Wireless Gateway Series User's Guide

ZyAIR Wireless Gateway Series User’s Guide
Remote Management 13-13
Table 13-8 Security
LABEL DESCRIPTION
Do not respond
to requests for
unauthorized
services
Select this option to prevent hackers from finding the ZyAIR by probing for unused
ports. If you select this option, the ZyAIR will not respond to port request(s) for unused
ports, thus leaving the unused ports and the ZyAIR unseen. By default this option is
not selected and the ZyAIR 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 ZyAIR's firewall mechanism
before reaching this anti-probing mechanism. Therefore if the firewall mechanism
blocks a probing packet, the ZyAIR 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 [on|off]" 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 changes back to the ZyAIR.
Reset
Click Reset to begin configuring this screen afresh.