IP is the short form for Internet Protocol. It is an address of a computer. The addresses are divided into five categories. These categories are A, B, C, D and E respectively. Among these five categories, former three are in common use. Different ranges are used for IP Addresses. Some IP Addresses are automatically given to a computer when a home computer gets connected to other computers on the Internet.

Size of the network can be assumed through an IP address of a computer. These IP addresses help in getting the ID of a network and also the ID of host computer. Previously a lot depended upon the IP addresses, but now things have undergone a change, any IP address can be mapped up with any network.

Specialty of Class A Ip Address is that it belongs to a network with maximum hosts. There are hundred and twenty six networks which come under this category. First Octet is used up for network ID. This has a fixed bit at the beginning, and the bit is always a zero. The following seven bits are all ones. The twenty four bits in the octets stand for hosts ID. This allows for 126 networks and seventeen million hosts in each network. Number values in this set up of network starts with the numeric number 1; the end of this number is taken to be 127.

Class A is supposed to carry large addresses, followed by class B, and class C is supposed to have the smallest number of addresses, but in numbers these are maximum in existence.

One can trace the location of a computer from its IP address. Devices which are connected via public internet connections get a number, which is the IP address. The addresses have four numbers which in turn are separated by dots. These numbers are given to companies which provide internet services. A person from another country can be traced back to his general location via the IP address of his computer. To trace email senders, criminals etc., these IP addresses are a great help.

Address belonging to Class A Ip Address can be a special address. The addresses like these are reserved for special purpose, and they are used for special purpose. In Class A, 127.0.0.0 is used for only one single address. It is also called a loopback address. Special work assigned to this address is of testing the functional capacity of local network device.