Considered by some to be obsolescent, obsolete or virtually flat-lining, tape backup is still around. Even new hard drive technology and solid state storage cannot match the price point per terabyte stored. Now IBM and Fujifilm have pushed the envelope even further with new tape cartridge that can hold 154 terabytes of data. By comparison, the last time market leader Seagate discussed progress on hard drives in 2012, its objective was for a 6 terabyte 3.5-inch desktop drive, with ‘eventually’ a 60 terabyte version. Does this mean tape is once again snatching itself from the jaws of death – or could it be (gasp) that tape is simply better for volume storage?
Both tape and disk use forms of magnetic recording to store data. Vendors can pack a very large amount of data into each square inch of a disk drive (one terabit per square inch now, says Seagate). This is a critical consideration if disk drives are to remain reasonably compact or indeed mobile for laptops. Tape by comparison squeezes 85.9 billion bits of data into a square inch (approximately 8% of the density of Seagate’s best effort disk drive). But with anywhere up to 846 metres of tape inside an LTO-format (Linear Tape-Open) cartridge, the total recording surface area is still enough to keep tape in the lead in terms of maximum capacity.
Of course, disk retains a sizable advantage with its capability to access data practically immediately in any order and in any stored file. But tape is cheaper, more reliable (less data errors according to manufacturers) and apparently better positioned to store all the Big Data that is being generated. The ‘tape-is-dead’ scare has been disproved so many times now that it looks like tape is simply better in some respects. Will the situation change? That’s unlikely to happen when the main competition is still disk storage. An innovative technique like storing data in DNA might give tape a run for its money, but a commercially viable version has yet to be announced.