Net To Net Technologies SIA2410R User Manual
Net To Net Technologies
40
Configuring NAT Function
To connect to the Internet or any other TCP/IP network, a host must have an
IP address that is unique within that network. The Internet and other large
TCP/IP networks guarantee the uniqueness of addresses by creating central
authorities that assign official IP addresses. However, many local networks
use private IP addresses that are unique only on the local network. To allow a
host with a private address to communicate with the Internet or another
networks that requires an official IP address, the SIA2410R can perform a
service known as Network Address Translation (NAT).
NAT works as follows: When the local host sends packets to the remote
network, the SIA2410R automatically translates the host’s private address on
the local network to an official address on the remote network. When the local
host receives packets from the remote network, SIA2410R automatically
translates the official address on the remote network to the host’s private
address on the local network.
The IP address conversion can be performed in the following three ways:
1> Static Mapping
The SIA2410R establish a one-to-one mapping between the private IP
and public IP.
This translation is used when the connection to the internal network
is attempted from the outside. It is often used when a server on the
LAN needs to be accessed from the WAN.
2> Dynamic Mapping
Usually, this method takes a dynamic n:n translation. The translations
between the local network and the Internet or remote network are
dynamic.
