What is an IP address

Every machine on the Internet has a unique identifying number, called an IP Address. A typical IP address look like this: 195.24.53.107


The four numbers in an IP address are used in different ways to identify a particular network. Those numbers are called octets, because they each have eight positions when viewed in binay form. The octets serve a purpose other than simply separating the numbers. They are used to create classes of IP addresses.

* Class A- This class is for very large networks, such as a major international company might have. IP addresses with a first octet from 1 to 126 are part of this class.

* B- Class B is used for medium-sized
networks. A good example is a large college campus. IP addresses with a first octet from 128 to 191 are part of this class.


* Class C- Class C addresses are commonly used for small to mid-size business. IP addresses with a first octet from 192 to 223 are part of this class.

* Class D- Used for multicasts (where a node sends a packet addressed to a special group address.). For multicasts, the first octet has a value of 224.

* Class E with the first octet of 225 is used for experimental purposes only.

Loopback- The IP address 127.0.0.1is used as the loopback address. This means that it is used by the host computer to send a message back to itself. It is commonly used for troubleshooting and network testing.

Broadcast- Messages that are intended for all computers on a network are sent as broadcasts. These messages always use the IP address
255.255.255.255.

source: www.selfseo.com