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Network Attached Storage
Network-attached storage (NAS) is a file-level computer data storage server connected to a computer network providing data access to a heterogeneous group of clients. In this context, the term "NAS" can refer to both the technology and systems involved, or a specialized computer appliance device unit built for such functionality – a ''NAS appliance'' or ''NAS box''. NAS contrasts with block-level storage area networks (SAN). Overview A NAS device is optimised for serving files either by its hardware, software, or configuration. It is often manufactured as a computer appliance a purpose-built specialized computer. NAS systems are networked appliances that contain one or more storage drives, often arranged into logical, redundant storage containers or RAID. Network-attached storage typically provide access to files using network file sharing protocols such as NFS, SMB, or AFP. From the mid-1990s, NAS devices began gaining popularity as a convenient method of sharing fil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NAS Server
A network access server (NAS) is a group of components that provides remote users with a point of access to a network. Overview A NAS concentrates dial-in and dial-out user communications. An access server may have a mixture of analog and digital interfaces and support hundreds of simultaneous users. A NAS consists of a communications processor that connects asynchronous devices to a LAN or Wide area network, WAN through network and terminal emulation software. It performs both synchronous and asynchronous routing of supported protocols. The NAS is meant to act as a Gateway (telecommunications), gateway to guard access to a protected resource. This can be anything from a telephone Telecommunications network, network, to computer printer, printers, to the Internet. A Client (computing), client connects to the NAS. The NAS then connects to another resource asking whether the client's supplied credentials are valid. Based on that answer the NAS then allows or disallows access to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novell Open Enterprise Server
Open Enterprise Server (OES) is a server operating system published by OpenText. It was first published by Novell in March 2005 to succeed their NetWare product. Unlike NetWare, OES is a Linux distribution—specifically, one based on SUSE Linux Enterprise Server. The first major release of Open Enterprise Server (OES 1) could run either with a Linux kernel (with a NetWare compatibility layer) or Novell's NetWare kernel (with a Linux compatibility layer). Novell discontinued the NetWare kernel prior to the release of OES 2, but NetWare 6.5 SP7, and later SP8, can run as a paravirtualized guest inside the Xen hypervisor (officially supported until 7 March 2012, Novell self-supported until 7 March 2015). OES 1 and OES 2 Novell released OES 1, the first version of OES, on 25 March 2005. Since some users wanted backward compatibility with NetWare, Novell offered two installation options: OES-NetWare and OES-Linux. These are two different operating systems with different kerne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount (computing)
Mounting is a process by which a computer's operating system makes Computer file, files and Directory (computing), directories on a Computer data storage, storage device (such as Hard disk drive, hard drive, CD-ROM, or network share) available for users to access via the computer's file system. In general, the process of mounting comprises the operating system acquiring access to the storage medium; recognizing, reading, and processing file system structure and metadata on it before registering them to the virtual file system (VFS) component. The location in the VFS to which the newly mounted medium was registered is called a "mount point"; when the mounting process is completed, the user can access files and directories on the medium from there. An opposite process of mounting is called unmounting, in which the operating system cuts off all user access to files and directories on the mount point, writes the remaining queue of user data to the storage device, refreshes file sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drive Mapping
Drive mapping is how MS-DOS and Microsoft Windows associate a local drive letter (A-Z) with a shared storage area to another computer (often referred as a File Server) over a network. After a drive has been mapped, a software application on a client's computer can read and write files from the shared storage area by accessing that drive, just as if that drive represented a local physical hard disk drive. Drive mapping Mapped drives are hard drives (even if located on a virtual or cloud computing system, or network drives) that are always represented by names, letter(s), or number(s) and they are often followed by additional strings of data, directory tree branches, or alternate level(s) separated by a "\" symbol. Drive mapping is used to locate directories, files or objects, and programs or apps, and is needed by end users, administrators, and various other operators or groups. Mapped drives are usually assigned a letter of the alphabet after the first few taken, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HyperSCSI
