Solid-state storage (SSS) is an increasingly popular backup alternative to traditional storage technologies such as the hard disk drive (HDD), compact disc, rewriteable (CD-RW), and digital versatile disc RAM (DVD-RAM).
All SSS devices, also called solid-state drives (SSDs), function entirely by electronic means, and therefore they lack internal moving parts. In theory, this characteristic should allow SSS devices to perform faster, longer, and more reliably than devices that employ mechanical components. In practice, the situation is more complex because optimum performance requires dovetailing of the underlying technologies.
The following table lists and compares several emerging and currently available SSS technologies. Some engineers and authors, when referring to certain SSS technologies, use the term memory (a technical misnomer) in place of the correct term, storage.
|Conductive metal-oxide (CMOx)||A nonvolatile storage medium in which oxygen ions migrate between conductive and insulating metal-oxide layers within a single chip.||Emerging technology|
|Enterprise multi-level-cell (eMLC) flash||A form of multi-level-cell (MLC) flash that offers an increased number of program/erase (PE) cycles for extended life and reliability.||Data storage for medium and large business high performance computing.|
|Flash-based solid-state storage||Any data repository or system that uses flash memory. The size and complexity of such systems ranges from USB drives to enterprise-class array-based memory systems.||Data storage for a wide variety of users and environments where performance is crucial.|
|Magnetoresistive random-access memory (MRAM)||A method of storing data bits using magnetic charges instead of the electrical charges used by dynamic RAM (DRAM).||High-density solid-state storage; emerging technology.|
|Multi-level-cell (MLC) flash||An approach to flash memory in which two data segments can be written to the same cell, thereby doubling the storage capacity of single-level cell (SLC) flash.||Used in standalone, hybrid and all-flash storage systems, spanning personal, small business and enterprise computing.|
|NAND flash memory||Flash memory technology or devices constructed using NAND logic gates.||High speed storage for all types of devices, including those for consumers (personal electronics), small businesses and enterprises.|
|NOR flash memory||Low-density, random-access flash memory technology or devices constructed using NOR logic gates.||Typically used in mobile phones and personal electronics devices to store executable code.|
|Phase-change memory (PCM)||A form of computer RAM (random-access memory) that stores data by altering the state of the matter rapidly back and forth between amorphous and crystalline on a microscopic scale.||Emerging technology noted for exceptional switching speed and high storage density.|
|RAM-based solid-state storage||A volatile solid-state storage media based on RAM technology that is relatively insensitive to the number of PE cycles.||High-speed computer memory applications for personal, business, and government environments.|
|Resistive RAM (RRAM)||A form of nonvolatile storage that operates by changing the resistance of a specially formulated solid dielectric material.||Emerging technology noted for exceptional switching speed and high storage density.|
|Single-level-cell (SLC) flash||A nonvolatile solid-state storage device or technology that provides enhanced reliability and performance relative to MLC and eMLC flash media.||High-speed data storage for medium and large businesses and government agencies.|