Ip Address And Subnet Mask; Private Ip Addresses; Table 7-1 Example Of Network Properties For Lan Servers With Fixed Ip Addresses - ZyXEL Communications ZyXEL ZyWALL 2WE User Manual

There are two ways that an ISP disseminates the DNS server addresses.
The first is for an ISP to tell a customer 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
DHCP Setup.
The second is to leave this field blank, i.e., 0.0.0.0 — in this case; the ZyWALL acts as a DNS proxy.

Table 7-1 Example Of Network Properties For LAN Servers With Fixed IP Addresses

Choose an IP address
Subnet mask
Gateway (or default route)
7.4.3

IP Address and Subnet Mask

Similar to the way houses on a street share a common street name, so too do machines 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 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
three 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, for
example192.168.1.1, for your ZyWALL, 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 ZyWALL 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 ZyWALL unless you are instructed to do otherwise.

Private IP Addresses

Every computer on the Internet must have a unique IP 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:
LAN Setup
192.168.1.2 - 192.168.1.32; 192.168.1.65 - 192.168.1.254
255.255.255.0
192.168.1.1 (ZyWALL LAN IP Address)
ZyWALL 2 and ZyWALL 2WE
7-3