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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] |
Computer Data Storage
Computer data storage or digital data storage is a technology consisting of computer components and Data storage, recording media that are used to retain digital data. It is a core function and fundamental component of computers. The central processing unit (CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a storage hierarchy, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away. Generally, the fast technologies are referred to as "memory", while slower persistent technologies are referred to as "storage". Even the first computer designs, Charles Babbage's Analytical Engine and Percy Ludgate's Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles). This distinction was extended in the Von Neumann archite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technical Committee T11
The InterNational Committee for Information Technology Standards (INCITS), (pronounced "insights"), is an ANSI-accredited standards development organization composed of Information technology developers. It was formerly known as the X3 and NCITS. INCITS is the central U.S. forum dedicated to creating technology standards. INCITS is accredited by the American National Standards Institute (ANSI) and is affiliated with the Information Technology Industry Council, a global policy advocacy organization that represents U.S. and global innovation companies. INCITS coordinates technical standards activity between ANSI in the US and joint ISO/ IEC committees worldwide. This provides a mechanism to create standards that will be implemented in many nations. As such, INCITS' Executive Board also serves as ANSI's Technical Advisory Group for ISO/IEC Joint Technical Committee 1. JTC 1 is responsible for International standardization in the field of information technology. INCITS operates th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baud
In telecommunications and electronics, baud (; symbol: Bd) is a common unit of measurement of symbol rate, which is one of the components that determine the speed of communication over a data channel. It is the unit for symbol rate or modulation rate in symbols per second or pulses per second. It is the number of distinct symbol changes (signalling events) made to the transmission medium per second in a digitally modulated signal or a bd rate line code. Baud is related to '' gross bit rate'', which can be expressed in bits per second (bit/s). If there are precisely two symbols in the system (typically 0 and 1), then baud and bits per second are equivalent. Naming The baud unit is named after Émile Baudot, the inventor of the Baudot code for telegraphy, and is represented according to the rules for SI units. That is, the first letter of its symbol is uppercase (Bd), but when the unit is spelled out, it should be written in lowercase (baud) except when it begins a sentence ... [...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, best known for its use with storage devices such as hard disk drives. SCSI was introduced in the 1980s and has seen widespread use on servers and high-end workstations, with new SCSI standards being published as recently as SAS-4 in 2017. 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 optical disc drives, although not all controllers can handle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IPFC
IPFC stands for Internet Protocol over Fibre Channel. It governs a set of standards created in January 2006 for address resolution ( ARP) and transmitting IPv4 and IPv6 network packets over a Fibre Channel (FC) network. IPFC makes up part of the FC-4 protocol-mapping layer of a Fibre Channel system. In IPFC, each IP datagram packet is wrapped into a FC frame, with its own header, and transmitted as a sequence of one or more frames. The receiver at the other end receives the frames, strips the FC headers and reassembles the IP packet. IP datagrams of up to 65,280 bytes in size may be accommodated. ARP packet transmission works in the same fashion. Each IP datagram exchange is unidirectional, although IP and TCP allow for bidirectional communication within their protocols. IPFC is an application protocol that is typically implemented as a device driver in an operating system. IP over FC plays a less important role in storage area networking than SCSI over Fibre Channel or IP over Ethe ... [...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 Packet (information technology), packets from the source Host (network), host to the destination host solely based on the IP addresses in the packet Header (computing), headers. For this purpose, IP defines packet structures that encapsulation (networking), 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 referre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asynchronous Transfer Mode
Asynchronous Transfer Mode (ATM) is a telecommunications standard defined by the American National Standards Institute and International Telecommunication Union Telecommunication Standardization Sector (ITU-T, formerly CCITT) for digital transmission of multiple types of traffic. ATM was developed to meet the needs of the Broadband Integrated Services Digital Network as defined in the late 1980s, and designed to integrate telecommunication networks. It can handle both traditional high-throughput data traffic and Real-time computing, real-time, low-latency content such as telephony (voice) and video.ATM Forum, The User Network Interface (UNI), v. 3.1, , Prentice Hall PTR, 1995, page 2. ATM is a cell switching technology, providing functionality that combines features of circuit switching and packet switching networks by using asynchronous communication, asynchronous time-division multiplexing.McDysan (1999), p. 287. ATM was seen in the 1990s as a competitor to Ethernet and networ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Economies Of Scale
