Solid state drives or devices (SSDs) are used to implement non-volatile memory in many relatively high-performance computer systems, including, for example, data center servers. In general, these computer systems/servers are periodically replaced with newer models. Memory components such as NAND flash memory-based SSDs conventionally have a significant amount of useful life left when the computer systems are retired. For example, a system with a three-year warranty may utilize SSDs that have a five-year warranty, in which case the system (including its SSD components) may be retired even though the SSDs are still functional and covered by their warranty. Also, SSDs may be removed from service when their warranty expires even if they are still functional; that is, an SSD's actual lifetime may extend well beyond the period covered by its warranty. In general, events such as these can result in regular disposal of SSDs that could otherwise still be used.
Businesses, government agencies, and other types of organizations store tremendous amounts of data on SSDs. Large amounts of that data may be confidential or proprietary and must be protected against unauthorized access and use. SSDs being removed from service can be physically destroyed so that the data cannot be read. However, physical destruction of SSDs has a number of drawbacks. First, it can be time-consuming and labor-intensive. Also, as noted above, SSDs removed from service may still be functional and thus could still be used in some applications even if their performance is somewhat degraded. However, physical destruction of SSDs means that they cannot continue to be used. Large numbers of SSDs are retired with some remaining useful life; costs would be reduced if those SSDs were instead used in less demanding applications in place of newer SSDs.
Another drawback to physical destruction is that the data stored on an SSD, or at least some portions of that data, may still be accessible. Data is stored in SSDs on flash memory dies. The dies are getting smaller and smaller, so it is possible for an entire die to remain intact and the data on that die to remain readable even if the SSD is broken into small pieces. Also, some parts of a broken die may remain intact and the data on those parts may still be readable; even a small part of a broken die may contain a large amount of readable data. Thus, physical destruction may not be an effective way of protecting data.
An alternative to physical destruction is to erase the data from SSDs before the SSDs are removed from the computer system/server. This method allows SSDs to be used in other applications. However, erasing the data takes a long time and consumes large amounts of computational resources and power, and is therefore inefficient.