Chapter 4:Configuration
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DNS
A Domain Name System (DNS) contains a mapping table for domain name and IP addresses. On
the Internet, every host has a unique and user-friendly name (domain name) such as
www.helloworld.com and an IP address. An IP address is a 32-bit number in the form of
xxx.xxx.xxx.xxx
, for example 192.168.1.254. You can think of an IP address as a telephone
number for devices on the Internet, and the DNS will allow you to find the telephone number for
any particular domain name. As an IP Address is hard to remember, the DNS converts the friendly
name into its equivalent IP Address.
You can obtain a Domain Name System (DNS) IP address automatically if your ISP has provided it
when you logon, check the
Enable
box. Usually when you choose PPPoE or PPPoA as your WAN
- ISP protocol, the ISP will provide the DNS IP address automatically. You may leave the
configuration field blank.
Alternatively, your ISP may provide you with an IP address of their DNS. If this is the case, you
must enter the DNS IP address manually.
If you choose one of the other three protocols
─
RFC1483 Routed/Bridged and IPoA check with
your ISP, it may provide you with an IP address for their DNS server. You must enter the DNS IP
address if you set the DNS of your PC to the LAN IP address of this router.