An IP Address is 4 sets of decimal numbers,
0-255, separated by periods (for example, 192.168.255.251) which form the address of
a computer on the internet or within a local network, and allow it to
be referenced by other computers.
An IP address consists of two parts, a network
portion and a host portion.
Within a single network, for
example the one you are about to set up, all computers will have
identical network portions. In order for two computers to communicate with each
other directly, they must be in the same network, and thus have identical network
portions of their IP addresses.
The host portion of an IP address
indicates a computer's unique identifier within its network. Every computer on a
given network must have a unique host portion in order to communicate with other
computers in the same network.
An IP address is
always accompanied by a subnet mask, which separates the network and host portions of
the IP address. A subnet mask is shown in the same format
as the IP address (for example 255.255.255.0). As far as this article
is concerned, assume that the values of the 4 sets of numbers in the subnet mask
can be either 0 or 255.
Sets with the value of 0 indicate the
host portion of the IP address, and sets with the value of 255 indicate
the network portion. For example, with an IP address of 192.168.3.25 and
a subnet mask of 255.255.255.0, the network portion of the address would
be '192.168.3', and the host portion would be '.25'. This means the computer assigned this address
is host 25 within the 192.168.3 network.
get significantly more complex than this, especially when you consider that the
subnet mask is not actually restricted only to values of 0 or 255, but that is
beyond the scope of this article.
Now, on with the networking!