Which protocol uses a numerical address structure known as octets?

The protocol that utilizes a numerical address structure known as octets is IPv4. In IPv4 addressing, an address is composed of four octets, each consisting of 8 bits, separated by periods. This structure allows for over four billion unique addresses, represented in a format like 192.168.1.1.

Each octet in an IPv4 address can range from 0 to 255, since it's represented in decimal notation. This organization reflects the underlying binary nature of digital communication, where each octet corresponds to a byte of data.

Understanding octets is crucial for networking professionals, as it helps in diagnosing network issues, configuring network devices, and understanding IP address allocation. In contrast, IPv6 uses a hexadecimal representation, IPSec is a framework for securing Internet Protocol communications, and DHCP is a protocol for dynamically assigning IP addresses to devices on a network. These do not utilize the same octet structure as IPv4.