To stay up-to-date in the battle against hackers, some companies are turning to a 1950s technology.

Storing data on tape seems impossibly inconvenient in an age of easy-access cloud computing. But that is the big security advantage of this vintage technology, since hackers have no way to get at the information. The federal government, financial-services firms, health insurers and other regulated industries still keep tape as a backup to digital records.

Now a range of other companies are returning to tape as hackers get smarter about penetrating defenses—and do much more damage when they do get in.

Rob Pritchard, founder of the Cyber Security Expert consulting firm and associate fellow at the Royal United Services Institute think tank, has noticed the steady resurgence of tape as part of best-practice backup strategies.

“Companies of all sizes must be able to restore data quickly if needed,” he says, “but also have a robust, slower-time, recovery mechanism should the worst happen.”

Pritchard, who works with a range of organizations to improve corporate cybersecurity practices, says: “A good backup strategy will have multiple layers. Cloud and online services have their place, but can be compromised.”

Companies started using digital tape as far back as the 1950s, when it was largely the only choice available for reliable, large-scale data storage. Companies sent full reels to an on-site library for storage until needed.

As computers got slimmer and more powerful, so did tape, moving from reels to compact cartridges able to store much more data and making storage and transport more convenient. Still, companies moved away from tape to digital records and more recently the cloud—where companies don’t even need to maintain servers to keep backup data, let alone a storage facility for tape cartridges.

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Some security experts and tape users argue that the medium has big advantages over other forms of storage—including a higher reliability rate than hard drives and a lifespan in excess of 30 years. The total cost of ownership per terabyte is also the lowest of any storage medium. Top-of-the-line tapes can hold up to 15 terabytes and can be archived in third-party locations at a fraction of the cost of cheapest cloud storage.

PDP Group, a provider of insurance policies for auto dealerships, uses tape as its primary backup. “Tape is our main form of backup and recovery” says Computer Operations and Network Manager Rick Heisey. “We remain confident that tape will continue to be the most reliable and cost-effective means of protecting our company data.”

The company says the tapes are encrypted for security purposes, but can be easily retrieved and the data easily restored when required.

Marc Langer, founder and president of Recovery Point Systems, a business continuity and disaster recovery firm, says tape isn’t meant to be the primary way for companies to restore data lost to hackers, but it can be a safe choice.

“Most people are looking for convenience and the cloud is convenient,” he says. “Tape isn’t inefficient or ineffective, but it can be inconvenient. Good security is almost always inconvenient.”