In microeconomics, economies of scale are the cost advantages that enterprises obtain due to their scale of operation, and are typically measured by the amount of Productivity, output produced per unit of cost (production cost). A decrease in unit cost, cost per unit of output enables an increase in scale that is, increased production with lowered cost. At the basis of economies of scale, there may be technical, statistical, organizational or related factors to the degree of Market (economics), market control. Economies of scale arise in a variety of organizational and business situations and at various levels, such as a production, plant or an entire enterprise. When average costs start falling as output increases, then economies of scale occur. Some economies of scale, such as capital cost of manufacturing facilities and friction loss of transportation and industrial equipment, have a physical or engineering basis. The economic concept dates back to Adam Smith and the idea o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multi-mode Optical Fiber
Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Multi-mode links can be used for data rates up to 800 Gbit/s. Multi-mode fiber has a fairly large core diameter that enables multiple light modes to be propagated and limits the maximum length of a transmission link because of modal dispersion. The standard G.651.1 defines the most widely used forms of multi-mode optical fiber. Applications The equipment used for communications over multi-mode optical fiber is less expensive than that for single-mode optical fiber. Typical transmission speed and distance limits are 100 Mbit/s for distances up to 2 km ( 100BASE-FX), 1 Gbit/s up to 1000 m, and 10 Gbit/s up to 550 m. Because of its high capacity and reliability, multi-mode optical fiber generally is used for backbone applications in buildings. An increasing number of users are taking the benefits of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel SCSI
Parallel SCSI (formally, SCSI Parallel Interface, or SPI) is the earliest of the interface implementations in the SCSI family. SPI is a parallel bus; there is one set of electrical connections stretching from one end of the SCSI bus to the other. A SCSI device attaches to the bus but does not interrupt it. Both ends of the bus must be #Termination, terminated. SCSI is a peer-to-peer peripheral interface. Every device attaches to the SCSI bus in a similar manner. Depending on the version, up to 8 or 16 devices can be attached to a single bus. There can be multiple hosts and multiple peripheral devices but there should be at least one host. The SCSI protocol defines communication from host to host, host to a peripheral device, and peripheral device to a peripheral device. The Symbios Logic 53C810 chip is an example of a Peripheral Component Interconnect, PCI host interface that can act as a SCSI target. SCSI-1 and SCSI-2 have the option of parity bit error checking. Starting wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serial Communication
In telecommunication and data transmission, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels. Serial communication is used for all long-haul communication and most computer networks, where the cost of cable and difficulty of synchronization make parallel communication impractical. Serial computer buses have become more common even at shorter distances, as improved signal integrity and transmission speeds in newer serial technologies have begun to outweigh the parallel bus's advantage of simplicity (no need for serializer and deserializer, or SerDes) and to outstrip its disadvantages (clock skew, interconnect density). The migration from PCI to PCI Express (PCIe) is an example. Modern high speed serial interfaces such as PCIe send data several bits at a time using m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HIPPI
HIPPI, short for High Performance Parallel Interface, is a computer bus for the attachment of high speed storage devices to supercomputers, in a Point-to-point link#Point-to-point, point-to-point link. It was popular in the late 1980s and into the mid-to-late 1990s, but has since been replaced by ever-faster standard interfaces like Fibre Channel and 10 Gigabit Ethernet. HIPPI was the first “near-gigabit” (0.8 Gbit/s) (American National Standards Institute, ANSI) standard for network data transmission. It was specifically designed for supercomputers and was never intended for mass market networks such as Ethernet. Many of the features developed for HIPPI were integrated into such technologies as InfiniBand. What is remarkable about HIPPI is that it came out when Ethernet was still a 10 Mbit/s data link and SONET at OC-3 (155 Mbit/s) was considered leading edge technology. The first HIPPI standard (HIPPI-PH) defined a 50-pair (100-wire) unidirectional twis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
