SMC Networks WGBR14-N - annexe 1 Manual page 60

Advanced_Firewall
The router provides a tight firewall by virtue of the way NAT works. Unless you configure the
router to the contrary, the NAT does not respond to unsolicited incoming requests on any
port, thereby making your LAN invisible to Internet cyber attackers. However, some network
applications cannot run with a tight firewall. Those applications need to selectively open
ports in the firewall to function correctly. The options on this page control several ways of
opening the firewall to address the needs of specific types of applications. See also Virtual
Server, Port Forwarding, Application Rules, and UPnP for related options.
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