Encryption at Rest: Protecting Stored Data

Encryption at Rest: Protecting Stored Data

Encryption at rest protects data stored on disk from unauthorized access, whether through physical theft, improper disposal, or system compromise. Full disk encryption provides broad protection but may not prevent access from applications or users with system access. Database-level encryption offers more granular control, allowing different encryption keys for different data categories, though it requires careful integration with application logic.

Transparent Data Encryption (TDE) available in enterprise databases automates encryption at the storage layer, requiring minimal application changes. However, TDE doesn't protect against database-level attacks since data appears decrypted to authenticated database connections. Column-level encryption provides finer control, encrypting specific sensitive fields while leaving others accessible for indexing and querying. This approach requires application-level key management and can complicate database operations.

Application-level encryption offers maximum control over encryption operations, allowing developers to implement custom schemes tailored to specific requirements. This approach enables features like client-side encryption, where data is encrypted before reaching servers, providing protection even against compromised infrastructure. However, application-level encryption increases complexity and requires robust key management solutions to prevent keys from being exposed in code or configuration files.