.NET Architecture & System Design Interview Question #158

What is encryption at rest?

Security Architecture, Multi-Tenancy & Disaster Recovery Senior Advanced

Quick Interview Answer

Encryption at rest protects stored data when it resides on disks, database files, backups, object storage, or other persistent media.

Detailed Explanation

Encryption at rest protects stored data when it resides on disks, database files, backups, object storage, or other persistent media.

It reduces exposure if storage media or snapshots are accessed improperly, but it does not replace application authorization. Key management, backup encryption, rotation, and access to decryption keys are part of the overall design.

Code Example

Application
   |
Database
[encrypted storage]

Keys are managed separately
with controlled access.