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4.5 Forwarding Rules

4.5.1 Virtual Server

22

This product

’

s NAT firewall filters out unrecognized packets to protect your Intranet, so all hosts

behind this product are invisible to the outside world. If you wish, you can make some of them

accessible by enabling the Virtual Server Mapping.

A virtual server is defined as a

Service Port

, and all requests to this port will be redirected to the

computer specified by the

Server IP

.

Virtual Server

can work with

Scheduling Rules

, and give

user more flexibility on Access control. For Detail, please refer to

Scheduling Rule

.

For example, if you have an FTP server (port 21) at 192.168.123.1, a Web server (port 80) at

192.168.123.2, and a VPN server at 192.168.123.6, then you need to specify the following virtual

server mapping table:

Service Port

Server IP

Enable

21

192.168.123.1

V

80

192.168.123.2

V

1723

192.168.123.6

V

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4.5.2 Special AP

Some applications require multiple connections, like Internet games, Video conferencing, Internet

telephony, etc. Because of the firewall function, these applications cannot work with a pure NAT router.

The

Special Applications

feature allows some of these applications to work with this product. If the

mechanism of Special Applications fails to make an application work, try setting your computer as the

DMZ

host instead.

1.

Trigger

: the outbound port number issued by the application..

2.

Incoming Ports

: when the trigger packet is detected, the inbound packets sent to the specified

port numbers are allowed to pass through the firewall.

This product provides some predefined settings Select your application and click

Copy

to

to add the

predefined setting to your list.

Note! At any given time, only one PC can use each Special Application tunnel.

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4.5.3 Miscellaneous Items

IP Address of DMZ Host

DMZ (DeMilitarized Zone) Host is a host without the protection of firewall. It allows a computer to be

exposed to unrestricted 2-way communication for Internet games, Video conferencing, Internet

telephony and other special applications.

NOTE: This feature should be used only when needed.

Non-standard FTP port

You have to configure this item if you want to access an FTP server whose port number is not 21. This

setting will be lost after rebooting.

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4.6 Security Settings