2 November 2012

What is an IP (Internet Protocol) address and types of IP?


What is an IP (Internet Protocol) address?
Every device connected to the public Internet is assigned a unique number known as an IP address. IP addresses consist of four numbers separated by periods (also called “dotted-quad”).
These numbers are usually assigned to internet service providers within region based blocks, an IP address can often helpful to identify the region or country from which the computer is connecting to the network. An IP address can used to show the Internet user general location.
Since an IP address may also be assigned to a Host name, which is sometimes easier to remember. Host names may be looked up to find IP addresses, and vice-versa. At one time ISPs issued one IP address to each user. These are called static IP addresses. Because there is a limited number of IP addresses and with increased usage of the internet ISPs now issue IP addresses in a dynamic fashion out of a pool of IP addresses (Using DHCP). These are referred to as dynamic IP addresses. This also limits the ability of the users to host websites, mail, ftp servers, etc. In addition to users connecting to the internet, with virtual hosting, a single machine can act like multiple machines.
Types of IP address

The designers of the Internet Protocol defined an IP address as a 32-bit number and this system, known as Internet Protocol Version, is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new version [of IPv6], using 128 bits for the address, was developed in 1995.
IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations.
Example:             IPv4:      158.16.234.1 
   IPv6:      2002:db8:0:1234:0:567:8:9