ZyXEL Communications P-202 User Manual
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P-202H Plus v2 Support Notes
A filter for blocking the web connections from LAN
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Introduction
If you want to avoid the outbound Web request to trigger a call to the remote web
server, you can configure a call filter set in P-202H Plus v2 to block this packet.
After the call filter is applied, the Web packet will not triggered the call to your ISP
or remote node. However, when the call is trigger by the other packets and the
Internet connection is established, the workstations then are able to access the
Web page.
•
Configuration
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.
o
Create a filter set in Menu 21, e.g., set 1
o
Create three filter rules in Menu 21.1.1, Menu 21.1.2, Menu 21.1.3
Rule 1- block the HTTP packet, TCP (06) protocol with port
number 80
Rule 2- block the DNS packet, TCP (06) protocol with port
number 53
Rule 3- block the DNS packet, UDP (17) protocol with port
number 53
o
Apply the filter set in remote node, Menu 11
•
Create a filter set in Menu 21
Menu 21 - Filter Set Configuration
Filter Filter
Set # Comments Set # Comments
All contents copyright © 2006 ZyXEL Communications Corporation.
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