Figure
Network Address Translation (NAT/masquerading)
The CyberGuard SG appliance can utilize IP Masquerading (a simple form of Network Address Translation, or NAT) where PCs on the local network effectively share a single external IP address. Masquerading allows insiders to get out, without allowing outsiders in. By default, the Internet port is setup to masquerade.
Masquerading has the following advantages:
∙Added security because machines outside the local network only know the gateway address.
∙All machines on the local network can access the Internet using a single ISP account.
∙Only one public IP address is used and is shared by all machines on the local network. Each machine has its own private IP address.
Note
It is strongly recommended that you leave Enable NAT on Internet Interface checked.
On SG570 and SG575 models, you may set up masquerading relationships between the LAN, DMZ and Internet ports.
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