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Fibre Channel Protocol
Fibre Channel Protocol (FCP) is the SCSI interface protocol utilising an underlying Fibre Channel connection. The Fibre Channel standards define a high-speed data transfer mechanism that can be used to connect workstations, mainframes, supercomputers, storage devices and displays. FCP addresses the need for very fast transfers of large volumes of information and could relieve system manufacturers from the burden of supporting a variety of channels and networks, as it provides one standard for networking, storage and data transfer. Some Fibre Channel characteristics are: *Performance from 266 megabits/second to 16 gigabits/second *Support both optical and copper media, with distances up to 10 km. * Small connectors (sfp+ are most common) * High-bandwidth utilisation with distance insensitivity * Support for multiple cost/performance levels, from small systems to supercomputers * Ability to carry multiple existing interface command sets, including Internet Protocol (IP), SCSI, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCSI
Small Computer System Interface (SCSI, ) is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, electrical, optical and logical interfaces. The SCSI standard defines command sets for specific peripheral device types; the presence of "unknown" as one of these types means that in theory it can be used as an interface to almost any device, but the standard is highly pragmatic and addressed toward commercial requirements. The initial Parallel SCSI was most commonly used for hard disk drives and tape drives, but it can connect a wide range of other devices, including scanners and CD drives, although not all controllers can handle all devices. The ancestral SCSI standard, X3.131-1986, generally referred to as SCSI-1, was published by the X3T9 technical committee of the American National Standards Institute (ANSI) in 1986. SCSI-2 was published in August 1990 as X3.T9.2/86-109 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Striping
In computer data storage, data striping is the technique of segmenting logically sequential data, such as a file, so that consecutive segments are stored on different physical storage devices. Striping is useful when a processing device requests data more quickly than a single storage device can provide it. By spreading segments across multiple devices which can be accessed concurrently, total data throughput is increased. It is also a useful method for balancing I/O load across an array of disks. Striping is used across disk drives in redundant array of independent disks (RAID) storage, network interface controllers, disk arrays, different computers in clustered file systems and grid-oriented storage, and RAM in some systems. Method One method of striping is done by interleaving sequential segments on storage devices in a round-robin fashion from the beginning of the data sequence. This works well for streaming data, but subsequent random accesses will require knowledge of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Switched Fabric
Switched fabric or switching fabric is a network topology in which network Node (networking), nodes interconnect via one or more network switches (particularly crossbar switches). Because a switched fabric network spreads network traffic across multiple physical links, it yields higher total throughput than Broadcasting (networking), broadcast networks, such as the early 10BASE5 version of Ethernet and most wireless networks such as Wi-Fi. The generation of high-speed Serial communication, serial data interconnects that appeared in 2001–2004 which provided Point-to-point (telecommunications), point-to-point connectivity between processor and peripheral devices are sometimes referred to as fabrics; however, they lack features such as a message-passing protocol. For example, HyperTransport, the computer processor interconnect technology, continues to maintain a Bus (computing), processor bus focus even after adopting a higher speed physical layer. Similarly, PCI Express is just a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daisy Chain (electrical Engineering)
In electrical and electronic engineering, a daisy chain is a wiring scheme in which multiple devices are wired together in sequence or in a ring, similar to a garland of daisy flowers. Daisy chains may be used for power, analog signals, digital data, or a combination thereof. The term ''daisy chain'' may refer either to large scale devices connected in series, such as a series of power strips plugged into each other to form a single long line of strips, or to the wiring patterns embedded inside of devices. Other examples of devices which can be used to form daisy chains are those based on Universal Serial Bus (USB), FireWire, Thunderbolt and Ethernet cables. Signal transmission For analog signals, connections usually consist of a simple electrical bus and, especially in the case of a chain of many devices, may require the use of one or more repeaters or amplifiers within the chain to counteract attenuation (the natural loss of energy in such a system). Digital signal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arbitrated Loop
The arbitrated loop, also known as FC-AL, is a Fibre Channel topology in which devices are connected in a one-way loop fashion in a ring topology. Historically it was a lower-cost alternative to a fabric topology. It allowed connection of many servers and computer storage devices without using then very costly Fibre Channel switches. The cost of the switches dropped considerably, so by 2007, FC-AL had become rare in server-to-storage communication. It is however still common within storage systems. * It is a serial architecture that can be used as the transport layer in a SCSI network, with up to 127 devices. The loop may connect into a fibre channel fabric via one of its ports. * The bandwidth on the loop is shared among all ports. * Only two ports may communicate at a time on the loop. One port wins arbitration and may open one other port in either half or full duplex mode. * A loop with two ports is valid and has the same physical topology as point-to-point, but still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topology
