SOLID STATE STORAGE DEVICES
Solid state storage (SSS) is a type of computer storage media that is made from silicon microchips. SSS stores data electronically instead of magnetically, as spinning hard disk drives or magnetic oxide tape do.
Solid-state storage can be found in three form factors: solid state drives (SSD), solid state cards (SSC), solid state modules (SSM). An important advantage of solid-state storage is the fact that it contains no mechanical parts, allowing data transfer to and from storage media to take place at a much higher speed and providing a more predictable lifespan for the storage media.
In addition to providing faster and more consistent input/output times, solid-state storage media offers the same levels of data integrity and endurance as other electronic devices and requires less power and cooling than its electromechanical equivalents. It also generally weighs less.
Although solid-state storage technology is not new, interest in how the technology can be used to improve enterprise storage has been relatively recent. Since the turn of this century, processor speeds have continued to increase dramatically while read and write times for mechanical hard disks have not.
Today’s CPUs can process data much faster than hard disk drive storage can supply it. The resulting lag time is known as latency, and one way enterprise administrators have traditionally dealt with high storage latency is by short-stroking the disk drives. Short-stroking is done by deliberately limiting the disk drive capacity so that the disk drive actuator has to move the heads across a smaller number of tracks, reducing seek time. Environments that implement short-stroking typically have to make up for the reduced capacity utilized in each disk drive by increasing the number of disk drives in these configurations. By contrast, SSS devices have zero seek time so their latencies are considerably less, which makes them faster than hard disk drives.
A solid-state drive (sometimes improperly referred to as a "solid-state disk" or "electronic disk") is data storage devices that use integrated circuits assemblies as memory to store data persistently. SSD technology uses electronic interfaces compatible with traditional block input/output hard disk drives. SSDs do not employ any moving mechanical components, which distinguishes them from traditional magnetic disks such as hard disk drives (HDDs) or floppy disks, which are electromechanical devices containing spinning disks and movable read/write heads. Compared with electromechanical disks, SSDs are typically less susceptible to physical shock, are silent, and have lower access time and latency, but are, at 2011 market prices, more expensive per unit of storage. The prices have continued to decline in 2012. SSDs share the I/O interface technology developed for hard disk drives, thus permitting simple replacement for most applications.
As of 2010, most SSDs use NAND-based flash memory, which retains data without power. For applications requiring fast access, but not necessarily data persistence after power loss, SSDs may be constructed from random-access memory (RAM). Such devices may employ separate power sources, such as batteries, to maintain data after power loss.
Hybrid drives combine the features of SSDs and HDDs in the same unit, containing a large hard disk drive and an SSD cache to improve performance of frequently accessed data. These devices may offer near-SSD performance for many applications.
Solid state drives have set new challenges for data recovery companies, as the way of storing data is much more non-linear and complex than of hard disk drives. The strategy the drive operates by internally can largely vary between manufacturers and, the TRIM command zeroes the whole range of a deleted file. Wear leveling also means that the physical and virtual locations of data pieces differ.
As for secure deletion of data, using the ATA Secure Erase command...
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