White paper - Alternative Storage Technologies

Alternative Storage Technologies Whitepaper

HARD DISK DRIVE (HDD) What it is: A hard disk is a rapidly rotating disk used for storing digital information. The data is recorded by magnetizing a thin film of ferromagnetic mate- rial. A read/write head on an arm accesses the data when the disk is spinning. Instant access: Hard disks provide instant access to the data and the reading and writing device is an integrated part of the storage medium. They enable cost-efficient storage of large amounts of data, with a storage capacity of up to 10 terabytes per disk (2016). Short durability: High failure rates make hard disks inappropriate for long-term preservation. A recent study projects an average lifespan of six years. 6 It is therefore common to combine a number of disks for redundancy, also known as a RAID. From a mechanical point-of-view, a frequent issue is that the disk will not spin, and the failure rates increase with age. Another common reason for failure is

Solid-State Drives (SSD) use flash memory for digital storage, unlike HDD’s magnetic technology. They are more mechanically robust than HDDs and require less power, but have less data capacity and are more expensive in use. SSD is well suited for portable devices and applications requiring fast data access, but are not considered to have the attributes required for long-term digital preservation.

that the read/write head scrapes the rotating platter and thereby causes damage and data loss. Furthermore, a hard drive is a magnetic storage technology and its magnetic strength will natural- ly deteriorate over time when placed offline for archiving upon a shelf.

6 http://blog.backblaze.com/2013/11/12/how-long-do-disk-drives-last, retrieved November 21st, 2013