Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to a heterogeneous group of clients. NAS doesnot only operate as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. It’s often manufactured as a computer appliance ? a specialized computer built from the ground up for storing and serving files ? rather than simply a general purpose computer being used for the role.
A NAS unit is a computer connected to a network that provides only file-based data storage services to other devices on the network. Although it may technically be possible to run other software on a NAS unit, it is not designed to be a general purpose server. For example, NAS units usually do not have a keyboard or display, and are controlled and configured over the network, often using a browser.
A full-featured operating system is not needed on a NAS device, so often a stripped-down operating system is used. For example, FreeNAS, an open source NAS solution designed for commodity PC hardware, is implemented as a stripped-down version of FreeBSD. NAS systems contain one or more hard disks, often arranged into logical, redundant storage containers or RAID.
RAID (redundant array of independent disks, originally redundant array of inexpensive disks) is a storage technology that combines multiple disk drive components into a logical unit for the purposes of data redundancy and performance improvement. Data is distributed across the drives in one of several ways, referred to as RAID levels, depending on the specific level of redundancy and performance required.
RAID is now used as an umbrella term for computer data storage schemes that can divide and replicate data among multiple physical drives: RAID is an example of storage virtualization and the array can be accessed by the operating system as one single drive. The different schemes or architectures are named by the word RAID followed by a number (e.g. RAID 0, RAID 1). Each scheme provides a different balance between the key goals: reliability and availability, performance and capacity. RAID levels greater than RAID 0 provide protection against unrecoverable (sector) read errors, as well as whole disk failure.
A hard drive (HDD) is a data storage device used to store and retrieve digital information using rapidly rotating disks coated with magnetic material. An HDD keeps its data even when powered off. Data is read in a random-access manner, meaning individual blocks of data can be stored or retrieved in any order rather than sequentially. An HDD consists of one or more rigid (“hard”) rapidly rotating disks with magnetic heads arranged on a moving actuator arm to read and write data to the surfaces.
Introduced by IBM in 1956, HDDs became the dominant storage device for general purpose computers by the early 1960s. Continuously improved, HDDs have maintained this position into the modern era of servers,personal computers and laptops. More than 200 companies have produced HDD units, though most units are manufactured by Seagate, Toshiba and Western Digital. Worldwide revenues for HDD shipments are expected to reach $33 billion in 2013, a decrease of approximately 12% from $37.8 billion in 2012.
The primary characteristics of an HDD are its capacity and performance. Capacity is specified in unit prefixes corresponding to powers of 1000: a 1-terabyte (TB) drive has a capacity of 1,000 gigabytes (GB; where 1 gigabyte = 1 billion bytes). Typically, some of an HDD’s capacity is unavailable to the user because it’s used by the file system and the computer operating system, and possibly inbuilt redundancy for error correction and recovery.
ioSafe is a manufacturer of disaster protected hard drives and network attached storage NAS appliances. ioSafe designs and builds award-winning fireproof and waterproof data storage solutions. Our products are used for physical protection, private/hybrid cloud-based backup and disaster recovery solutions for businesses of all sizes, creative professionals and home users. Like an aircraft black box for critical data, ioSafe improves recovery point and time objectives while reducing costs and simplifying infrastructure.