P-660HWP-Dx Support Notes
All contents copyright © 2007 ZyXEL Communications Corporation.
15
locations on the Internet. To use the service, you must first apply an account
from several free Web servers such as http://www.dyndns.org/.
Without DDNS, we always tell the users to use the WAN IP of the
P-660HWP-Dx to reach our internal server. It is inconvenient for the users if
this IP is dynamic. With DDNS supported by the P-660HWP-Dx, 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-660HWP-Dx.
When the ISP assigns the P-660HWP-Dx a new IP, the P-660HWP-Dx
updates this IP to DDNS server so that the server can update its IP-to-DNS
entry. Once the IP-to-DNS table in the DDNS server is updated, the DNS
name for your web server (i.e., www.zyxel.com.tw) is still usable.
10. When do I need DDNS service?
When you want your internal server to be accessed by using DNS name rather
than using the dynamic IP address we can use the DDNS service. The DDNS
server allows to alias a dynamic IP address to a static hostname. Whenever
the ISP assigns you a new IP, the P-660HWP-Dx sends this IP to the DDNS
server for its updates.
11. What is DDNS wildcard? Does the P-660HWP-Dx support DDNS
wildcard?
Some DDNS servers support the wildcard feature which allows the hostname,
*.yourhost.dyndns.org, to be aliased to the same IP address as
yourhost.dyndns.org. This feature is useful when there are multiple servers
inside and you want users to be able to use things such as
www.yourhost.dyndns.org and still reach your hostname.
Yes, the P-660HWP-Dx supports DDNS wildcard that http://www.dyndns.org/
supports. When using wildcard, you simply enter yourhost.dyndns.org in the
Host
field in Menu 1.1 Configure Dynamic DNS.
12. Can the P-660HWP-Dx's SUA handle IPSec packets sent by the IPSec
gateway?
Yes, the P-660HWP-Dx's SUA can handle IPSec ESP Tunneling mode. We
know when packets go through SUA, SUA will change the source IP address
and source port for the host. To pass IPSec packets, SUA must understand
the ESP packet with protocol number 50, replace the source IP address of the
IPSec gateway to the router's WAN IP address. However, SUA should not
change the source port of the UDP packets which are used for key