IP Addressing and Subnetting workbooks, an IP address is an address used to uniquely identify a device in an IP network. The address consists of 32 binary bits, which can be divisible into a network portion and a host portion with the help of a subnet mask.
The 32 binary bits are divided into four octets (1 octet = 8 bits). Each octet is converted to a decimal and separated by a period (period). For this reason, it is said that an IP address is expressed in dotted decimal format (for example, 172.16.81.100). The value in each octet varies from 0 to 255 decimal, or 00000000 – 11111111 binary.