An Internet Protocol address (IP address) is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing.
Internet Protocol version 4 (IPv4) defines an IP address as a 32-bit number. However, because of the growth of the Internet and the depletion of available IPv4 addresses, a new version of IP (IPv6), using 128 bits for the IP address, was developed in 1995, and standardized as RFC 2460 in 1998. IPv6 deployment has been ongoing since the mid-2000s.
IP addresses are usually written and displayed as 172.16.254.1 in IPv4, and 2001:db8:0:1234:0:567:8:1 in IPv6.
IP versions
Two versions of the Internet Protocol are in common use in the Internet today. The original version of the Internet Protocol for use in the Internet is Internet Protocol version 4 (IPv4), first deployed in 1983.
IPv6 technology was in various testing stages until the mid-2000s, when commercial production deployment commenced.
IPv4 addresses
An IPv4 address has a size of 32 bits, which limits the address space to 4294967296 (232) addresses. Of this number, some addresses are reserved for special purposes such as private networks (~18 million addresses) and multicast addressing (~270 million addresses).
IPv4 addresses are usually represented in dot-decimal notation, consisting of four decimal numbers, each ranging from 0 to 255, separated by dots, e.g., 182.193.244.301. Each part represents a group of 8 bits (an octet) of the address. In some cases of technical writing, IPv4 addresses may be presented in various hexadecimal, octal, or binary representations.
IPv6 addresses
In IPv6, the address size was increased from 32 bits in IPv4 to 128 bits or 16 octets, thus providing up to 2128 (approximately 3.403×1038) addresses. This is deemed sufficient for the foreseeable future. All modern desktop and enterprise server operating systems include native support for the IPv6 protocol, but it is not yet widely deployed in other devices, such as residential networking routers, voice over IP (VoIP) and multimedia equipment, and network peripherals.
IP address assignment
IP addresses are assigned to a host either dynamically at the time of booting, or permanently by fixed configuration of the host hardware or software. Persistent configuration is also known as using a static IP address. In contrast, when a computer’s IP address is assigned newly each time it restarts, this is known as using a dynamic IP address.
The configuration of a static IP address depends in detail on the software or hardware installed in the computer. Computers used for the network infrastructure, such as routers and mail servers, are typically configured with static addressing, Static addresses are also sometimes convenient for locating servers inside an enterprise.
Some Extra Points
127.0.0.1 Is A Local Host IP Address. We can access this IP by enabling the IIS Service from the Windows Control panel Or By Installing Some Third Party Applications. (Like : Xampp Or Wamp Server).
192.168.xxxx.xxxx is a Local IP Of Any Computer. It Is Changing In Every Computer But the Prefix 192.168 is Same in every computer.
We can Run Offline Sites By Using The 127.0.0.1 IP on our PC. We can also add some new IP’s Like 127.0.0.2, 127.0.0.69, 127.0.xxxx.xxxx etc… and all the IP’s With 127.0.x.x are only run on Offline Mode.
| CLASS | ADDRESS RANGE | SUPPORTS |
| Class A | 1.0.0.1 to
126.255.255.254 |
Supports 16 million hosts on each of 127 networks. |
| Class B | 128.1.0.1 to
191.255.255.254 |
Supports 65,000 hosts on each of 16,000 networks. |
| Class C | 192.0.1.1 to
223.255.254.254 |
Supports 254 hosts on each of 2 million networks. |
| Class D | 224.0.0.0 to
239.255.255.255 |
Reserved for multicast groups. |
| Class E | 240.0.0.0 to
254.255.255.254 |
Reserved for future use, or Research and Development Purposes. |