Removable disk cartridges aimed at tape

By Kevin Komiega

Disk-based backup has quickly found its way into the storage plans of many organizations, but tape lives on for many reasons: It’s removable and inexpensive and has a shelf life that meets long-term archival requirements. But if you could take those attributes and apply them to disk, would you eliminate tape from the backup process altogether? ProStor Systems is betting you would.

This month, the storage start-up came out of stealth mode to announce an archival disk cartridge that boasts all of the performance benefits of disk and the portability and archival features of tape.

The new product, called the RDX Archival Disk Cartridge, is a 2.5-inch removable Serial ATA (SATA) hard drive that looks and acts like a tape cartridge, but performs with the speed and reliability of disk.

According to ProStor Systems’ president and CEO Steve Georgis, RDX offers the best of both worlds. “We retained the advantages of tape and combined them with the advantages of disk while overcoming the reliability and performance issues of tape.”

ProStor has not officially announced a product road map beyond its first product launch planned for early 2006. The company is currently prepping 60GB and 120GB cartridges with data-transfer rates that are “on par” with those of LTO tape technology at 30GBps. ProStor expects to refresh its cartridge capacities and speeds every nine months as new drives are released from suppliers. (The company’s technology reportedly works with any manufacturer’s SATA drives.)

ProStor claims that it can overcome the technical limitations that have historically relegated disk to a shorter life than tape. Disk drives are normally formatted into sectors, each with a basic level of error-correction capabilities. Disks tend to be sensitive to magnetic thermal decay and defects that overwhelm their ability to correct errors. However, ProStor adds a second level of data correction that is capable of correcting multiple, full sectors of a disk which, according to Georgis, can extend the life of its disk cartridges to two decades.

“We can correct almost all errors and maintain ‘five nines’ of data reliability over 20 years,” Georgis claims.

The RDX drive and cartridge systems will also feature built-in AES encryption and interoperability with existing backup hardware and software applications.

Robert Amatruda, research manager for tape and removable storage at International Data Corp., believes ProStor has figured out the technical challenges of removable disk to make it a viable replacement for tape in certain organizations, but where the technology might experience some resistance is within the OEM community.

“ProStor has built in the algorithms and firmware to make a drive tape-like and suitable for a long life,” says Amatruda, “but all of the vendors that make or re-brand tape make quite a bit of margin on hardware and media. That creates a very strong underpinning for tape. ProStor is going to have to figure out how to break that cycle.”

ProStor’s removable disk cartridges will initially attack tape’s hold on the entry-level market, according to Amatruda. He believes the technology will find a role in local backup for workstations and in distributed environments for small and medium-sized businesses (SMBs), with the potential to move upstream into larger enterprises.

“At the very low-end, RDX is really meant to replace tape and not to play alongside it. If ProStor goes up market there is potential to run side-by-side with tape,” says Amatruda.

Official pricing has not been announced, but Georgis says the cartridges will break the dollar-per-gigabyte threshold, with the ultimate objective of costing less than tape.

ProStor has made evaluation units of its cartridges available to OEMs for testing and is in the process of placing units at beta test sites.

This article was originally published on November 01, 2005