Is Glass Destined to Be the New Data Archival Solution?

During the Microsoft Ignite 2019 keynote, Microsoft CEO Satya Nadella announced that the company had been experimenting with using glass as a data archival solution, or medium for cold data storage. Nadella went on to say that Microsoft has partnered with Warner Bros., and had preserved the 1978 movie “Superman” on a 75mm x 75mm x 2mm wafer of glass. For those who prefer empirical measurements, the glass storage device is roughly about 3 inches by 3 inches, or just a little bit smaller than an old-school floppy disk. The glass storage wafers are less than one-tenth of an inch thick.

There are any number of reasons to be skeptical of the idea of using glass as a data storage medium. For starters, the fact that Microsoft chose to encode “Superman” in glass was undoubtedly a publicity stunt that was surely intended to invoke memories of the “memory crystals” used in some of the Superman movies.

Another reason for skepticism about glass as a data archival solution is that glass storage disks like the one that Nadella talked about are capable of holding a mere’ 75.6 GB of data. That’s roughly 150% of the capacity of a Blu-ray disk (but 53,750 times more storage than the similarly sized floppy disk from so long ago). In today’s world, 75 GB really isn’t very large. Many of today’s consumer electronic devices can accommodate 256 GB micro SD cards that are far smaller than the glass storage disks

The most obvious reason for skepticism is that glass can be fragile, but, despite this and all of the other reasons for doubt I’ve laid out, the technology may actually be a viable cold data storage solution.

The researchers at Microsoft have been hard at work ensuring that the glass disks will be durable enough to survive in the real world. According to Nadella, Microsoft has been subjecting the glass disks to various tortures to ensure their durability. The disks have been baked in ovens, boiled in water, microwaved, and even scratched with steel wool.

As impressive as these durability tests may be, Nadella did not mention anything about drop tests. Ultimately, the tendency to shatter on impact may prove to be the device’s Achilles’ heel, but that remains to be seen. It is encouraging to see Microsoft working so hard to make sure that the glass disks are as durable as possible.

And while it is true that the glass storage disks have a comparatively miniscule capacity, there are at least two things one must keep in mind. First, the glass disks are currently being produced as a part of a research project. They are not yet ready for production use. As the project matures, it seems inevitable that the medium’s storage capacity will increase.

The other important consideration, and this is the big one, is that storage capacity is of secondary importance. While it would be nice to be able to store a petabyte or more of data on a thin glass wafer that you can hold in the palm of your hand, the real benefit to using glass storage is the medium’s longevity.

Although nobody really knows for sure how long a glass storage disk will last, conventional wisdom states that the disks could easily preserve data for centuries (or even longer).

Some have said that 500 years is a conservative estimate of the disk’s lifespan. To put this into perspective, imagine having information from the 1500s, perfectly preserved in glass for our use today. Granted, the technology to actually read the data may not exist in 500 years, but that is a separate matter.

Today, cold storage mediums such as tape (or film, if we are talking about “Superman”) have to be stored in climate-controlled vaults to prevent the medium from degrading. Glass-based storage is unlikely to require such careful storage. And, glass is made from sand, which is one of the most abundant materials on Earth.

Today, glass-based storage might best be described as expensive and imperfect. Over time, though, glass may very well prove to be the absolute best medium for long-term, immutable data storage.