ZyXEL P-663H-51 Guia Do Utilizador

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Chapter 6 LAN Setup
P-663H-51 User’s Guide
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6.1.2  DHCP Setup
DHCP (Dynamic Host Configuration Protocol, RFC 2131 and RFC 2132) allows individual 
clients to obtain TCP/IP configuration at start-up from a server. You can configure the ZyXEL 
Device as a DHCP server or disable it. When configured as a server, the ZyXEL Device 
provides the TCP/IP configuration for the clients. If you turn DHCP service off, you must 
have another DHCP server on your LAN, or else the computer must be manually configured. 
Do not assign static IP addresses from the DHCP pool to your LAN computers.
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.
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.
6.2.1.1  Private IP Addresses
Every machine on the Internet must have a unique address. If your networks are isolated from 
the Internet, for example, only between your two branch offices, you can assign any IP 
addresses to the hosts without problems. However, the Internet Assigned Numbers Authority 
(IANA) has reserved the following three blocks of IP addresses specifically for private 
networks:
• 10.0.0.0     — 10.255.255.255