Filter Example
A filter for blocking the web service
Before configuring a filter, you need to know the following information:
1. The outbound packet type (protocol & port number)
2. The source IP address
Generally, the outbound packets for Web service could be as following:
a. HTTP packet, TCP (06) protocol with port number 80
b. DNS packet, TCP (06) protocol with port number 53 or
c. DNS packet, UDP (17) protocol with port number 53
For all workstation on the LAN, the source IP address will be 0.0.0.0. Otherwise, you have to enter an IP Address for the workstation you want to block. See the procedure for configuring this filter below.
1. Create a filter set in Menu 21
Menu 21 - Filter Set Configuration
Filter
Filter Enter Filter Set Number to Configure= 1 Edit Comments=
Press ENTER to Confirm or ESC to Cancel: |
2. Rule one for (a). http packet, TCP(06)/Port number 80
Menu 21.1.1 - TCP/IP Filter Rule
Filter #: 1,1
Press ENTER to Confirm or ESC to Cancel: |
3.Rule 2 for (b).DNS request, TCP(06)/Port number 53
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,2
Press ENTER to Confirm or ESC to Cancel: |
4. Rule 3 for (c). DNS packet UDP(17)/Port number 53
Menu 21.1.2 - TCP/IP Filter Rule
Filter #: 1,2
Press ENTER to Confirm or ESC to Cancel: |
5. After the three rules are completed, you will see the rule summary in Menu 21.
Menu 21.1 - Filter Rules Summary # A
Type
Filter Rules M m n
|
6. Apply the filter set to the 'Output Protocol Filter Set' in the remote
node setup
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