ZyXEL Communications P-661H-61, Manual

Page: 109 / 404

Chapter 5 Broadband
P-661HNU-Fx User’s Guide
109
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.
1
The ISP tells you the DNS server addresses, usually in the form of an information
sheet, when you sign up. If your ISP gives you DNS server addresses, manually
enter them in the DNS server fields.
2
If your ISP dynamically assigns the DNS server IP addresses (along with the
ZyXEL Device’s WAN IP address), set the DNS server fields to get the DNS server
address from the ISP.