ZyXEL Communications P-3202HN-Ba, User Manual

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Chapter 16 Remote Management
IAD User’s Guide
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Note: If you want your device to respond to pings and requests for unauthorized
services, you may also need to configure the firewall anti probing settings to
match.
Figure 92 Remote Management > ICMP
The following table describes the labels in this screen.
16.8 SSH
You can use SSH (Secure SHell) to securely access the IAD’s command line
interface.
Specify which interfaces allow SSH access and from which IP address
the access can come.
Table 64 Remote Management > ICMP
LABEL DESCRIPTION
ICMP Internet Control Message Protocol is a message control and error-
reporting protocol between a host server and a gateway to the Internet.
ICMP uses Internet Protocol (IP) datagrams, but the messages are
processed by the TCP/IP software and directly apparent to the
application user.
Respond to
Ping on The IAD will not respond to any incoming Ping requests when Disable is
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 requests for
unauthorized
services Select this option to prevent hackers from finding the IAD by probing for
unused ports. If you select this option, the IAD will not respond to port
request(s) for unused ports, thus leaving the unused ports and the IAD
unseen. If this option is not selected, the IAD 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 IAD's firewall rule
checks before reaching this anti-probing mechanism. Therefore if a
firewall rule stops a probing packet, the IAD reacts based on the firewall
rule to either send a TCP reset packet for a blocked TCP packet (or an
ICMP port-unreachable packet for a blocked UDP packets) or just drop
the packets without sending a response packet.
Apply Click Apply to save your customized settings and exit this screen.
Cancel Click Cancel to begin configuring this screen afresh.