Advanced Filter/Firewall - D-Link DSL-504 User Manual

DSL-504 ADSL Router User's Guide
Port Redirection Window
The Port Redirection feature of the Router is used in conjunction with NAT to
improve security and efficiency. For example, this can be used to direct HTTP
packets to a designated HTTP server as a form of firewall protection for the LAN.
Other common applications might include directing incoming SMTP packets to
an Email server. Click Add in the Port Redirection window to access the Redirect
Port window pictured below.
Redirect Port Window
The Redirect Port window presents five entry fields. The first field, Comment
can be used to assign an appropriate name to the new route, for our example we
will use the name HTTP Server. In the Internet Port field enter the designated
TCP or UDP protocol port number for the particular protocol packet you wish to
redirect. In our example an incoming HTTP packets use port 80. The local port is
the port used by the designated host on the LAN. In this case an HTTP server,
conventionally port 8080 is used for this purpose. Choose the protocol either TCP
or UDP from the pull-down Protocol menu. HTTP is defined within TCP. In the
Local Computer field supply the IP address of the local designated host
computer or device. Using our example you would enter the IP address of the
HTTP server.

Advanced Filter/Firewall

The Router features IP address filtering for improved network security. Incoming
or outgoing IP packets can be blocked and discarded. This allows you to restrict
communications from specific outside global IP addresses from entering your
network. You may also use it to restrict any specific host on the LAN from
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