In the configuration of NAT, what does the keyword overload signify?
A.
When bandwidth is insufficient, some hosts will not be allowed to access network translation.
B.
The pool of IP addresses has been exhausted.
C.
Multiple internal hosts will use one IP address to access external network resources.
D.
If the number of available IP addresses is exceeded, excess traffic will use the specified
address pool.
NAT Overload, also known as PAT (Port Address Translation) is essentially NAT with the added feature of TCP/UDP ports translation. The main purpose of NAT is to hide the IP address (usually private) of a client in order to reserve the public address space.
0
0
For example a complete network with 100 hosts can have 100 private IP addresses and still be visible to the outside world (internet) as a single IP address. Other benefits of NAT include security and economical usage of the IP address ranges at hand.
The first step in any NAT configuration is to define the inside and outside interfaces. It is imperative that we define the these interfaces for NAT overload to function.
Set the fast ethernet 0/0 interface as the inside interface:
R1# configure terminal
R1(config)# interface fastethernet0/0
R1(config-if)# ip nat inside
Next step is to set the serial interface S0/0 as the outside interface:
R1(config-if)# interface serial0/0
R1(config-if)# ip nat outside
R1(config-if)# exit
0
0
‘Overloading’ means that the single public IP assigned to your router can be used by multiple internal hosts concurrently. This is done by translating source UDP/TCP ports in the packets and keeping track of them within the translation table kept in the router (R1 in our case). This is a typical NAT configuration for almost all of today’s networks
NAT (Network Address Translation) is a method that allows the translation (modification) of IP addresses while packets/datagrams are traversing the network. NAT Overload, also known as PAT (Port Address Translation) is essentially NAT with the added feature of TCP/UDP ports translation.
The main purpose of NAT is to hide the IP address (usually private) of a client in order to reserve the public address space. For example a complete network with 100 hosts can have 100 private IP addresses and still be visible to the outside world (internet) as a single IP address. Other benefits of NAT include security and economical usage of the IP address ranges at hand.
0
0