The Internet Protocol

Module 8.

Purpose of IPv4 Addressing

IPv4 address is a logical network address to identify a particular host. The address is assigned to the network interface connection for a host, this is normally a Network Interface Card (NIC). Every packet sent across the internet has a source and destination IPv4 address.

IPv4 address are 32 bits in length. An IPv4 address in binary format would appear like so: 11010001101001011100100000000001. This is very hard to read, and so, the 32 bits are grouped into 8-bit bytes (octets) like this: 11010001.10100101.11001000.00000001. This can then be converted into dotted decimal representation: 209.165.200.1.

IPv4 Address Structure

Logical IPv4 addresses are hierarchical and made up of two parts; network and host. The network portion of address 192.168.5.11 is 192.168.5 and the host portion is the .11. Routers only need to know the network portion of the address in order to send packets to the correct hosts.