Why Tape Remains Relevant

Cost savings & other benefits keep tape viable

Like many companies, it's possible yours takes advantage of tried and true tape storage for data backup and archival purposes. According to a 2012 memo from representatives of numerous leading tape providers, however, tape's role is "dramatically expanding," including in the areas of big data, cloud computing, and high­performance computing. "Explosive data growth and shrinking IT bud­gets are putting pressure on com­panies to find innovative storage solutions to meet their organiza­tional demands," the memo reads. "Increasingly that means tape, thanks to its significant cost advantages, reli­ability, and continued innovations improving tape's capacity, speed, and ease-of-use." The following explores why tape remains relevant today and how companies are using tape.

The evolution of tape

Tape has come a long ways since its beginning. Released in 1952, the first magnetic tape drive for storing com­puter generated data was a 935 pound device that stored a mere 2.3MB of data. Further, fewer than 20 compa­nies and organizations were using tape storage that year. Today, tape capaci­ties hit 4TB (roughly 2 million times the 1952 capacity) on cartridges some 900 pounds lighter. Although count­less companies use tape now, due to advantages that disk-based storage of­fers over tape (including speed), some pundits predict tape's time is running out. But is this really the case?

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"There certainly is a lot of pop­ular mythology about tape being archaic or dead," says Mike Kahn, The Clipper Group (www.clipper.com) managing director. "Simply put, tape is alive and well and cost beneficial for many uses, mostly in archiving." Although tape is also used for backup, its main use now and ahead is storing valuable data for long du­rations, he says. Whereas backup is about backing up data and files as a precautionary measure, he says, archiving entails saving data "for a long time and usually at the lowest pos­sible cost per item or per megabyte." Tape remains relevant because it costs significantly less per unit of storage than other storage types while of­fering "reasonable performance for all but the most time-sensitive retrieval requirements," Kahn says.

Mike Karp, Ptak, Noel and Asso­ciates (www.ptaknoel.com) vice president, believes tape has lost some relevance due to difficulties associated with man­aging tape media and tape's speed compared to D2D (disk-to-disk) tech­nologies. Still, he says, tape represents a "terrific value" for some archiving solutions where low-cost storage is a chief consideration and speed of re­covery is less important. David Hill, Mesabi Group (www.mesabigroup.com) principal, meanwhile, says tape will continue to play a role in backup and recovery as a second or third-level op­tion due to its cost advantages but also because it offers "biological" diversity. "In providing a different media, tape protects against any systematic prob­lems that might affect disk," he says.

The benefits of tape

Among the advantages tape offers over disk storage, Hill says, is that of­fline tape is "protected from logical problems, such as viruses, that can plague online disk." Tape can also offer energy-related benefits, he says, as tape at rest uses no energy; that is unlike disks that are constantly spin­ning in a disk array always consuming energy. Hill cautions, however, that "tapes can only be used for certain purposes, and energy savings don't outweigh the business imperatives that often require the use of disk, even though it is less energy-efficient."

Another tape benefit involves its physical makeup. Disk storage in­volves disk heads that float above spinning platters, while tape heads are stationary and tape moves across the heads in one dimension, Kahn says. Additionally, tape vendors are working on future densities reported to approach 128TB on a cartridge, roughly 32 times what's now avail­able. Disks, meanwhile, might double capacity roughly once every three years or so, he says, and therefore "tape's future seems to be a little more certain than disk's."

What's most important for compa­nies to understand, Kahn says, is the life span of an ATL (automated tape library) compared to that of an all­ disk solution. "ATLs will last for de­cades if maintained," he says. "Yes, you may buy new drives every 3 to 6 years to take advantage of increased densities, but these are modest costs. Tape cartridges clearly can be used for 10 years and likely much longer than that." However, whether scaling up or scaling out, most disk arrays come with a typical three-year warranty, he says, "after which it usually is less expensive to replace the entire array than it is to continue to maintain it at off-warranty maintenance pricing."

Kahn says tape actually can stream data faster than disks, "which is very valuable when bringing back large files." Additionally, it's now possible to store and access files on tape using LTFS (Linear Tape File System) technology, he says. Simply put, this means "each cartridge looks like a mountable file system, with a file index (directory) in a parallel track next to the data tracks. When you mount the cartridge, the index is loaded and discrete files can be ac­cessed directly," Kahn says.

It's now possible to store and access files on tape using LTFS (Linear Tape File System) technology

The future

Looking ahead, Hill says, it's pos­sible a new (perhaps holographic or quantum-based) technology might re­place tape, though nothing seems likely to do so "totally within the next decade, at the very earliest." Application-wise, Hill says tape could serve a role in some big data applications that require re­taining a lot of data in-house for infre­quent sequential analyses of historical data. Tape could also play a big role in cloud computing, he says, "as the last line of defense for backup and disaster recovery, for active archiving where tape-retrieval times are satisfactory, and for deep archiving where you hope to never have to see the data again."

Karp says although big data might offer some opportunities (including long-term storage) for tape, most analytics associated with big data re­quire very rapid input/output, which is tape's weak point. Further, as more analytics associated with big data focus on preemptive vs. reactive approaches, "the ability to stream or otherwise in­gest data at the highest possible rate will become more and more impor­tant." Social media, however, "may be the segment that saves tape," Karp says. "Governmental regulations and corporate governance typically require most if not all companies to keep track of all messages associated with the business, irrespective of what the mes­sages' original format actually was." Here, tape may provide a long-term value, he says.