NETGEAR ADSL Firewall Router DG834 - Manual (Page 53)

Reference Manual for the ADSL Firewall Router DG834
Protecting Your Network 4-9
202-10005-05, June 2005
• If the IP address of the local server computer is assigned by DHCP, it may change when the
computer is rebooted. To avoid this, use the Reserved IP address feature in the LAN IP menu
to keep the computer’s IP address constant.
• Local computers must access the local server using the computer’s local LAN address
(192.168.0.11 in the example in
Figure 4-6 above). Attempts by local computers to access the
server using the external WAN IP address will fail.
Outbound Rules (Service Blocking)
The DG834 allows you to block the use of certain Internet services by computers on your network.
This is called service blocking or port filtering. You can define an outbound rule to block Internet
access from a local computer based on:
• IP address of the local computer (source address)
• IP address of the Internet site being contacted (destination address)
• Time of day
• Type of service being requested (service port number)
Following is an application example of outbound rules:
Outbound Rule Example: Blocking Instant Messenger
If you want to block Instant Messenger usage by employees during working hours, you can create
an outbound rule to block that application from any internal IP address to any external address
according to the schedule that you have created in the Schedule menu. You can also have the router
log any attempt to use Instant Messenger during that blocked period.