A storage infrastructure that is managed by software as opposed to by the storage hardware. In essence, the software level is decoupled from the physical hardware. The software is policy-based and provides storage functionalities such as deduplication, thin provisioning, replication, snapshots.
There are a number of benefits to the SDS approach:
Organizations are not locked in to individual vendor's proprietary storage systems. In addition, storage administrators can provision storage without worrying about the underlying hardware attributes.
SDS provides a central point of access to all storage management functions, which makes life easier for storage administrators.
Compared to traditional storage systems, which requires many labor-intensive provisioning steps, SDS allows organizations to provision new storage quickly.
Commodity hardware can be used for storage as opposed to specialized hardware, which not only costs more to purchase but often require an annual maintenance fee. Therefore an organization can save on both CapEx and OpEx.
There are several challenges that have been discussed:
It may be difficult to provision traditional hardwired storage dynamically.
Security needs to be applied across the whole storage environment
With SDS, the system administrators need to make sure all the storage systems function well with one another, as components come from different vendors. On the other hand, a traditional storage appliance comes in a more turnkey fashion - a single vendor would be responsible for an entire piece of hardware. So, setup and getting support may be more time-consuming.