D-Link DSL-504 User Manual - page 24

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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