IP+Address

=IP Address= Author: Valerie Liang

An IP Address, or Internet Protocol Address, is a series of 4 numbers assigned to each computer in a network so that they can communicate with each other. Every computer has their own unique IP address. Each number is a number from 0-255, and is separated by a dot. For example, a typical IP address might look like this: 174.34.172.246 (which is the IP address for www.daischina.org). While we use these digits from 0-255, the computer only knows binary form, which is two digits: 0 and 1. Therefore, it uses the binary form of the IP address, which is made up of four sets of eight 0's and 1's, each set called an octet. With four sets of octets, there are over 4.3 billion possible combinations for IP addresses.

There are two main functions of an IP Address. The first is to identify the computers or other devices that are connected to a running Internet Protocol. The second is to send and receive information to and from different computers. You need an IP address if you want to connect to the internet because it is a rule that every network must give its address to any other network it connects with, and also know every address of any network it connects with.

The octets are also used to classify IP addresses based on what business, organization or other entity they belong to, and how big their size is. **Class A** is used for major corporations, and its size is huge. Any IP address who has a number of 1 to 126 in its first octet is part of Class A. They make up half of all IP addresses. **Class B** is reserved for medium sized networks. The first octet has to have a number from 128 to 191, making up a fourth of all IP addresses. **Class C** IP addresses are used for smaller businesses. You can tell if an IP address is Class C if the number in the first octet is a number from 192 to 223. **Class D** is used only for multicasts, which is where everyone registered in a special group can receive a packet sent out by a node. They make up only a sixteenth of all addresses. **Class E** addresses are for experimental purposes, and is also only a sixteenth of all addresses. **Broadcast** IP addresses are used to send information to all computers on one network. They always have the IP address 255.255.255.255.