There are some who would refer to optimized disk-based target devices that are optimized for as Purpose-Built Backup Appliances (PBBAs), but that term is actually misleading.
When one refers to a “backup server,” the implication is that the server performs backups—and in fact, those servers do perform backups.
When one refers to a “storage controller,” it is in reference to a device that controls storage.
In both examples, the first word is the activity performed by the second word.
Some in the industry have chosen to refer to the disk-based target devices covered in ESG’s recently published “Market Landscape Report on Disk-Based Backup Targets” as purpose-built (i.e. specifically architected) “backup appliances” — but most of those appliances don’t actually do backups; they enable backups. The consideration factors and representative solutions discussed in the report should more correctly be referred to as deduplication appliances or optimized‑retention appliances, because they are appliances that do deduplication and do deliver optimized retention.
To actually be a “purpose built” backup appliance (i.e. do backups), a solution would need to be self‑contained, including not only optimized-storage, but also backup server software for scheduling and management backups, such as an EMC Avamar, Axcient, Evault or Symantec 3600/5230.
In a future Market Landscape Report, it is likely that ESG will separately look at the market trends and the range of real purpose-built backup appliances – but in the meantime, enjoy the MLR on Disk-Based Target Systems, covering Dell, EMC, Exagrid, HP, NetApp, Quantum, and Sepaton.