NAT

addresses. In other words, depending on the requested service (TCP/UDP port number), the Barricade redirects the external service request to the appropriate server (located at another internal IP address.)

For example, if you set Type/Public Port to TCP/80 (HTTP or Web) and the Private IP/Port to 192.168.2.2/80, then all HTTP requests from outside users will be transferred to 192.168.2.2 on port 80. Therefore, by just entering the IP Address provided by the ISP, Internet users can access the service they need at the local address to which you redirect them.

The more common TCP service ports include:

HTTP: 80, FTP: 21, Telnet: 23, and POP3: 110.

Note: The WAN interface should have a fixed IP address to best utilize this function. If your ISP only provides dynamic IP addresses, a search for “free dynamic IP” on any major search engine will turn up tools that will allow you to use the same domain name even though your IP address changes each time you log in to the ISP.

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SMC Networks SMC7404BRA EU manual 4-29, The more common TCP service ports include