MEDIA ASSET MANAGEMENT
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Media Asset Storage: it’s in our DNA When it comes to the storage of media assets (or any data, for that matter), whether it’s online or up on the cloud, there’s no doubt that the immediate future of data storage remains magnetic tape. Recent technological advancements have given new life to hard drives, but when it comes to long-term archiving of assets, the tape or hard drive of the future could be something very old, something that everyone has inside them: DNA.
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he first commercial digital-tape storage system, IBM’s Model 726, could store about 1.1 megabytes on one reel of tape. Today, a modern LTO tape cartridge can hold 30 terabytes. Meanwhile, a single robotic tape library can contain up to 556 petabytes of data. While tape doesn’t offer the fast read/write speeds of hard drives, the medium’s advantages are many. For starters, tape is reliable, with error rates four to five orders of magnitude lower than those of hard drives. They are energy efficient: once all the data has been written, the tape cartridge simply sits in a slot in a tape library without consuming any power until it’s needed again. And tape is very secure, with built-in, on-the-fly
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encryption – and if a cartridge isn’t mounted in a drive, the data cannot be accessed or modified. The main reason why tape is so popular is simple economics. Tape storage costs one-sixth the amount you’d have to pay to keep the same amount of data on disks, which is why you find tape systems almost any place where massive amounts of data are being stored. But, as mentioned, tape is slow, and so the development of hard drive technology continues. The longevity of hard disks, and the rapid rise of solid-state drives (SSDs), can be attributed to a continual improvement process to minimise the drawbacks of tape technology. The hard disk game changed dramatically in 2005 with
perpendicular magnetic recording (PMR), where, broadly speaking, magnetised bits stand perpendicular to the head of the hard disk platter instead of lying down, making room for more bits. However, after years of data density improvements using PMR (densities doubled between 2009 and 2015), researchers are once again hitting the physical limits: each magnetic ‘bit’ is becoming too small to reliably hold its data, increasing the potential for corruption. Shingled magnetic recording (SMR), introduced by Seagate in 2014, is one way to fit more data on a disk’s platter. In an SMR disk, when the write head writes a data track, the new track will overlap part of the previously written track, reducing its width and meaning
more tracks can fit on a platter. The thinner track can still be read, as read heads can be physically thinner than write heads. Western Digital launched a 15TB SMR hard drive in 2018 targeting data centres, with plans to increase the capacity per rack by up to 60TB soon. The next big thing is twodimensional magnetic recording (TDMR). This is another Seagate technology, and aims to solve the problem of reading data from tightly packed hard disk tracks, where the read head picks up interference from tracks around the one being read. TDMR disks use multiple read heads to pick up data from several tracks at a time, then work out which data is needed, turning the noise into useful
