4 nat, 5 upnp, 5 maintaining your zyxel device – ZyXEL Communications NBG410W3G User Manual
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Chapter 1 Getting to Know Your ZyXEL Device
NBG410W3G Series User’s Guide
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• Set the firewall to block ICMP requests.
• Enable do not respond to requests for unauthorized services.
• If you have a backup gateway (for example, backup Internet access) on your network,
disable the Bypass Triangle Routes feature and enable IP Alias to put your backup
gateway on a different subnet.
• Avoid raising the maximum number of NAT sessions per host unnecessarily as it increases
the possibility of unauthorized connections, such as connections caused by a computer
virus.
1.4.4 NAT
• Enable NAT (Network Address Translation) to make devices on your network “invisible”
to those outside your network (unless you configure port-forwarding rules for them).
• Applications such as games or file-sharing can be configured so they are visible from
other networks by using port-forwarding. Ensure only applications you want are
configured to port-forward.
See
for instructions on these measures.
1.4.5 UPnP
• Disable UPnP (Universal Plug and Play) unless you specifically want applications (for
example, games or file-sharing applications) on your network to pass through your
firewall unchecked.
See
for instructions on this measure.
1.5 Maintaining Your ZyXEL Device
Do the following things regularly to keep your ZyXEL Device running.
• Check the ZyXEL website (www.zyxel.com.tw) regularly for new firmware for your
ZyXEL Device.
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Ensure you download the correct firmware for your model.
• Back up the configuration (and make sure you know how to restore it). Restoring an
earlier working configuration may be useful if the device becomes unstable or even
crashes. If you forget your password, you will have to reset the ZyXEL Device to its
factory default settings. If you backed up an earlier configuration file, you would not have
to totally re-configure the ZyXEL Device. You could simply restore your last
configuration.