ZyXEL Communications P-2900-4HB User Manual

Chapter 5 LAN Setup

P-2900-4HB User’s Guide

This section provides some technical background information about the topics 
covered in this chapter.

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 the DHCP server off, you must have another DHCP server on your LAN, or 
else the computer must be manually configured. 

The ZyXEL Device is pre-configured with a pool of IP addresses for the DHCP 
clients (DHCP Pool). See the product specifications in the appendices. Do not 
assign static IP addresses from the DHCP pool to your LAN computers.

There are two ways that an ISP disseminates the DNS server addresses. 

• 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 the DNS server 

addresses, enter them in the DNS Server fields in the LAN Setup screen.

• The ZyXEL Device acts as a DNS proxy when the Primary and Secondary DNS 

Server fields are left blank in the LAN Setup screen.

The ZyXEL Device has built-in DHCP server capability that assigns IP addresses 
and DNS servers to systems that support DHCP client capability.

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