Quantum Adds De-Dupe To VTL Line

Data de-duplication, also called data de-dupe, removes duplicate information as data is backed up or archived. It can be done on the file level, where duplicate files are replaced with a marker pointing to one copy of the file, or at the sub-file level, or byte level, where duplicate bytes of data are removed, resulting in a decrease in storage capacity requirements of several magnitudes.

Virtual tape libraries, or VTLs, are disk arrays configured to look to the host server and the backup software as if they are physical tape libraries. Data is streamed to and recovered from the VTL as if it were tape, so no changes are needed to the backup process. However, because they use hard drives, the backup and recover speed is much higher than when using tape drives. Data backed up to a VTL can also be backed up to a physical tape for archiving or off-site storage.

Quantum's new DXi family is based on the DX family of virtual tape libraries the company previously has been selling, said Shane Jackson, director of enterprise product marketing for the San Jose, Calif.-based storage vendor.

Also included is the embedded file system from ADIC, which Quantum acquired in May.

The heart of the DXi family, however, comes from the de-dupe technology ADIC acquired when it purchased Rocksoft in March. Using the de-dupe capability can compress data from between 10:1 and 50:1, with speeds of up to 800 Gbytes per hour, which Jackson said is about twice that of Quantum's main competitor, Data Domain, Santa Clara, Calif.

However, Jackson said, Quantum does not really emphasize the compression ratio. "We're not focused on the ratio, but on how much data customers need to protect," he said. "We look at what customers need to protect for the next three to four months."

De-dupe for virtual tape libraries allows customers to cut the amount of storage capacity required for backups, and allow easy replication of data from one virtual tape library to another.

There are a total of eight models in the DXi family. The DXi3500 can be configured in four different models to protect from 1.2 Tbytes to 4.2 Tbytes of primary data at up to 290 Gbytes per hour, while the DXi5500 can be configured in one of four models to protect from 3.6 Tbytes to 10.8 Tbytes at up to 800 Gbytes per hour.

John Zammett, president of HorizonTek, a Huntington, N.Y.-based solution provider, said his company has gotten a lot of requests from customers for de-dupe technology, and is glad to see Quantum release its DXi family.

"We've already got customers lined up for it," Zammett said. "It's what they've been waiting for. And it's very price-competitive."

The DXi family is scheduled to start shipping next month. List price starts at about $24,000 for the DXi3500 with enough capacity to protect up to 1.5 Tbytes for two to three months, which Jackson said is equivalent to about 24 Tbytes of total primary storage capacity.

Optional licenses for connection to Fibre Channel networks and for replication from one VTL to another will also be available soon, with pricing to be determined.