Security Settings
37
N150 WiFi Router (N150R)
Firewall Rules to Control Network Access
Your router has a firewall that blocks unauthorized access to your wireless network and
permits authorized inbound and outbound communications. Authorized communications are
established according to inbound and outbound rules. The firewall has the following two
default rules. You can create custom rules to further restrict the outbound communications or
more widely open the inbound communications:
•
Inbound
. Block all access from outside except responses to requests from the LAN side.
•
Outbound
. Allow all access from the LAN side to the outside.
Inbound Rules (Port Forwarding)
Because the router uses Network Address Translation (NAT), your network presents only
one IP address to the Internet, and outside users cannot directly address any of your local
computers. However, by defining an inbound rule you can make a local server (for example,
a Web server or game server) visible and available to the Internet.
The rule tells the router to direct inbound traffic for a particular service to one local server
based on the destination port number. This is also known as port forwarding. Allowing
inbound services opens holes in your firewall. Enable only those ports that are necessary for
your network. The following are two examples of inbound rules.
Note:
Some residential broadband ISP accounts do not let you run server
processes (such as a Web or FTP server) from your location. Your
ISP might periodically check for servers and suspend your account
if it discovers any active services at your location. If you are unsure,
refer to the acceptable use policy of your ISP.
Outbound Rules (Service Blocking)
You can block computers on your local network from using certain Internet services. This is
called service blocking or port filtering. You can add an outbound rule to block Internet
access from a local computer based on the computer, Internet site, time of day, and type of
service.