ZyXEL 793H Guida Utente

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 Chapter 6 LAN Setup
P-793H User’s Guide
95
• 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.
• The ZyXEL Device acts as a DNS proxy when the Primary and Secondary DNS Server 
fields are left as 0.0.0.0 in the DHCP Setup screen.
6.2  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.
The LAN parameters of the ZyXEL Device are preset in the factory with the following values:
• IP address of 192.168.1.1 with subnet mask of 255.255.255.0 (24 bits)
• DHCP server enabled with 32 client IP addresses starting from 192.168.1.33. 
These parameters should work for the majority of installations. If your ISP gives you explicit 
DNS server address(es), read the embedded web configurator help regarding what fields need 
to be configured.
6.2.1  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.
The subnet mask specifies the network number portion of an IP address. Your ZyXEL Device 
will compute the subnet mask automatically based on the IP address that you entered. You 
don't need to change the subnet mask computed by the ZyXEL Device unless you are 
instructed to do otherwise.