3e Technologies International 3e-525A, User Manual

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3e-525A Wireless Access Point
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Chapter 4: Configure as gateway
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Virtual Server
In order to protect the Private Network, the built-in NAT firewall
filters out traffic to the private network. Since all clients on the Private
Network are normally not visible to outside users, the virtual server func-
tion allows some clients on the Private Network to be accessed by outside
users by configuring the application mapping function offered on this
page. Certain well known applications use specific TCP ports, such as
Telnet (port 23), FTP (port 21), and Web server (port 80). Client computers
on the Private LAN can host these applications, and allow users from the
Internet to access these applications hosted on the virtual servers.
This is done by mapping virtual servers to private IP addresses,
according to the specific TCP port application. As the planning table
below shows, we have identified a Telnet (port 23) virtual server for
private IP 192.168.15.56, a SMTP Mail (port 25) virtual server for pri-
vate IP 192.168.15.33, and a Web (port 80) virtual server for private IP
192.168.15.64. For example, all Internet requests to the gateway for SMTP
Mail services (port 25) to the WAN IP address will redirected to the Pri-