P-662H/HW-D Series User’s Guide

The following table describes the labels in this screen.

Table 64 Firewall: General

LABEL

DESCRIPTION

 

 

Active Firewall

Select this check box to activate the firewall. The ZyXEL Device performs access

 

control and protects against Denial of Service (DoS) attacks when the firewall is

 

activated.

Bypass Triangle

Select this check box to have the ZyXEL Device firewall permit the use of triangle

Route

route topology on the network. See the appendix for more on triangle route

 

topology.

 

Note: Allowing asymmetrical routes may let traffic from the WAN go

 

directly to a LAN computer without passing through the

 

router. See Appendix P on page 481 for more on triangle

 

route topology and how to deal with this problem.

 

 

Packet Direction

This is the direction of travel of packets.

 

Firewall rules are grouped based on the direction of travel of packets to which they

 

apply. For example, LAN to LAN / Router means packets traveling from a

 

computer/subnet on the LAN to either another computer/subnet on the LAN

 

interface of the ZyXEL Device or the ZyXEL Device itself.

Default Action

Use the drop-down list boxes to select the default action that the firewall is take on

 

packets that are traveling in the selected direction and do not match any of the

 

firewall rules.

 

Select Drop to silently discard the packets without sending a TCP reset packet or

 

an ICMP destination-unreachable message to the sender.

 

Select Reject to deny the packets and send a TCP reset packet (for a TCP packet)

 

or an ICMP destination-unreachable message (for a UDP packet) to the sender.

 

Select Permit to allow the passage of the packets.

 

 

Log

Select the check box to create a log (when the above action is taken) for packets

 

that are traveling in the selected direction and do not match any of your customized

 

rules.

Expand...

Click this button to display more information.

 

 

Basic...

Click this button to display less information.

 

 

Apply

Click Apply to save your changes back to the ZyXEL Device.

 

 

Cancel

Click Cancel to begin configuring this screen afresh.

11.6 Firewall Rules Summary

Note: The ordering of your rules is very important as rules are applied in turn.

Refer to Section 10.1 on page 169 for more information.

Click Security > Firewall > Rules to bring up the following screen. This screen displays a list of the configured firewall rules. Note the order in which the rules are listed.

Chapter 11 Firewall Configuration

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