ZyXEL Communications P-873HNU-51B, Руководство пользователя

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Chapter 8 Home Networking
P-873HNU(P)-51B User’s Guide
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The subnet mask specifies the network number portion of an IP address. Your VDSL Router 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 VDSL Router 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”.