ZyXEL N4100 Guia Do Utilizador

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N4100 User’s Guide
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P P E N D I X
   
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IP Addresses and Subnetting
This appendix introduces IP addresses and subnet masks. 
IP addresses identify individual devices on a network. Every networking device 
(including computers, servers, routers, printers, etc.) needs an IP address to 
communicate across the network. These networking devices are also known as 
hosts.
Subnet masks determine the maximum number of possible hosts on a network. 
You can also use subnet masks to divide one network into multiple sub-networks.
Introduction to IP Addresses
One part of the IP address is the network number, and the other part is the host 
ID. In the same way that houses on a street share a common street name, the 
hosts on a network share a common network number. Similarly, as each house 
has its own house number, each host on the network has its own unique 
identifying number - the host ID. Routers use the network number to send packets 
to the correct network, while the host ID determines to which host on the network 
the packets are delivered.
Structure
An IP address is made up of four parts, written in dotted decimal notation (for 
example, 192.168.1.1). Each of these four parts is known as an octet. An octet is 
an eight-digit binary number (for example 11000000, which is 192 in decimal 
notation). 
Therefore, each octet has a possible range of 00000000 to 11111111 in binary, or 
0 to 255 in decimal.