Which of the following is the identification of hosts using four octets separated by periods?

The identification of hosts using four octets separated by periods is known as IPv4 addressing. An IPv4 address consists of four decimal numbers (ranging from 0 to 255) that are separated by periods, for example, 192.168.1.1. This format allows for a total of approximately 4.3 billion unique addresses, although the actual number available for public use is less due to various factors like reserved addresses and network configurations.

In contrast, IPv6 addressing utilizes a different format that employs hexadecimal numbers and is displayed as eight groups of four hexadecimal digits, separated by colons. MAC addressing identifies devices on a local network using a unique identifier assigned to network interfaces, presented in a format consisting of six groups of two hexadecimal digits. URL addressing refers to the structure of web addresses but does not specifically describe a method for identifying hosts in the same way as IP addressing does. Hence, the correct identification specifying four octets separated by periods is accurately defined by IPv4 addressing.