Storage Encryption (SE) supports SEDs that encrypt data as it is written. The data cannot be read without an encryption key stored on the disk. The encryption key, in turn, is accessible only to an authenticated node.

On an I/O request, a node authenticates itself to an SED using an authentication key retrieved from an external key management server or Onboard Key Manager:

SE supports self-encrypting HDDs and SSDs. You can use Volume Encryption with SE to double encrypt data on SE drives.

NVMe SEDs do not have FIPS 140-2 certification, however, these disks use AES 256-bit transparent disk encryption to protect data at rest.

Data encryption operations, such as generating an authentication key, are performed internally. The authentication key is generated the first time the disk is accessed by the storage system. After that, the disks protect data at rest by requiring storage system authentication each time data operations are requested.

Aggregate Encryption (AE) is a software-based technology for encrypting all data on an aggregate. A benefit of AE is that volumes are included in aggregate level deduplication, whereas VE volumes are excluded.

With AE enabled, the volumes within the aggregate can be encrypted with aggregate keys.

Beginning with ONTAP 9.7, newly created aggregates and volumes are encrypted by default when you have the VE license and onboard or external key management.

Volume Encryption is a software-based technology for encrypting data at rest one volume at a time. An encryption key accessible only to the storage system ensures that volume data cannot be read if the underlying device is separated from the system.

Both data, including Snapshot copies, and metadata are encrypted. Access to the data is given by a unique XTS-AES-256 key, one per volume. A built-in Onboard Key Manager secures the keys on the same system with your data.

You can use VE on any type of aggregate (HDD, SSD, hybrid, array LUN), with any RAID type, and in any supported ONTAP implementation. You can also use VE with Storage Encryption (SE) to double encrypt data on SE drives.