DNS is mapping host
names to IP addresses.
Refer to the exhibit.
Router R1 is configured with static NAT. Addressing on the router and the web
server are correctly configured, but there is no connectivity between the web
server and users on the Internet. What is a possible reason for this lack of
connectivity?
·
The router NAT
configuration has an incorrect inside local address.
Refer to curriculum topic: 9.2.1
The correct syntax would be R1(config)# ip nat inside source static
192.168.11.11 209.165.200.1. (The inside local address is 192.168.11 and the
inside global address is 209.165.200.1.)
USA 
India