Encryption at Rest Explained

Protect stored data from unauthorized access — encrypting databases, files, and backups so they cannot be read without proper decryption keys.

Encryption at Rest

Encryption at rest protects stored data by encrypting it on disk so that it cannot be read without the proper decryption keys, even if the physical storage media is accessed or stolen.

Explanation

Data at rest includes databases, file systems, backups, and any persistent storage. Encryption at rest uses symmetric encryption algorithms (AES-256 is the standard) to encrypt data before writing it to disk and decrypt it when authorized applications read it. Key management is critical: keys must be stored separately from data, rotated regularly, and access-controlled. Cloud providers offer transparent encryption at rest (AWS KMS, Azure Key Vault, GCP Cloud KMS) that handles encryption and key management automatically. Regulations like GDPR, HIPAA, and SOC 2 often require encryption at rest for sensitive data.

Bookuvai Implementation

Bookuvai enables encryption at rest for all production databases and storage. We use cloud-provider KMS for key management, configure automatic key rotation, and ensure backups are encrypted with the same standards as primary data. All sensitive fields receive application-level encryption in addition to storage-level encryption.

Key Facts

  • Protects stored data from unauthorized access even if storage is compromised
  • AES-256 is the industry standard encryption algorithm
  • Key management: store keys separately, rotate regularly, control access
  • Cloud KMS services automate encryption and key management
  • Required by GDPR, HIPAA, SOC 2, and PCI DSS compliance frameworks

Related Terms

Frequently Asked Questions

Does encryption at rest affect performance?
Modern hardware acceleration (AES-NI instructions) makes encryption at rest nearly transparent. Cloud-managed encryption adds less than 5% overhead. The performance impact is negligible compared to the security benefit.
Is cloud-provider encryption sufficient?
Cloud-provider encryption at rest protects against physical theft and unauthorized disk access. For sensitive data like PII or payment information, add application-level encryption so data remains encrypted even if the database is compromised.
What is key rotation?
Key rotation periodically replaces encryption keys with new ones. If a key is compromised, only data encrypted with that key is at risk. Cloud KMS services automate rotation and re-encrypt data transparently.