Internal Protocol

An IP (Internet Protocol) address is an address that is assigned to a piece of hardware which is connected in a newtwork to communicate with eachother. Each IP address is unique for every device (phones, tablets, computers, modems etc).

There are 2 versions of IP. 1) IPv4 2)IPv6


It is an older version of protocol. It uses 32-bit binary number to produce single unique address. E.g. As the maximum value of a 32-bit number is 232= 4,294,967,296. So it can produce upto 4.3 billion unique addresses.


Class Range Supports
Class A to 16 million hosts on each of 127 networks.
Class B to 65,000 hosts on each of 16,000 networks.
Class C to 254 hosts on each of 2 million networks.
Class D to Reserved for multicasting.
Class E to Reserved for future purpose (Research and development).

Ranges 127.x.x.x are reserved for the loopback or localhost.A loopback address is nothing but a special IP address ranges to and it doesn't require a physical connection to a network. Range broadcasts to all hosts in local network.


It is replacement of IPv4. As IPv4 exceeded its limit, IPv6 originated as a solution. It uses 128-bit binary number to produce single unique address. It uses 8 sets of hexadecimal (base-16) number to produce unique address. Each set is separated by colon. E.g. 2020:dcba:0000:0000:0000:0000:1010:9876 (can be written as 2020:dcba::1010:9876).

# Key Points

  • IP address can be divided into "network prefix and "host suffix".
  • Each IP packet must contain source and destination address.
  • Class C IP address is used for multicasting.
  • IP 127.x.x.x range is also called as loopback or localhost.