Although we tend to associate them with the dawn of computing, when a single computer occupied entire rooms, magnetic tapes continue to be an important resource for storing huge amounts of data: they are mainly used to archive files in the long term and that do not require any be consulted frequently (“cold storage”), such as computer backups and archives of various types. This is why magnetic tape technology has never been abandoned and, as the Economist points out, it could have a “surprising future” thanks to some advances that are extending its capabilities.
Magnetic tapes were introduced in computer science in the early 1950s, a few years before the introduction of hard disks, considered more practical because they allowed data to be recovered quickly, with less waiting times associated with rewinding and rewinding the tape. . The computer industry paid more attention to hard drives, with investments in research and development that would gradually lead to disks with an increasingly large capacity to store data.
The best discs available today can store more than 1,000 gigabits (Gb) per square inch (the industry doesn't use the metric system much), determining their commercial success. The demand for these products is very high and is approximately eight times that of magnetic tapes. The availability of alternative systems to classic hard drives, such as solid state memory drives (SSDs), has further increased competition. However, magnetic tapes are less expensive and in many uses are more reliable than hard drives, which tend to have a short life due to the wear of their mechanical parts.
For this reason, several large companies continue to use magnetic tapes and, thanks to some improvements, are confident of being able to integrate them more and more into their data centers. Mark Lantz, who has been working on this technology for years on behalf of IBM, the historic IT company, certainly hopes it. In 2015, Lantz's team made a magnetic tape with a density of 123 gigabits per square inch, two years later it hit 201 gigabits, and at the end of last year it announced that it had made a 317 gigabit per square inch tape. , capable of retaining much more data for the same tape space.
1,000 gigabits per square inch is still a long way off, but when you look at the growth over the past five years, there is still potential for new improvements. Hard drives haven't kept the same pace of growth – storage density doubled about every year in the 1990s, but over the past decade, the growth rate has shrunk to an average of 7.6 percent. There are physical limitations beyond which it is increasingly difficult to go, a problem that for now is less of a problem with magnetic tapes. Their storage density has continued to grow, averaging 34 percent over the past three decades. Within five years, the gap between the two systems could be bridged, making tapes even more in demand.
The Economist explains that Lantz and colleagues worked both on the magnetic material that makes up the tapes (barium ferrite) and on the heads, which read the contents of the tapes, managing to reduce their size by about a third. They then dedicated themselves to the development of some systems to make recording and reading more accurate, reducing the risk of moving the tape even a few nanometers (millionths of a millimeter) vertically, which could lead to incorrect and distorted readings of the data. The results obtained are very encouraging and in the coming years could translate into practical applications to increase the data density on magnetic tapes and make them even more reliable.
The amount of computer data archived every year is more and more. It is estimated that in 2025 alone, four times the data produced in 2019 will be generated. Digital archives, including those in which part of the data is stored via cloud systems, will therefore need magnetic tapes, at least until they improve and become more solutions based on solid state memory (SSD) are economical.
Unlike hard drives and magnetic tapes, SSDs rely on the passage of electrons in transistors, which makes greater storage density possible. The data is read and stored through a flow of electric current, at high speed and without the involvement of mechanical moving parts, which wear out in the long run. However, they are more expensive: they are on average 10 times more expensive per byte stored than hard drives, and up to 50 times more than magnetic tapes. Prices have gradually decreased, but memories of this type still cannot fully compete with more traditional systems in data centers.
