ZyXEL Communications VSG1432-B101 Series User Manual

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Chapter 8 Home Networking
VSG1432-B101 Series User’s Guide
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• 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, enter them in the DNS Server fields in the DHCP Setup screen.
• Some ISPs choose to disseminate the DNS server addresses using the DNS 
server extensions of IPCP (IP Control Protocol) after the connection is up. If 
your ISP did not give you explicit DNS servers, chances are the DNS servers are 
conveyed through IPCP negotiation. The ZyXEL Device supports the IPCP DNS 
server extensions through the DNS proxy feature.
Please note that DNS proxy works only when the ISP uses the IPCP DNS server 
extensions. It does not mean you can leave the DNS servers out of the DHCP 
setup under all circumstances. If your ISP gives you explicit DNS servers, make 
sure that you enter their IP addresses in the DHCP Setup screen.
8.7.4  LAN TCP/IP 
The ZyXEL Device has built-in DHCP server capability that assigns IP addresses 
and DNS servers to systems that support DHCP client capability.
IP Address and Subnet Mask
Similar to the way houses on a street share a common street name, so too do 
computers on a LAN share one common network number.
Where you obtain your network number depends on your particular situation. If 
the ISP or your network administrator assigns you a block of registered IP 
addresses, follow their instructions in selecting the IP addresses and the subnet 
mask.
If the ISP did not explicitly give you an IP network number, then most likely you 
have a single user account and the ISP will assign you a dynamic IP address when 
the connection is established. If this is the case, it is recommended that you select 
a network number from 192.168.0.0 to 192.168.255.0 and you must enable the 
Network Address Translation (NAT) feature of the ZyXEL Device. The Internet 
Assigned Number Authority (IANA) reserved this block of addresses specifically for 
private use; please do not use any other number unless you are told otherwise. 
Let's say you select 192.168.1.0 as the network number; which covers 254 
individual addresses, from 192.168.1.1 to 192.168.1.254 (zero and 255 are 
reserved). In other words, the first three numbers specify the network number 
while the last number identifies an individual computer on that network.
Once you have decided on the network number, pick an IP address that is easy to 
remember, for instance, 192.168.1.1, for your ZyXEL Device, but make sure that 
no other device on your network is using that IP address.