D6200 WiFi DSL Modem Router
To specify a trusted computer:
1.
In the Trusted IP Address field, enter the IP address.
2.
Click Apply.
Firewall Rules
Services are functions performed by server computers at the request of client computers. For example, web servers serve web pages, time servers serve time and date information, and game hosts serve data about other players’ moves. When a computer on the Internet sends a request for service to a server computer, the requested service is identified by a service or port number. This number appears as the destination port number in the transmitted IP packets. For example, a packet that is sent with the destination port number 80 is an HTTP
(web server) request.
The service numbers for many common protocols are defined by the Internet Engineering
Task Force (IETF at http://www.ietf.org/ ) and published in RFC1700, “Assigned Numbers.”
Service numbers for other applications are typically chosen from the range 1024–65535 by the authors of the application. Although the WiFi DSL modem router already holds a list of many service port numbers, you are not limited to these choices. You can often determine port number information by contacting the publisher of the application, by asking user groups or newsgroups, or by searching.
Note: This feature is for advanced administrators only! Incorrect configuration can cause serious problems.
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To create firewall rules:
1.
Select ADVANCED > Security > Firewall Rules.
The Firewall Rules screen lists all firewall rule settings. The default rules allow all outgoing traffic and block all incoming traffic.
2.
Under Outbound Services, click Add.
3.
Configure the following settings:
• Service. Select the service or application to be covered by this rule.
If the service or application you want does not appear in the list, you have to define it
as described in Add Custom Services to Allow or Block on page 89.
• Action. Select the action you want for traffic covered by this rule:
- BLOCK always. Always block the traffic covered by this rule.
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- BLOCK by schedule, otherwise Allow. Allow the traffic covered by this rule, unless it is blocked according to the schedule specified on the Schedule screen.
See Schedule for Firewall Rules on page 90.
- ALLOW always. Always allow the traffic covered by this rule.
This selection is the default setting.
- ALLOW by schedule, otherwise Block. Block the traffic covered by this rule, unless it is blocked according to the schedule specified on the Schedule screen.
See Schedule for Firewall Rules on page 90.
ALLOW rules are useful only when the traffic is already covered by a BLOCK rule.
You would use these rules when you want to allow a subset of traffic that is blocked by another rule.
• LAN Users.
These settings determine which computers on your network are affected by this rule, based on their source (LAN) IP address. Select the option you want:
- Any. All local IP addresses are covered by this choice.
- Address range. You have to provide the Start and End fields when this option is selected.
- Single address. Enter the required address in the Start field.
• WAN Servers.
These settings determine which Internet locations are covered by the rule, based on their destination (WAN) IP address. Select the option you want:
- Any. All Internet IP addresses are covered by this choice.
- Address range. You have to provide the Start and End fields when this option is selected.
- Single address. Enter the required address in the Start field.
• Log.
This setting determines whether traffic covered by this rule is logged. Select the action you want:
• Always. Always log traffic that is covered by this rule, whether it matches or not.
(This feature is useful when you are debugging your rules.)
• Never. Never log traffic covered by this rule, whether it matches or not.
• Click Apply.
Your changes take effect.
4.
To allow or block an inbound service and to set up inbound firewall rules for gaming or other applications, under Inbound Services, click the here link.
You are redirected to the Port Forwarding/Port Triggering screen as described in Port
Forwarding and Port Triggering on page 114.
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