What is an IP address?
An Internet Protocol (IP) address
is a numerical identification (logical address
) that is assigned to devices participating in a computer network utilizing
the Internet Protocol for communication between its nodes. Although IP addresses are stored as binary numbers, they are usually displayed
in human-readable notations, such as 192.168.100.1 (for IPv4), and 2001:db8:0:1234:0:567:1:1 (for IPv6).
The role of the IP address has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."
Every device connected to the public Internet
is assigned a unique number known as an Internet Protocol (IP) address
IP addresses consist of four numbers separated by periods (also called a 'dotted-quad') and look something like 127.0.0.1.
Since these numbers are usually assigned to internet service providers within region-based blocks
, an IP address
can often be used to identify the region or country
from which a computer is connecting to the Internet.
An IP address can sometimes be used to show the user's general location
Because the numbers may be tedious to deal with, an IP address may also be assigned to a Host name,
which is sometimes easier to remember.
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 user to host websites
, mail servers
, ftp servers, etc.
In addition to users connecting to the internet, with virtual hosting
, a single machine can act like multiple machines (with multiple domain names and IP addresses