Dynamic Dns Setup; Chapter 16 Dynamic Dns Setup; Overview - ZyXEL Communications P-660HN-51 User Manual

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H A P T E R

Dynamic DNS Setup

16.1 Overview

DNS
DNS (Domain Name System) is for mapping a domain name to its corresponding IP address and vice
versa. The DNS server is extremely important because without it, you must know the IP address of a
machine before you can access it.
In addition to the system DNS server(s), each WAN interface (service) is set to have its own static or
dynamic DNS server list. You can configure a DNS static route to forward DNS queries for certain domain
names through a specific WAN interface to its DNS server(s). The Zyxel Device uses a system DNS server
(in the order you specify in the Broadband screen) to resolve domain names that do not match any DNS
routing entry. After the Zyxel Device receives a DNS reply from a DNS server, it creates a new entry for
the resolved IP address in the routing table.
In the following example, the DNS server 168.92.5.1 obtained from the WAN interface ptm0.100 is set to
be the system DNS server. The DNS server 10.10.23.7 is obtained from the WAN interface ppp1.123. You
configure a DNS route for *example.com to have the Zyxel Device forward DNS requests for the domain
name mail.example.com through the WAN interface ppp1.123 to the DNS server 10.10.23.7.
Figure 90 Example of DNS Routing Topology
WAN
LAN
DNS:168.92.5.1
ptm0.100
(Default)
sip.service.com
ppp1.123
mail.example.com
DNS:10.10.23.7
Dynamic DNS
Dynamic DNS allows you to update your current dynamic IP address with one or many dynamic DNS
services so that anyone can contact you (in NetMeeting, CU-SeeMe, etc.). You can also access your
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