Chapter 3 Internet Access; Tcp/Ip And Dhcp For Lan; Factory Lan Defaults; Ip Address And Subnet Mask - ZyXEL Communications ZyWALL 10 User Manual

This chapter shows you how to configure the LAN as well as the WAN of your ZyWALL for Internet
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TCP/IP and DHCP for LAN

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

3.1.1 Factory LAN Defaults

The LAN parameters of the ZyWALL are preset in the factory with the following values:
1. IP address of 192.168.1.1 with subnet mask of 255.255.255.0 (24 bits)
2. DHCP server enabled with 32 client IP addresses starting from 192.168.1.33.
These parameters should work for the majority of installations. If the parameters are satisfactory, you can
skip to section 3.2 to enter the DNS server address(es) if your ISP gives you explicit DNS server address(es).
If you wish to change the factory defaults or to learn more about TCP/IP, please read on.

3.1.2 IP Address and Subnet Mask

Similar to the houses on a street that share a common street name, the machines on a LAN share one
common network number, also.
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 feature of the ZyWALL. 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 3 numbers
specify the network number while the last number identifies an individual workstation on that network.
Once you have decided on the network number, pick an IP address that is easy to remember, e.g.,
192.168.1.1, for your ZyWALL, but make sure that no other device on your network is using that IP.
Internet Access
ZyWALL 10 Internet Security Gateway
Chapter 3
Internet Access
access.
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