If any storage medium deserves the “legacy” moniker, it would be magnetic tape. But unless cloud archiving provides a viable alternative, this artifact of early computing could be around for many more years.
Magnetic tape, one of the earliest forms of storage media for computer systems, has persisted mostly due to its low cost and generally good reliability, depending on who you talk to. A backup mainstay for many decades, it’s now used primarily for archiving data. Its estimated 10- to 20-year lifespan (when treated nicely) makes it ideal, at least in theory, for this purpose.
But as the cost of cloud storage falls, the prospect of archiving in the cloud has become more feasible. It certainly beats out tape in a number of categories, speed of access being the most obvious one. It also offers the same advantages inherent in off-site storage.
Why, then, are many companies still stuck to tape?
Reason No. 1, says Rachel Dines, a senior analyst at Forrester Research Inc., is that tape is still the cheapest way to go for long-term storage.
“There’s definitely a movement of people going to disk and the cloud for archive. The thing is that archive data needs to be stored for such a long period of time for many companies that it’s just not cost-effective for long, long-term archive to be going to the cloud. It’s going to be fairly expensive.”
Cloud providers have attacked the reliability of tape, citing alarming statistics about failure rates. Of these claims, Dines says she is “skeptical of a lot of them.”
“Yes, it’s true, because of the physical nature of the way tape works it can get stretched out, if you don’t store it properly the data can get corrupted because the physical surroundings are so important. I would argue that the issue is less with tape and more with how people treat tape.
“If you put tape in the right environment and store it properly the data will last for 20-plus years. If you take a tape and put it in the glove box of your car, the data might not last a day.”
But Jeff Collier, president of Toronto-based Stage2Data Inc., disagrees. “It’s not a distinction of where data is being stored,” he says , “whether it’s being stored in pristine Iron Mountain conditions or it’s Recall, or at home, or in a glove box, it’s just
to the tape and how the data is being written to that tape.”
“To hold more data on the same size cartridge, they’re becoming more dense. So, essentially, the tracks are becoming thinner and thinner. The problem when you start making the tracks thinner and thinner is that the integrity of those tapes gets depreciated. And it doesn’t matter really how well you’ve kept those tapes.”
He also rejects the contention that tape is cheaper in the long run, given the myriad problems he says can occur with humans handling them over the years.
Blaine Rigler, senior vice-president and general manager of data backup and recovery at Iron Mountain Inc., a company that stores around 79 million tapes for 39,000 customer IDs, explained in an e-mail message why he feels tape is a more reliable medium than spinning disk.
“Bit error rates are considerably better for tape than disk, making tape a more favorable option for applications requiring encryption and compression. Tape media also has a much longer storage life than disk, eliminating the need to migrate data to new media as frequently and reducing labour-intensive conversion costs.”
Once again, Collier vehemently disagrees. He says the fragility of tape should be a key consideration when looking at its longevity over a decade or longer. “The Iron Mountain guy bringing those tapes from point A to point B could possibly drop that box. If you drop a tape from three feet now you can pretty much ensure that the integrity of that tape is gone.
“If you do everything right and you get lucky, maybe 20 years down the road you might be able to recover. The chances are of a person, us, human beings, doing everything right? Slim to none.”
Dines says that, ultimately, certain types of business will find that their archives fit into the cloud better than others. “For companies that need to be constantly mining their archives it does makes sense to keep it in an online format, either disk or cloud. Companies that just need to keep it around for compliance (and) hopefully won’t ever have to touch it, tape, I think, is always going to be the best medium.”