ZyXEL Communications P-660HNU-F1 User Manual page 104

Chapter 5 Broadband
and is used by IP multicast computers. The address 224.0.0.1 is used for query messages and is
assigned to the permanent group of all IP hosts (including gateways). All hosts must join the
224.0.0.1 group in order to participate in IGMP. The address 224.0.0.2 is assigned to the multicast
routers group.
At start up, the ZyXEL Device queries all directly connected networks to gather group membership.
After that, the ZyXEL Device periodically updates this information.
DNS Server Address Assignment
Use Domain Name System (DNS) to map a domain name to its corresponding IP address and vice
versa, for instance, the IP address of www.zyxel.com is 204.217.0.2. The DNS server is extremely
important because without it, you must know the IP address of a computer before you can access
it.
The ZyXEL Device can get the DNS server addresses in the following ways.
The ISP tells you the DNS server addresses, usually in the form of an information sheet, when you
1
sign up. If your ISP gives you DNS server addresses, manually enter them in the DNS server fields.
If your ISP dynamically assigns the DNS server IP addresses (along with the ZyXEL Device's WAN IP
2
address), set the DNS server fields to get the DNS server address from the ISP.
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ADSL Series User's Guide