Prestige 2602HW Series User’s Guide

Figure 77 Firewall: Anti Probing

The following table describes the labels in this screen.

Table 53 Firewall: Anti Probing

LABEL

DESCRIPTION

 

 

Respond to PING

The Prestige does 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 to

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

requests for

unused ports. If you select this option, the Prestige will not respond to port

unauthorized

request(s) for unused ports, thus leaving the unused ports and the Prestige

services.

unseen. By default this option is not selected and the Prestige 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 Prestige 's firewall

 

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

 

mechanism blocks a probing packet, the Prestige 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.

Back

Click Back to return to the previous screen.

 

 

Apply

Click Apply to save your changes back to the Prestige.

 

 

Reset

Click Reset to begin configuring this screen afresh.

 

 

14.12 DOS Thresholds

For DoS attacks, the Prestige uses thresholds to determine when to drop sessions that do not become fully established. These thresholds apply globally to all sessions.

You can use the default threshold values, or you can change them to values more suitable to your security requirements.

Chapter 14 Firewall Configuration

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