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3. MAC Filtering

This page enables you to enter the MAC address of specific PCs on your LAN that you do not wish to

have outbound access to the WAN. As with IP filtering, these PCs can still communicate with each other

through the gateway, but packets they send to WAN addresses are blocked.

Fig.2-23 Gateway\Advanced\MAC Filtering

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4. Port Filtering

This page allows you to enter ranges of destination ports (applications) that you don’t want your LAN

PCs to send packets to. Any packets your LAN PCs send to these destination ports will be blocked. For

example, you could block access to worldwide web browsing (http = port 80) but still allow email service

(SMTP port 25 and POP-3 port 110). To enable port filtering, set Start Port and End Port for each range,

and click Apply. To block only one port, set both Start and End ports with the same value.

Fig.2-24 Gateway\Advanced\Port Filtering

For example :

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To block HTTP (port 80) browse and restrict mail send from POP-3(port 110), setting as following

Fig.2-25 Gateway\Advanced\Port Filtering

Setting port value, block protocol (Both for TCP & UDP), check

‘

Enable

’

then apply.

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5. Forwarding

For LAN



WAN communications, the gateway normally only allows you to originate an IP connection

with a PC on the WAN; it will ignore attempts of the WAN PC to originate a connection onto your PC.

This protects you from malicious attacks from outsiders. However, sometimes you may wish for anyone

outside to be able to originate a connection to a particular PC on your LAN if the destination port

(application) matches one you specify.

Fig.2-26 Gateway\Advanced\Forwarding

Press

‘

Create Ipv4

’

button you will see follow options shows on the page. To specify rules, choose

S

ervice Name

or

Port

number range to set up. IP Address 0.0.0.0 means allow all IP address.

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Fig.2-27 Gateway\Advanced\Forwarding setting

This page allows you to specify up to rules. For example, to specify that outsiders should have access to

an FTP server you have running at 192.168.0.5, create a rule with that address and Start Port =20 and End

Port =21 (FTP port ranges) and Protocol = TCP (FTP runs over TCP and the other transport protocol,

UDP), and click Apply. This will cause inbound packets that match to be forwarded to that PC rather than

blocked. As these connections are not tracked, no entry is made for them in the Connection Table. The

same IP address can be entered multiple times with different ports.