What is the most commonly used method for disk encryption?

Encryption software is the most commonly used method for disk encryption because it offers a flexible and relatively easy way to protect data on storage devices. This software allows users to encrypt entire drives or specific files, using various encryption algorithms and methodologies. It provides a software-based solution that can be deployed across different types of systems, making it accessible for individual users and organizations alike.

Additionally, encryption software often comes with user-friendly interfaces, allowing for easier implementation and management of encryption keys. It is capable of operating on existing hardware without the need for specialized equipment, which makes it widely applicable in various scenarios, from personal laptops to enterprise-level systems.

While hardware-based encryption offers certain advantages, such as performance enhancements and protection even when the operating system is not running, it is generally less prevalent due to higher costs and the need for compatible hardware. Physical security measures and network-based security protocols are also important components of an overall security strategy, but they do not directly apply to disk encryption in the same way that encryption software does.