The strongest variant of the AES encryption standard, using a 256-bit key length to protect highly sensitive data at rest and in transit.
- AES-256 is the gold standard for database encryption: It is required by many government, defense, and financial compliance frameworks.
- SQL Server supports AES-256 for: TDE, backup encryption, and Always Encrypted — providing the highest available protection level.
- Compared to AES-128: AES-256 offers greater key space but with marginally higher computational cost — negligible on modern hardware.
- Recommended for databases storing: PII, PHI, financial records, or any data classified as highly confidential.
- SQL Secure by Idera: Can audit whether AES-256 encryption is enforced consistently across all databases and backups in your environment.
- Related terms: AES-128, Transparent Data Encryption (TDE), Always Encrypted, column-level encryption.
