User`s manual

P-660R-F1 Support Notes
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All contents copyright © 2011 ZyXEL Communications Corporation.
(2) Internet Access with an Internal Server
In this case, we do exactly as the figure (use the convenient pre-configured SUA
Only set) and also go to Web Configurator, Advanced Setup, Network -> NAT ->
Port Forwarding to specify the Internet Server behind the NAT as below:
5. Using the Dynamic DNS (DDNS)
What is DDNS?
The DDNS service, an IP Registry provides a public central database where
information such as email addresses, hostnames; IPs etc. can be stored and
retrieved. This solves the problems if your DNS server uses an IP associated with
dynamic IPs.
Without DDNS, we always tell the users to use the WAN IP of the P-660R-F1 to
access the internal server. It is inconvenient for the users if this IP is dynamic.
With DDNS supported by the P-660R-F1, you apply a DNS name (e.g.,
www.zyxel.com.tw) for your server (e.g., Web server) from a DDNS server. The
outside users can always access the web server using the www.zyxel.com.tw
regardless of the WAN IP of the P-660R-F1. When the ISP assigns the P-660R-F1
a new IP, the P-660R-F1 must inform the DDNS server the change of this IP so
that the server can update its IP -to-DNS entry. Once the IP-to-DNS table in the