Storage Server
- High Storage Density (up to 24 Hot-Swap SATA HDDs in 4U)

- Redundant Power Supply

- Ideal for SAN, NAS, Cloud, or iSCSI Applications

Disk Expansion Enclosure
JBOD (Just a Bunch of Disks) is an array of hard disks that are merely concatenated together and haven't been configured as a redundant mechanism.
External Disk Array
External disk array is designed to provide systems with the ability to consolidate and share data at an affordable price, while leveraging advanced software capabilities usually found in more expensive mid-range & high-end systems.