In mathematics, topology (from the Greek language, Greek words , and ) is concerned with the properties of a mathematical object, geometric object that are preserved under Continuous function, continuous Deformation theory, deformations, such as Stretch factor, stretching, Twist (mathematics), twisting, crumpling, and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself. A topological space is a set (mathematics), set endowed with a structure, called a ''Topology (structure), topology'', which allows defining continuous deformation of subspaces, and, more generally, all kinds of continuity (mathematics), continuity. Euclidean spaces, and, more generally, metric spaces are examples of a topological space, as any distance or metric defines a topology. The deformations that are considered in topology are homeomorphisms and homotopy, homotopies. A property that is invariant under such deformations is a topological property. Basic exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Architecture
Network architecture is the design of a computer network. It is a framework for the specification of a network's physical components and their functional organization and configuration, its operational principles and procedures, as well as communication protocols used. In telecommunication, the specification of a network architecture may also include a detailed description of products and services delivered via a communications network, as well as detailed rate and billing structures under which services are compensated. The network architecture of the Internet is predominantly expressed by its use of the Internet protocol suite, rather than a specific model for interconnecting networks or nodes in the network, or the usage of specific types of hardware links. OSI model The Open Systems Interconnection model (OSI model) defines and codifies the concept of layered network architecture. Abstraction layers are used to subdivide a communications system further into smaller ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicast
In computer networking, multicast is group communication where data transmission is addressed to a group of destination computers simultaneously. Multicast can be one-to-many or many-to-many distribution. Multicast should not be confused with physical layer point-to-multipoint communication. Group communication may either be application layer multicast or network-assisted multicast, where the latter makes it possible for the source to efficiently send to the group in a single transmission. Copies are automatically created in other network elements, such as routers, switches and cellular network base stations, but only to network segments that currently contain members of the group. Network assisted multicast may be implemented at the data link layer using one-to-many addressing and switching such as Ethernet multicast addressing, Asynchronous Transfer Mode (ATM), point-to-multipoint virtual circuits (P2MP) or InfiniBand multicast. Network-assisted multicast may also be impl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunt Group
In telephony, line hunting (or hunt group) is the method of distributing phone calls from a single telephone number to a group of several phone lines. Specifically, it refers to the process or algorithm used to select which line will receive the call. Hunt groups are supported by some PBX phone systems. Also, some phone companies will provide this feature for a small fee (see also: Centrex). In the tariffs of some telephone companies, one may obtain hunting for free, but forward on busy is a charged service. Multi-line hunting ''Multiline hunting'' (sometimes MLH, ''line hunting'' or MHG, ''multiline hunting group'') is a feature that allows multiple telephone lines going into a business to act as a single group, called a ''hunt group''. This type of fallback is a somewhat more complex form of call forwarding. If the line called is busy, the call goes to the next available line. Only if no lines in the group are open does the calling party get a busy signal. Linear hunting I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ... [...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 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 SCSI commands over Fibre Channel networks. FICON is a protocol that transports ESCON commands, used by IBM mainframe computers, over Fibre Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small Form-factor Pluggable Transceiver
Small Form-factor Pluggable connected to a pair of fiber-optic cables Small Form-factor Pluggable (SFP) is a compact, hot-pluggable network interface module format used for both telecommunication and data communications applications. An SFP interface on networking hardware is a modular slot for a media-specific transceiver, such as for a fiber-optic cable or a copper cable. The advantage of using SFPs compared to fixed interfaces (e.g. modular connectors in Ethernet switches) is that individual ports can be equipped with different types of transceiver as required. The form factor and electrical interface are specified by a multi-source agreement (MSA) under the auspices of the Small Form Factor Committee. The SFP replaced the larger gigabit interface converter (GBIC) in most applications, and has been referred to as a Mini-GBIC by some vendors. SFP transceivers exist supporting synchronous optical networking (SONET), Gigabit Ethernet, Fibre Channel, PON, and other c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
