ZyWALL 2 Series User’s Guide

 

 

Table 17-8 Security

 

 

 

 

 

LABEL

DESCRIPTION

 

 

 

 

 

 

Respond to Ping

The ZyWALL will not respond to any incoming Ping requests when Disable is

 

 

on

selected. Select LAN to reply to incoming LAN Ping requests. Select WAN to reply to

 

 

 

incoming WAN Ping requests. Otherwise select LAN & WAN to reply to both incoming

 

 

 

LAN and WAN Ping requests.

 

 

 

 

 

 

Do not respond

Select this option to prevent hackers from finding the ZyWALL by probing for unused

 

 

to requests for

ports. If you select this option, the ZyWALL will not respond to port request(s) for

 

 

unauthorized

unused ports, thus leaving the unused ports and the ZyWALL unseen. By default this

 

 

services

option is not selected and the ZyWALL will reply with an ICMP Port Unreachable

 

 

 

packet for a port probe on its unused UDP ports, and a TCP Reset packet for a port

 

 

 

probe on its unused TCP ports.

 

 

 

Note that the probing packets must first traverse the ZyWALL 's firewall mechanism

 

 

 

before reaching this anti-probing mechanism. Therefore if the firewall mechanism

 

 

 

blocks a probing packet, the ZyWALL reacts based on the firewall policy, which by

 

 

 

default, is to send a TCP reset packet for a blocked TCP packet. You can use the

 

 

 

command "sys firewall tcprst rst [onoff]" to change this policy. When the firewall

 

 

 

mechanism blocks a UDP packet, it drops the packet without sending a response

 

 

 

packet.

 

 

 

 

 

 

Apply

Click Apply to save your customized settings and exit this screen.

 

 

 

 

 

 

Reset

Click Reset to begin configuring this screen afresh.

 

 

 

 

 

Remote Management Screens

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