HyperSCSI is an outdated computer network protocol for accessing storage by sending and receiving SCSI commands. It was developed by researchers at the Data Storage Institute in Singapore in 2000 to 2003. HyperSCSI is unlike iSCSI in that it bypassed the internet protocol suite (TCP/IP) and works directly over Ethernet to form its storage area network (SAN). It skipped the routing, retransmission, segmentation, reassembly, and all the other problems that the TCP/IP suite addresses. Compared to iSCSI, this was meant to give a performance benefit at the cost of IP's flexibility. An independent performance test showed that performance was unstable with network congestion. Since HyperSCSI was in direct competition with the older and well established Fibre Channel, and the standardized iSCSI, it was not adopted by commercial vendors. Some researchers at Huazhong University of Science and Technology noted the failure to provide any transport layer In computer networking, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ATA Over Ethernet
ATA over Ethernet (AoE) is a network protocol developed by the Brantley Coile Company, designed for simple, high-performance access of block storage devices over Ethernet networks. It is used to build storage area networks (SANs) with low-cost, standard technologies. Protocol description AoE runs on layer 2 Ethernet. AoE does not use Internet Protocol (IP); it cannot be accessed over the Internet or other IP networks. In this regard it is more comparable to Fibre Channel over Ethernet than iSCSI. With fewer protocol layers, this approach makes AoE fast and lightweight. It also makes the protocol relatively easy to implement and offers linear scalability with high performance. The AoE specification is 12 pages compared with iSCSI's 257 pages. :AoE Header Format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISCSI
Internet Small Computer Systems Interface or iSCSI ( ) is an Internet Protocol-based storage networking standard for linking data storage facilities. iSCSI provides block-level access to storage devices by carrying SCSI commands over a TCP/IP network. iSCSI facilitates data transfers over intranets and to manage storage over long distances. It can be used to transmit data over local area networks (LANs), wide area networks (WANs), or the Internet and can enable location-independent data storage and retrieval. The protocol allows clients (called ''initiators'') to send SCSI commands (''CDBs'') to storage devices (''targets'') on remote servers. It is a storage area network (SAN) protocol, allowing organizations to consolidate storage into storage arrays while providing clients (such as database and web servers) with the illusion of locally attached SCSI disks. It mainly competes with Fibre Channel, but unlike traditional Fibre Channel which usually requires dedicated cabling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibre Channel
Fibre Channel (FC) is a high-speed data transfer protocol providing in-order, lossless delivery of raw block data. Fibre Channel is primarily used to connect computer data storage to Server (computing), servers in storage area networks (SAN) in commercial data centers. Fibre Channel networks form a switched fabric because the switches in a network operate in unison as one big switch. Fibre Channel typically runs on optical fiber cables within and between data centers, but can also run on copper cabling. Supported data rates include 1, 2, 4, 8, 16, 32, 64, and 128 gigabit per second resulting from improvements in successive technology generations. The industry now notates this as Gigabit Fibre Channel (GFC). There are various upper-level protocols for Fibre Channel, including two for block storage. Fibre Channel Protocol (FCP) is a protocol that transports Small Computer System Interface, SCSI commands over Fibre Channel networks. FICON is a protocol that transports ESCON comman ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache (computing)
In computing, a cache ( ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A cache hit occurs when the requested data can be found in a cache, while a cache miss occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs. To be cost-effective, caches must be relatively small. Nevertheless, caches are effective in many areas of computing because typical Application software, computer applications access data with a high degree of locality of reference. Such access patterns exhibit temporal locality, where data is requested that has been recently requested, and spatial locality, where data is requested that is stored near dat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Cluster
A computer cluster is a set of computers that work together so that they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software. The newest manifestation of cluster computing is cloud computing. The components of a cluster are usually connected to each other through fast local area networks, with each node (computer used as a server) running its own instance of an operating system. In most circumstances, all of the nodes use the same hardware and the same operating system, although in some setups (e.g. using Open Source Cluster Application Resources (OSCAR)), different operating systems can be used on each computer, or different hardware. Clusters are usually deployed to improve performance and availability over that of a single computer, while typically being much more cost-effective than single computers of comparable speed or availability. Computer clusters emerged as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
