The technology world today is rife with sharing and distribution of digital media from one user to another. Additionally, multiple users demand access to the media at the same time, be they customers, clients, or workers within an organization. Moreover, organizations collect customer data for the purpose of data mining and therefore improvement of customer service, and would thus need to store both the structured and unstructured data for future use. Even more, is that laws require organizations to keep digital records. Network-attached storage (NAS) provides a solution to this dilemma. Advances in the system have seen the systems become feature-rich, even as they are offered as either standard computer-based systems or embedded systems.
Keywords: NAS, Servers,
Sources Used in Network-Attached Storage
The technology world today is rife with sharing and distribution of digital media from one user to another. Additionally, multiple users demand access to the media at the same time, be they customers, clients, or workers within an organization. Moreover, organizations collect customer data for the purpose of data mining and therefore improvement of customer service, and would thus need to store both the structured and unstructured data for future use. Even more, is that laws require organizations to keep digital records. With the increase in sharing, distribution, and storage of digital media, servers have continually been under strain for space, given the capacity on the hard disk that such media take (Connor, 2013). This prompted the movement of more data into online platforms through networks to allow access to the data. Network-attached storage (NAS) is an option that allows the storage of data for networks and provides access to the data stored to a diverse range of clients within a given network (Jacobi, 2012). NAS, therefore, becomes the hub for file access, with users’ file requests sidestepping the server, therefore, enhancing bandwidth and eliminating blockages, while at the same time using less powerful hardware as what may be required for a full-scale server. Either these are provided by the embedded or the standard computer-based Network-attached Storage.
NAS: Literature Review
As a system specially built or designed for file sharing within a network, NAS provides businesses and organizations with the necessary expansion for storage, especially for those that require higher capacity storage of data to be used by multiple users (Jacobi, 2012). The two varieties of NAS that exist are the commercial and non-commercial NAS with divergence in the type of operating system that they run. Most commercial NAS is preinstalled with a miniaturized version of an operating system, ingeniously embedded with the preinstalled hardware. For the non-commercial NAS, however, there is a heavy modification of the preconfigured software, largely on a do-it-yourself basis (Shelly &Vermaat, 2012).
According to Connor (2013), a distinction can also be made on the NAS system based on its scalability and cost. This difference divides NAS into entry-level, midrange, and enterprise categories in relation to the capacity of each of the systems. The distinction has 300GB, 300GB-1.2 terabyte, and more than 1.2 TB of capacity for the entry-level, mid-range level, and enterprise levels of NAS respectively. Most entry and midrange level NAS are Windows-powered and are therefore the most appropriate for networks based on the Windows system (Connor, 2013). High-end enterprise NAS systems in contrast have more features. These include fault tolerance, hot-swappable drives, and data duplication between sites. The performance of the high-end NAS is therefore adequate for running mission-critical applications, such as databases and virtual transactions processing applications (Connor, 2013).
In the further distinction of NAS systems apart from the commercial and non-commercial, entry-level midrange, and enterprise categories, NAS can also be distinguished as either standard-based computer systems or embedded systems. This distinction follows the exclusivity of administration of the storage systems in their support for multiple file-based protocols (Lehmann, 2007). The embedded system, therefore, offers more administrative control within the network, allowing the administrator to determine what files are accessible to what users, as well as determining the modes and locations of different files within the system.
The distinctions notwithstanding, at the base of NAS are the different components, which cut across the board for all the systems regardless of whether they are commercial or non-commercial, embedded or standard computer systems. The components include a central processing unit, the storage capacity available for users within a network, locational storage for the operating system, RAM for the OS, and an interface for networked communication (Carpenter 2011). A RAID system is yet another feature of NAS systems, allowing, within the operating system, the pooling of various storage disks and making them appear as a single storage disk to the operating system (Carpenter 2011).
Given such advances in NAS, the system is becoming more popular across the globe as more companies are looking at the management of NAS systems. NAS particularly addresses the segregated silo approach, with the possibility of amalgamation (Connor, 2013). Although the challenge in getting the new phenomenon lies in the migration of files from one place to another and the speed at which one can manage multiple NAS appliances, new companies in the industry are fast providing solutions to the dilemma. Using the RAID system, the new companies, such as iSilon and Z-force among others have designed software and hardware for NAS appliances, which are embedded on top of customary NAS, allowing the access and management of geographically separate NAS appliances as a single device (Connor, 2013). Moreover, with the amalgamation of NAS in different locations possible through a single highly available and scalable NAS system, a singular NAS solution has the capacity to trade off many general-purpose servers dedicated to network file serving (Drakard, 2005). Such advances allow for the streamlining of operations and therefore eradicating latency problems in the access of distributed NAS systems, as well as in cutting infrastructural costs.
