ZyXEL GS-105I User Guide - Page 136

Private IP Addresses

Page 136 highlights

Chapter 8 Home Networking 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 do not need to change the subnet mask computed by the Zyxel Device unless you are instructed to do otherwise. 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 • 172.16.0.0 - 172.31.255.255 • 192.168.0.0 - 192.168.255.255 You can obtain your IP address from the IANA, from an ISP or it can be assigned from a private network. If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you with the Internet addresses for your local networks. On the other hand, if you are part of a much larger organization, you should consult your network administrator for the appropriate IP addresses. Note: Regardless of your particular situation, do not create an arbitrary IP address; always follow the guidelines above. For more information on address assignment, please refer to RFC 1597, "Address Allocation for Private Internets" and RFC 1466, "Guidelines for Management of IP Address Space". PX7511-B0 User's Guide 136

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Chapter 8 Home Networking
PX7511-B0 User’s Guide
136
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 do not need to change
the subnet mask computed by the Zyxel Device unless you are instructed to do otherwise.
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
• 172.16.0.0
— 172.31.255.255
192.168.0.0 — 192.168.255.255
You can obtain your IP address from the IANA, from an ISP or it can be assigned from a private network.
If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you
with the Internet addresses for your local networks. On the other hand, if you are part of a much larger
organization, you should consult your network administrator for the appropriate IP addresses.
Note: Regardless of your particular situation, do not create an arbitrary IP address; always
follow the guidelines above. For more information on address assignment, please refer
to RFC 1597, “Address Allocation for Private Internets”
and RFC 1466, “Guidelines for
Management of IP Address Space”.