Tape Technology Stretches Out

Computerworld - Like many IT executives, Eric Eriksen, chief technology officer at New York-based Deloitte Consulting, would like tape to just go away. The added cost of managing tape backup systems, slow and unreliable restoration, cartridge inventorying and off-site storage headaches have him hoping that cheap disk drives may someday replace 50-year-old tape technology in the data center.

"We only need tape for cases when we can't restore from disk. It's a necessary evil," he says.

Yet despite a drastic shift toward low-cost Advanced Technology Attachment disk arrays for backing up business data, there's no end in site to the use of tape in the data center — especially for archival storage. Administrators may complain, but tape still has an enormous installed base and remains 10 to 50 times less expensive than disk. It's also very secure, since data stored off-line on removable media is physically inaccessible to hackers and viruses.

And vendors and analysts say evolutionary advances in the basic technology in midrange tape drive systems, improvements in management tools, and the emergence of combined disk/tape subsystems are likely to answer some user complaints — and keep tape technology in data centers for at least another decade.

Bigger and Faster

Manufacturers of the three leading midrange tape drive technologies — digital linear tape (DLT), linear tape-open (LTO) and advanced intelligent tape (AIT) — are preparing significant capacity and speed improvements. Advanced drives, including SuperDLT (SDLT), SuperAIT (S-AIT) and LTO Ultrium 2 (LTO-2), are the latest variations. Each uses half-inch tape and offers roughly five times the capacity and performance of standard DLT, AIT and LTO tapes [For a more detailed explanation of these technologies, go to QuickLink 40422].

For example, DLT was developed in 1986 and the average cartridge originally held about 96MB of data. SDLT today holds 160GB. Over the next decade, SDLT will grow to about 2.5TB native capacity with 250MB/sec. throughput. LTO, which derives its name from its open architecture, could grow to 10TB native capacity by 2011.

Vendors say 1TB tape cartridges could appear as early as next year. Tape manufacturers such as Quantum Corp., Certance LLC and Storage Technology Corp. expect tape to more than meet future needs. That's a tall order, since the amount of data produced by the average enterprise is doubling every year, according to Stamford, Conn.-based Gartner Inc.

To keep up, tape media will evolve to have more than 1,000 tracks and a thickness of 6.9 microns (about as thick as cellophane). And it will also work with drives that write on both sides of the tape, says Jeff Laughlin, director of strategy for the automated tape solutions unit at StorageTek in Louisville, Colo.