With such advances in NAS, it is, therefore, easier to choose between NAS and SAN (Storage area network). Thus, while SAN is operating system dependent given that blocks of data are largely moved, NAS offers access to applications that require sharing of access of the same files, especially for read-only access across different platforms given that it (NAS) is not operating system reliant (Drakard, 2005). Therefore, given that file sharing and serving are largely requests from multiple heterogeneous servings running simultaneously, NAS provides the best solution for such a scenario. This is similarly the case for media serving where multiple users will require access to a similar clip or movie. Given that many servers will point to the same file in such a case, NAS provides the best solution, satisfying the user in both performance and capacity requirements (Connor, 2013). Moreover, as earlier stated, NAS provides scalability and manageability, eliminating the need to clone data to individual servers, as well as having only a few copies of the original file. With scalability, NAS, therefore, allows parallel running of systems as it allows point-in-time access of copies of a file (Oehme et al., 2008).
Sources of NAS
NAS operations are available for different operating system platforms. While some of the operating systems are proprietary, others are open-source projects that provide equally good performances. However, the two most common sources of NAS are either the embedded or the standard computer-based systems. The choice of either of the sources and the operating system to be used will depend on the performance level that an individual or organization wants to achieve as well as the number of resources available (Nagle et al., 2009).
The standard computer-based systems, as one source of NAS, are faster but costly. These systems run on x64/x86 based processors with pre-configuration from the manufactures. Conversely, it is also possible to construct such systems from standard or specific computer parts (Nagle et al., 2009). The fact that these are standard-based computer systems ensures that they have higher performance given their high memory, in addition to the capability for expansion. Within these systems are varied OSes. Among these are Linux (modified versions) along with FreeBSD. Both Windows and Apple also offer operating systems for running the systems within their standard server and computer operating systems. Additionally, NAS are offered in a diverse range of designs that include rack servers, personal computers, and commercial trademarked devices, in addition to smaller devices varying in both price and performance.
On the other hand, embedded systems are based on microprocessors, with their design and build meant for the fulfillment of multiple roles. The system is however not limited in functionality as with proper configuration can perform other general purposes as a PC (Heath, 2013). Given their cost-effectiveness and relatively low performance, embedded systems are suitable for both homes and small offices. Part of the recommendation for homes and small offices is their low consumption in power, low cost requires less space as well as less technical expertise (Choubey&Singhal, 2012).
Largely, these systems have no video outputs, in addition to only a limited operating system, embedded with the system. They however allow for administrative functionality and control through the network using a web browser. It is however possible to make modifications to the system for administrative features through a serial port connection (Choubey&Singhal, 2012). Further, varieties of manufacturers produce and sell these systems with options for both the upgradable and non-upgradable options. There have however been many developments in the embedded systems include routers accessing storage devices through USB ports and providing NAS functionalities, albeit with poor performance. Moreover, many of the new embedded NAS has several USB ports with single gigabit Ethernet connections for the provision of network access to USB storage devices with connections to them (Choubey & Singhal, 2012).
Given the availability of the two NAS systems, the selection of the OS becomes the next step. A choice between the embedded and the computer-based system is largely on the cost and the type of enterprise using the system. For the operating system, however, the determinant lies in the system requirements, the price tag, support from experts, and the extended features required. There exist both open source and proprietary OSes for the NAS systems, from which to choose, and which perform well. The OS performs the intelligence of connecting the file system with the file storage device, and therefore largely requires compatibility with the system, although it should be able to offer access to users running any operating system over the server (Hernandez et al., 2002).
The increase in digital media demand across the technology world from both users and clients has necessitated novel methods of data storage for access to users without downtime issues for the user, as well as putting less strain on servers. NAS provides a viable solution to individuals, organizations, and corporations, who want to store, manage and access data over a network, and at the same time offer scalability of the data to users. Computer-based and embedded NAS offer sources for NAS. Both are versatile and offer a diverse range of storage capacity, capability, and performance, for which users can choose. Regard the operating system running; compatibility, cost, and performance are key in choosing the most appropriate OS for the NAS system.
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Nagle, D. F. (2009). Network Support for Network-Attached Storage. Proceedings of Hot Interconnects 2009, August 18 – 20, 1999, Stanford University, Stanford, California, U.S.A
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Shelly, G, B. &Vermaat, M. E. (2012). Discovering Computers Complete: Your Interactive Guide to the Digital World. Boston, MA: Course Technology, Cengage Learning