What does "data at rest" encryption protect?

"Data at rest" encryption specifically focuses on protecting data that is stored on devices, disks, or databases, which is crucial for ensuring the confidentiality and integrity of sensitive information when it is not actively being used or transmitted. This type of encryption is essential for preventing unauthorized access to data that might be stored on servers, external drives, or cloud storage services.

By encrypting data at rest, organizations can safeguard it against theft or breaches, particularly in scenarios where physical security measures may be lacking or fail. This ensures that even if an attacker gains access to the stored data, they will not be able to read or use it without the decryption keys.

In contrast, the other options focus on different states of data. For instance, data being transmitted over the internet refers to "data in transit," which requires separate encryption methods such as TLS (Transport Layer Security). Similarly, data being processed involves data actively used by applications, which is also not covered by data at rest encryption. Data shared in real-time applies to live communications, emphasizing temporal and contextual security measures different from those needed for stored data. Thus, the focus on stored data makes the chosen answer the most relevant to the question of what data at rest encryption protects.