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Firewall
NAT
NAT (Network Address Translation or Network Address Translator) is the
translation of an Internet Protocol address (IP address) used within one
network to a different IP address known within another network. One
network is designated as the
inside
network and the other, as the
outside
network
. Typically, a company maps its local inside network addresses to
one or more global outside IP addresses and un-maps the global IP
addresses on incoming packets back into local IP addresses. This helps
ensure security since each outgoing or incoming request must go
through a translation process that also offers the opportunity to qualify or
authenticate the request or match it to a previous request. NAT also
conserves on the number of global IP addresses that a company needs
and it lets the company use a single IP address in its communication with
the world.
Adding a NAT item
Service Name:
The NAT entry name
Service Type:
The protocol used TCP or UDP or BOTH
Outside Starting Port:
Starting port number of the WAN incoming traffic
Inside Start Port:
Inside LAN start port number
Port Numbers:
Number of ports to be forwarded
Server IP Address:
LAN IP address that will be used for NAT
functionality.
Example:
