1.
Grid Systems Corporation
–
The company went public in March 1981. It was located at 47211 Lakeview Boulevard, Fremont, California 94537, the GRiD name with the unusual lowercase i in the middle was the result of discussion between John Ellenby, Glenn Edens and John Ellenbys wife, Gillian Ellenby, who pushed for the final choice. The lowercase i was a note of thanks to Intel for helping in the early days GRiD developed and released several pioneering ideas and its operating system was based on MS-DOS. A GRiD Compass 1101 was the first laptop in space, required special modification to add a fan to pull air through the case. Subsequently a GRiD1530 flew on STS-29 in March 1989, oldComputers. net called the 1982 GRiD Compass 1101 the grand-daddy of all present-day laptop computers. It had 256k RAM, an 8086, 320x240 screen, in 1988, Tandy Corporation purchased GRiD. AST Computer acquired the company, which then was acquired by Samsung, Edens co-founded Waveform Corp and in 2003 joined the board of F5 Networks Inc. John Ellenby went on to co-found the companies Agilis and Augmented Reality pioneer GeoVector
2.
Distributed computing
–
Distributed computing is a field of computer science that studies distributed systems. A distributed system is a model in which components located on networked computers communicate and coordinate their actions by passing messages, the components interact with each other in order to achieve a common goal. Three significant characteristics of distributed systems are, concurrency of components, lack of a global clock, examples of distributed systems vary from SOA-based systems to massively multiplayer online games to peer-to-peer applications. A computer program that runs in a system is called a distributed program. There are many alternatives for the message passing mechanism, including pure HTTP, RPC-like connectors, Distributed computing also refers to the use of distributed systems to solve computational problems. In distributed computing, a problem is divided into many tasks, each of which is solved by one or more computers, which communicate with each other by message passing. The terms are used in a much wider sense, even referring to autonomous processes that run on the same physical computer. The entities communicate with each other by message passing, a distributed system may have a common goal, such as solving a large computational problem, the user then perceives the collection of autonomous processors as a unit. Other typical properties of distributed systems include the following, The system has to tolerate failures in individual computers. The structure of the system is not known in advance, the system may consist of different kinds of computers and network links, each computer has only a limited, incomplete view of the system. Each computer may know one part of the input. Distributed systems are groups of networked computers, which have the goal for their work. The terms concurrent computing, parallel computing, and distributed computing have a lot of overlap, the same system may be characterized both as parallel and distributed, the processors in a typical distributed system run concurrently in parallel. Parallel computing may be seen as a tightly coupled form of distributed computing. In distributed computing, each processor has its own private memory, Information is exchanged by passing messages between the processors. The figure on the right illustrates the difference between distributed and parallel systems, figure shows a parallel system in which each processor has a direct access to a shared memory. The situation is complicated by the traditional uses of the terms parallel and distributed algorithm that do not quite match the above definitions of parallel. The use of concurrent processes that communicate by message-passing has its roots in operating system architectures studied in the 1960s, the first widespread distributed systems were local-area networks such as Ethernet, which was invented in the 1970s
3.
Computer cluster
–
A computer cluster consists of a set of loosely or tightly connected computers that work together so that, in many respects, they can be viewed as a single system. Unlike grid computers, computer clusters have each set to perform the same task. The components of a cluster are usually connected to each other through fast local area networks and they have a wide range of applicability and deployment, ranging from small business clusters with a handful of nodes to some of the fastest supercomputers in the world such as IBMs Sequoia. The desire to get more computing power and better reliability by orchestrating a number of low-cost commercial off-the-shelf computers has given rise to a variety of architectures, the computer clustering approach usually connects a number of readily available computing nodes via a fast local area network. g. Via a single system image concept, Computer clustering relies on a centralized management approach which makes the nodes available as orchestrated shared servers. It is distinct from other such as peer to peer or grid computing which also use many nodes. A computer cluster may be a simple system which just connects two personal computers, or may be a very fast supercomputer. A basic approach to building a cluster is that of a Beowulf cluster which may be built with a few computers to produce a cost-effective alternative to traditional high performance computing. An early project that showed the viability of the concept was the 133-node Stone Soupercomputer, the developers used Linux, the Parallel Virtual Machine toolkit and the Message Passing Interface library to achieve high performance at a relatively low cost. Although a cluster may consist of just a few personal computers connected by a simple network, greg Pfister has stated that clusters were not invented by any specific vendor but by customers who could not fit all their work on one computer, or needed a backup. Pfister estimates the date as some time in the 1960s, the first production system designed as a cluster was the Burroughs B5700 in the mid-1960s. This allowed up to four computers, each with one or two processors, to be tightly coupled to a common disk storage subsystem in order to distribute the workload. Unlike standard multiprocessor systems, each computer could be restarted without disrupting overall operation, the first commercial loosely coupled clustering product was Datapoint Corporations Attached Resource Computer system, developed in 1977, and using ARCnet as the cluster interface. Clustering per se did not really take off until Digital Equipment Corporation released their VAXcluster product in 1984 for the VAX/VMS operating system, the ARC and VAXcluster products not only supported parallel computing, but also shared file systems and peripheral devices. The idea was to provide the advantages of parallel processing, while maintaining data reliability, two other noteworthy early commercial clusters were the Tandem Himalayan and the IBM S/390 Parallel Sysplex. Within the same frame, while computer clusters used parallelism outside the computer on a commodity network. Following the success of the CDC6600 in 1964, the Cray 1 was delivered in 1976, while early supercomputers excluded clusters and relied on shared memory, in time some of the fastest supercomputers relied on cluster architectures. Computer clusters may be configured for different purposes ranging from general purpose business needs such as web-service support, in either case, the cluster may use a high-availability approach
4.
Homogeneity and heterogeneity
–
Homogeneity and heterogeneity are concepts often used in the sciences and statistics relating to the uniformity in a substance or organism. A material or image that is homogeneous is uniform in composition or character, the alternate spellings homogenous and heterogenous are commonly, but incorrectly, used. Heterogenous meanwhile is a term primarily confined to pathology which refers to the property of an object in the body having its origin outside the body, the concepts are the same to every level of complexity, from atoms to populations of animals or people, and galaxies. Hence, an element may be homogeneous on a larger scale and this is known as an effective medium approach, or effective medium approximations. Various disciplines understand heterogeneity, or being heterogeneous, in different ways, heterogeneous solids, liquids, and gases may be made homogeneous by melting, stirring, or by allowing time to pass for diffusion to distribute the molecules evenly. For example, adding dye to water will create a solution at first. Entropy allows for heterogeneous substances to become homogeneous over time, a heterogeneous mixture is a mixture of two or more compounds. Examples are, mixtures of sand and water or sand and iron filings, a rock, water and oil, a salad, trail mix. A mixture can be determined to be homogeneous when everything is settled and equal, various models have been proposed to model the concentrations in different phases. The phenomena to be considered are mass rates and reaction, homogeneous reactions are chemical reactions in which the reactants and products are in the same phase, while heterogeneous reactions have reactants in two or more phases. Reactions that take place on the surface of a catalyst of a different phase are also heterogeneous, a reaction between two gases or two miscible liquids is homogeneous. A reaction between a gas and a liquid, a gas and a solid or a liquid and a solid is heterogeneous, earth is a heterogeneous substance in many aspects. E. g. rocks are inherently heterogeneous, usually occurring at the micro-scale and mini-scale, in algebra, homogeneous polynomials have the same number of factors of a given kind. This can cause problems in attempts to summarize the meaning of the studies, in medicine and genetics, a genetic or allelic heterogeneous condition is one where the same disease or condition can be caused, or contributed to, by several factors. In the case of genetics, varying different genes or alleles, in cancer research, cancer cell heterogeneity is thought to be one of the underlying reasons that make treatment of cancer difficult. In physics, heterogeneous is understood to mean having physical properties that vary within the medium, in sociology, heterogeneous may refer to a society or group that includes individuals of differing ethnicities, cultural backgrounds, sexes, or ages. Academic Press Dictionary of Science and Technology
5.
Middleware
–
Middleware is computer software that provides services to software applications beyond those available from the operating system. It can be described as software glue, middleware makes it easier for software developers to implement communication and input/output, so they can focus on the specific purpose of their application. The term is most commonly used for software that enables communication, an IETF workshop in 2000 defined middleware as those services found above the transport layer set of services but below the application environment. In this more specific sense middleware can be described as the dash in client-server, middleware includes web servers, application servers, content management systems, and similar tools that support application development and delivery. ObjectWeb defines middleware as, The software layer that lies between the system and applications on each side of a distributed computing system in a network. Services that can be regarded as middleware include enterprise application integration, data integration, message oriented middleware, object request brokers, database access services are often characterised as middleware. Some of them are language specific implementations and support heterogeneous features, examples of database-oriented middleware include ODBC, JDBC and transaction processing monitors. Distributed computing system middleware can loosely be divided into two categories—those that provide services and those that perform in machine-time. This latter middleware is somewhat standardized through the Service Availability Forum and is used in complex, embedded systems within telecom, defense. The term middleware is used in contexts as well. Middleware is sometimes used in a sense to a software driver. The mer software distribution is a middleware, it lacks the Linux kernel, mer is targeted at hardware vendors mobile-oriented operating systems. The Android operating system uses the Linux kernel at its core, in addition, Android provides a middleware layer including libraries that provide services such as data storage, screen display, multimedia, and web browsing. Because the middleware libraries are compiled to machine language, services execute quickly, middleware libraries also implement device-specific functions, so applications and the application framework need not concern themselves with variations between various Android devices. Androids middleware layer also contains the Dalvik virtual machine and its core Java application libraries, game engine software such as Gamebryo and Renderware are sometimes described as middleware, because they provide many services to simplify game development. In simulation technology, middleware is used in the context of the high level architecture that applies to many distributed simulations. It is a layer of software that lies between the code and the run-time infrastructure. Wireless networking developers can use middleware to meet the associated with a wireless sensor network
6.
Loose coupling
–
In computing and systems design a loosely coupled system is one in which each of its components has, or makes use of, little or no knowledge of the definitions of other separate components. Subareas include the coupling of classes, interfaces, data, loose coupling is the opposite of tight coupling. Components in a coupled system can be replaced with alternative implementations that provide the same services. Components in a coupled system are less constrained to the same platform, language, operating system. If systems are decoupled in time, it is difficult to also provide transactional integrity, data replication across different systems provides loose coupling, but creates issues in maintaining consistency. Loose coupling in broader distributed system design is achieved by the use of transactions, queues provided by message-oriented middleware, four types of autonomy, which promote loose coupling, are, reference autonomy, time autonomy, format autonomy, and platform autonomy. Event-driven architecture also aims at promoting loose coupling, loose coupling of interfaces can be enhanced by publishing data in a standard format. Loose coupling between program components can be enhanced by using data types in parameters. Passing customized data types or objects requires both components to have knowledge of the data definition. Loose coupling of services can be enhanced by reducing the information passed into a service to the key data, for example, a service that sends a letter is most reusable when just the customer identifier is passed and the customer address is obtained within the service. This decouples services because services do not need to be called in a specific order Coupling refers to the degree of knowledge that one component has of another. Loose coupling in computing is interpreted as encapsulation vs. non-encapsulation, an example of tight coupling occurs when a dependent class contains a pointer directly to a concrete class which provides the required behavior. The dependency cannot be substituted, or its signature changed, without requiring a change to the dependent class, loose coupling occurs when the dependent class contains a pointer only to an interface, which can then be implemented by one or many concrete classes. The dependent classs dependency is to a contract specified by the interface, any class that implements the interface can thus satisfy the dependency of a dependent class without having to change the class. Strong coupling does not allow this, functional languages have patterns of Continuations, Closure, or generators. See Clojure and Lisp as examples of programming languages. Object-oriented languages like Smalltalk and Ruby have code blocks, whereas Eiffel has agents, the basic idea is to objectify a function independent of any other enclosing concept. See First-class function for further insight into functions as objects, which qualifies as one form of first-class function
7.
Parallel computing
–
Parallel computing is a type of computation in which many calculations or the execution of processes are carried out simultaneously. Large problems can often be divided into smaller ones, which can then be solved at the same time, there are several different forms of parallel computing, bit-level, instruction-level, data, and task parallelism. Parallelism has been employed for years, mainly in high-performance computing. As power consumption by computers has become a concern in recent years, parallel computing has become the dominant paradigm in computer architecture, specialized parallel computer architectures are sometimes used alongside traditional processors, for accelerating specific tasks. Communication and synchronization between the different subtasks are typically some of the greatest obstacles to getting good parallel program performance, a theoretical upper bound on the speed-up of a single program as a result of parallelization is given by Amdahls law. Traditionally, computer software has been written for serial computation, to solve a problem, an algorithm is constructed and implemented as a serial stream of instructions. These instructions are executed on a central processing unit on one computer, only one instruction may execute at a time—after that instruction is finished, the next one is executed. Parallel computing, on the hand, uses multiple processing elements simultaneously to solve a problem. This is accomplished by breaking the problem into independent parts so that each processing element can execute its part of the algorithm simultaneously with the others. The processing elements can be diverse and include such as a single computer with multiple processors, several networked computers, specialized hardware. Frequency scaling was the dominant reason for improvements in performance from the mid-1980s until 2004. The runtime of a program is equal to the number of instructions multiplied by the time per instruction. Maintaining everything else constant, increasing the frequency decreases the average time it takes to execute an instruction. An increase in frequency thus decreases runtime for all compute-bound programs. However, power consumption P by a chip is given by the equation P = C × V2 × F, where C is the capacitance being switched per clock cycle, V is voltage, increases in frequency increase the amount of power used in a processor. Moores law is the observation that the number of transistors in a microprocessor doubles every 18 to 24 months. Despite power consumption issues, and repeated predictions of its end, with the end of frequency scaling, these additional transistors can be used to add extra hardware for parallel computing. Optimally, the speedup from parallelization would be linear—doubling the number of processing elements should halve the runtime, however, very few parallel algorithms achieve optimal speedup
8.
Computer network
–
A computer network or data network is a telecommunications network which allows nodes to share resources. In computer networks, networked computing devices exchange data with other using a data link. The connections between nodes are established using either cable media or wireless media, the best-known computer network is the Internet. Network computer devices that originate, route and terminate the data are called network nodes, nodes can include hosts such as personal computers, phones, servers as well as networking hardware. Two such devices can be said to be networked together when one device is able to exchange information with the other device, Computer networks differ in the transmission medium used to carry their signals, communications protocols to organize network traffic, the networks size, topology and organizational intent. In most cases, application-specific communications protocols are layered over other more general communications protocols and this formidable collection of information technology requires skilled network management to keep it all running reliably. The chronology of significant computer-network developments includes, In the late 1950s, in 1960, the commercial airline reservation system semi-automatic business research environment went online with two connected mainframes. Licklider developed a group he called the Intergalactic Computer Network. In 1964, researchers at Dartmouth College developed the Dartmouth Time Sharing System for distributed users of computer systems. The same year, at Massachusetts Institute of Technology, a group supported by General Electric and Bell Labs used a computer to route. Throughout the 1960s, Leonard Kleinrock, Paul Baran, and Donald Davies independently developed network systems that used packets to transfer information between computers over a network, in 1965, Thomas Marill and Lawrence G. Roberts created the first wide area network. This was an precursor to the ARPANET, of which Roberts became program manager. Also in 1965, Western Electric introduced the first widely used telephone switch that implemented true computer control, in 1972, commercial services using X.25 were deployed, and later used as an underlying infrastructure for expanding TCP/IP networks. In July 1976, Robert Metcalfe and David Boggs published their paper Ethernet, Distributed Packet Switching for Local Computer Networks, in 1979, Robert Metcalfe pursued making Ethernet an open standard. In 1976, John Murphy of Datapoint Corporation created ARCNET, a network first used to share storage devices. In 1995, the transmission speed capacity for Ethernet increased from 10 Mbit/s to 100 Mbit/s, by 1998, Ethernet supported transmission speeds of a Gigabit. Subsequently, higher speeds of up to 100 Gbit/s were added, the ability of Ethernet to scale easily is a contributing factor to its continued use. Providing access to information on shared storage devices is an important feature of many networks, a network allows sharing of files, data, and other types of information giving authorized users the ability to access information stored on other computers on the network
9.
Network interface controller
–
A network interface controller is a computer hardware component that connects a computer to a computer network. Early network interface controllers were commonly implemented on expansion cards that plugged into a computer bus, the low cost and ubiquity of the Ethernet standard means that most newer computers have a network interface built into the motherboard. The network controller implements the electronic circuitry required to communicate using a physical layer and data link layer standard such as Ethernet, Fibre Channel. The NIC allows computers to communicate over a network, either by using cables or wirelessly. Although other network technologies exist, IEEE802 networks including the Ethernet variants have achieved near-ubiquity since the mid-1990s, newer server motherboards may even have dual network interfaces built-in. The Ethernet capabilities are integrated into the motherboard chipset or implemented via a low-cost dedicated Ethernet chip. A separate network card is not required unless additional interfaces are needed or some type of network is used. The NIC may use one or more of the techniques to indicate the availability of packets to transfer. Interrupt-driven I/O is where the peripheral alerts the CPU that it is ready to transfer data, also, NICs may use one or more of the following techniques to transfer packet data, Programmed input/output is where the CPU moves the data to or from the NIC to memory. Direct memory access is where some other device other than the CPU assumes control of the bus to move data to or from the NIC to memory. This removes load from the CPU but requires more logic on the card, in addition, a packet buffer on the NIC may not be required and latency can be reduced. There are two types of DMA, third-party DMA in which a DMA controller other than the NIC performs transfers, an Ethernet network controller typically has an 8P8C socket where the network cable is connected. Older NICs also supplied BNC, or AUI connections, a few LEDs inform the user of whether the network is active, and whether or not data transmission occurs. Ethernet network controllers typically support 10 Mbit/s Ethernet,100 Mbit/s Ethernet, such controllers are designated as 10/100/1000, meaning that they can support a notional maximum transfer rate of 10,100 or 1000 Mbit/s. 10 Gigabit Ethernet NICs are also available, and, as of November 2014, are beginning to be available on computer motherboards, multiqueue NICs provide multiple transmit and receive queues, allowing packets received by the NIC to be assigned to one of its receive queues. The hardware-based distribution of the interrupts, described above, is referred to as receive-side scaling, purely software implementations also exist, such as the receive packet steering and receive flow steering. Examples of such implementations are the RFS and Intel Flow Director, with multiqueue NICs, additional performance improvements can be achieved by distributing outgoing traffic among different transmit queues. By assigning different transmit queues to different CPUs/cores, various operating systems internal contentions can be avoided and those NICs support, Accessing local and remote memory without involving the remote CPU
10.
Ethernet
–
Ethernet /ˈiːθərnɛt/ is a family of computer networking technologies commonly used in local area networks, metropolitan area networks and wide area networks. It was commercially introduced in 1980 and first standardized in 1983 as IEEE802.3, over time, Ethernet has largely replaced competing wired LAN technologies such as token ring, FDDI and ARCNET. The original 10BASE5 Ethernet uses coaxial cable as a medium, while the newer Ethernet variants use twisted pair. Over the course of its history, Ethernet data transfer rates have increased from the original 2.94 megabits per second to the latest 100 gigabits per second. The Ethernet standards comprise several wiring and signaling variants of the OSI physical layer in use with Ethernet, systems communicating over Ethernet divide a stream of data into shorter pieces called frames. As per the OSI model, Ethernet provides services up to, since its commercial release, Ethernet has retained a good degree of backward compatibility. Features such as the 48-bit MAC address and Ethernet frame format have influenced other networking protocols, the primary alternative for some uses of contemporary LANs is Wi-Fi, a wireless protocol standardized as IEEE802.11. Ethernet was developed at Xerox PARC between 1973 and 1974 and it was inspired by ALOHAnet, which Robert Metcalfe had studied as part of his PhD dissertation. In 1975, Xerox filed a patent application listing Metcalfe, David Boggs, Chuck Thacker, in 1976, after the system was deployed at PARC, Metcalfe and Boggs published a seminal paper. Metcalfe left Xerox in June 1979 to form 3Com and he convinced Digital Equipment Corporation, Intel, and Xerox to work together to promote Ethernet as a standard. The so-called DIX standard, for Digital/Intel/Xerox, specified 10 Mbit/s Ethernet, with 48-bit destination and source addresses and it was published on September 30,1980 as The Ethernet, A Local Area Network. Data Link Layer and Physical Layer Specifications, version 2 was published in November,1982 and defines what has become known as Ethernet II. Formal standardization efforts proceeded at the time and resulted in the publication of IEEE802.3 on June 23,1983. Ethernet initially competed with two largely proprietary systems, Token Ring and Token Bus, in the process, 3Com became a major company. 3Com shipped its first 10 Mbit/s Ethernet 3C100 NIC in March 1981, an Ethernet adapter card for the IBM PC was released in 1982, and, by 1985, 3Com had sold 100,000. Parallel port based Ethernet adapters were produced for a time, with drivers for DOS, by the early 1990s, Ethernet became so prevalent that it was a must-have feature for modern computers, and Ethernet ports began to appear on some PCs and most workstations. This process was sped up with the introduction of 10BASE-T and its relatively small modular connector. Since then, Ethernet technology has evolved to meet new bandwidth, in addition to computers, Ethernet is now used to interconnect appliances and other personal devices
11.
Supercomputer
–
A supercomputer is a computer with a high level of computing performance compared to a general-purpose computer. Performance of a supercomputer is measured in floating-point operations per second instead of instructions per second. As of 2015, there are supercomputers which can perform up to quadrillions of FLOPS and it tops the rankings in the TOP500 supercomputer list. Sunway TaihuLights emergence is also notable for its use of indigenous chips, as of June 2016, China, for the first time, had more computers on the TOP500 list than the United States. However, U. S. built computers held ten of the top 20 positions, in November 2016 the U. S. has five of the top 10, throughout their history, they have been essential in the field of cryptanalysis. The use of multi-core processors combined with centralization is an emerging trend, the history of supercomputing goes back to the 1960s, with the Atlas at the University of Manchester and a series of computers at Control Data Corporation, designed by Seymour Cray. These used innovative designs and parallelism to achieve superior computational peak performance, Cray left CDC in 1972 to form his own company, Cray Research. Four years after leaving CDC, Cray delivered the 80 MHz Cray 1 in 1976, the Cray-2 released in 1985 was an 8 processor liquid cooled computer and Fluorinert was pumped through it as it operated. It performed at 1.9 gigaflops and was the second fastest after M-13 supercomputer in Moscow. Fujitsus Numerical Wind Tunnel supercomputer used 166 vector processors to gain the top spot in 1994 with a speed of 1.7 gigaFLOPS per processor. The Hitachi SR2201 obtained a performance of 600 GFLOPS in 1996 by using 2048 processors connected via a fast three-dimensional crossbar network. The Intel Paragon could have 1000 to 4000 Intel i860 processors in various configurations, the Paragon was a MIMD machine which connected processors via a high speed two dimensional mesh, allowing processes to execute on separate nodes, communicating via the Message Passing Interface. Approaches to supercomputer architecture have taken dramatic turns since the earliest systems were introduced in the 1960s, early supercomputer architectures pioneered by Seymour Cray relied on compact innovative designs and local parallelism to achieve superior computational peak performance. However, in time the demand for increased computational power ushered in the age of massively parallel systems, supercomputers of the 21st century can use over 100,000 processors connected by fast connections. The Connection Machine CM-5 supercomputer is a parallel processing computer capable of many billions of arithmetic operations per second. Throughout the decades, the management of heat density has remained a key issue for most centralized supercomputers, the large amount of heat generated by a system may also have other effects, e. g. reducing the lifetime of other system components. There have been diverse approaches to management, from pumping Fluorinert through the system. Systems with a number of processors generally take one of two paths
12.
Bus (computing)
–
In computer architecture, a bus is a communication system that transfers data between components inside a computer, or between computers. This expression covers all related components and software, including communication protocols. Modern computer buses can use both parallel and bit serial connections, and can be wired in either a multidrop or daisy chain topology, or connected by switched hubs, as in the case of USB. An early computer might contain a hand-wired CPU of vacuum tubes, a drum for main memory. In both examples, computer buses of one form or another move data between all of these devices, in most traditional computer architectures, the CPU and main memory tend to be tightly coupled. In most cases, the CPU and memory share signalling characteristics, the bus connecting the CPU and memory is one of the defining characteristics of the system, and often referred to simply as the system bus. It is possible to allow peripherals to communicate with memory in the same fashion and this is commonly accomplished through some sort of standardized electrical connector, several of these forming the expansion bus or local bus. However, as the differences between the CPU and peripherals varies widely, some solution is generally needed to ensure that peripherals do not slow overall system performance. Many CPUs feature a set of pins similar to those for communicating with memory. Others use smart controllers to place the data directly in memory, most modern systems combine both solutions, where appropriate. As the number of potential peripherals grew, using a card for every peripheral became increasingly untenable. This has led to the introduction of bus systems designed specifically to support multiple peripherals, common examples are the SATA ports in modern computers, which allow a number of hard drives to be connected without the need for a card. However, these systems are generally too expensive to implement in low-end devices. This has led to the development of a number of low-performance bus systems for these solutions. All such examples may be referred to as peripheral buses, although this terminology is not universal, in modern systems the performance difference between the CPU and main memory has grown so great that increasing amounts of high-speed memory is built directly into the CPU, known as a cache. These system buses are used to communicate with most other peripherals, through adaptors. Such systems are more similar to multicomputers, communicating over a bus rather than a network. In these cases, expansion buses are entirely separate and no longer share any architecture with their host CPU, what would have formerly been a system bus is now often known as a front-side bus
13.
Drug discovery
–
In the fields of medicine, biotechnology and pharmacology, drug discovery is the process by which new candidate medications are discovered. Historically, drugs were discovered through identifying the active ingredient from traditional remedies or by serendipitous discovery, hits from these screens are then tested in cells and then in animals for efficacy. Once a compound that fulfills all of these requirements has been identified, one or more of these steps may, but not necessarily, involve computer-aided drug design. Modern drug discovery is usually a capital-intensive process that involves large investments by pharmaceutical industry corporations as well as national governments. Despite advances in technology and understanding of systems, drug discovery is still a lengthy, expensive, difficult. In 2010, the research and development cost of new molecular entity was about US$1.8 billion. Drug discovery is done by companies, with research assistance from universities. The final product of drug discovery is a patent on the potential drug, the drug requires very expensive Phase I, II and III clinical trials, and most of them fail. Small companies have a role, often then selling the rights to larger companies that have the resources to run the clinical trials. This made for the beginning of the era in pharmacology, as pure chemicals, instead of crude extracts. Examples of drug compounds isolated from crude preparations are morphine, the agent in opium, and digoxin. Organic chemistry also led to the synthesis of many of the natural products isolated from biological sources, historically substances, whether crude extracts or purified chemicals were screened for biological activity without knowledge of the biological target. Only after a substance was identified was an effort made to identify the target. This approach is known as classical pharmacology, forward pharmacology, or phenotypic drug discovery, later, small molecules were synthesized to specifically target a known physiological/pathological pathway, rather than adopt the mass screening of banks of stored compounds. Cloning of human proteins made possible the screening of large libraries of compounds against specific targets thought to be linked to specific diseases and this approach is known as reverse pharmacology and is the most frequently used approach today. The definition of target itself is something argued within the pharmaceutical industry, generally, the target is the naturally existing cellular or molecular structure involved in the pathology of interest that the drug-in-development is meant to act on. However, the distinction between a new and established target can be made without an understanding of just what a target is. This distinction is made by pharmaceutical companies engaged in discovery
14.
Seismic analysis
–
Seismic analysis is a subset of structural analysis and is the calculation of the response of a building structure to earthquakes. It is part of the process of design, earthquake engineering or structural assessment. As seen in the figure, a building has the potential to ‘wave’ back and this is called the ‘fundamental mode’, and is the lowest frequency of building response. Most buildings, however, have higher modes of response, which are activated during earthquakes. The figure just shows the second mode, but there are higher ‘shimmy’ modes, nevertheless, the first and second modes tend to cause the most damage in most cases. The earliest provisions for seismic resistance were the requirement to design for a force equal to a proportion of the building weight. This approach was adopted in the appendix of the 1927 Uniform Building Code and it later became clear that the dynamic properties of the structure affected the loads generated during an earthquake. In the Los Angeles County Building Code of 1943 a provision to vary the load based on the number of levels was adopted. The University of California, Berkeley was a base for computer-based seismic analysis of structures. Students included Ed Wilson, who went on to write the program SAP in 1970, very large and complex buildings can be modeled in this way. Structural analysis methods can be divided into the five categories. This approach defines a series of acting on a building to represent the effect of earthquake ground motion. It assumes that the building responds in its fundamental mode, for this to be true, the building must be low-rise and must not twist significantly when the ground moves. The response is read from a response spectrum, given the natural frequency of the building. The applicability of this method is extended in many building codes by applying factors to account for higher buildings with some higher modes, to account for effects due to yielding of the structure, many codes apply modification factors that reduce the design forces. This approach permits the multiple modes of response of a building to be taken into account and this is required in many building codes for all except very simple or very complex structures. The response of a structure can be defined as a combination of special shapes that in a vibrating string correspond to the harmonics. Computer analysis can be used to determine these modes for a structure
15.
Back office
–
A back office in most corporations is where tasks dedicated to running the company itself take place. Although the operations of an office are seldom prominent, they are a major contributor to a business. Broadly speaking, back office includes roles that affect the left side of business trading statement, back offices may be located somewhere other than company headquarters. Many are in areas and countries with cheaper rent and lower labor costs, some office parks provide back offices for tenants whose front offices are in more expensive neighborhoods. Back office functions can be outsourced to consultants and contractors, including ones in other countries, examples of back-office tasks include IT departments that keep the phones and computers running, accounting, and human resources. These tasks are supported by back-office systems, secure e-commerce software that processes company information. A back-office system will keep a record of the sales and purchase transactions. Invoices, receipts, and reports can also be produced by the back-office system, maintaining your web content and technology. Management Information Systems for the Information Age Toronto, McGraw-Hill MSN Encarta Dictionary
16.
E-commerce
–
E-commerce is a transaction of buying or selling online. Modern electronic commerce typically uses the World Wide Web for at least one part of the life cycle although it may also use other technologies such as e-mail. 1979, Michael Aldrich demonstrates the first online shopping system,1981, Thomson Holidays UK is the first business-to-business online shopping system to be installed. 1982, Minitel was introduced nationwide in France by France Télécom,1983, California State Assembly holds first hearing on electronic commerce in Volcano, California. Testifying are CPUC, MCI Mail, Prodigy, CompuServe, Volcano Telephone and it is the first comprehensive electronic commerce service. 1989, In May 1989, Sequoia Data Corp, introduced Compumarket The first internet based system for e-commerce. Sellers and buyers could post items for sale and buyers could search the database,1990, Tim Berners-Lee writes the first web browser, WorldWideWeb, using a NeXT computer. 1992, Book Stacks Unlimited in Cleveland opens a sales website selling books online with credit card processing. 1993, Paget Press releases edition No.3 of the first app store, The Electronic AppWrapper 1994, Netscape 1.0 is introduced in late 1994 with SSL encryption that made transactions secure. 1994, Ipswitch IMail Server becomes the first software available online for sale,1994, Ten Summoners Tales by Sting becomes the first secure online purchase through NetMarket. 1995, The US National Science Foundation lifts its former strict prohibition of commercial enterprise on the Internet, the shopping service at launch featured W H Smith, Tesco, Virgin Megastores/Our Price, Great Universal Stores, Interflora, Dixons Retail, Past Times, PC World and Innovations. 1995, Jeff Bezos launches Amazon. com and the first commercial-free 24-hour, internet-only radio stations, Radio HK, eBay is founded by computer programmer Pierre Omidyar as AuctionWeb. 1996, IndiaMART B2B marketplace established in India,1996, ECPlaza B2B marketplace established in Korea. 1996, The use of Excalibur BBS with replicated Storefronts was an implementation of electronic commerce started by a group of SysOps in Australia. 1998, Electronic postal stamps can be purchased and downloaded for printing from the Web,1999, Alibaba Group is established in China. Business. com sold for US $7.5 million to eCompanies, the peer-to-peer filesharing software Napster launches. ATG Stores launches to sell items for the home online. 2000, Complete Idiots Guide to E-commerce released on Amazon 2000,2001, Alibaba. com achieved profitability in December 2001
17.
Web service
–
A web service is a service offered by an electronic device to another electronic device, communicating with each other via the World Wide Web. Another common application offered to the end user may be a mashup, where a web server consumes several web services at different machines, the W3C defines a web service generally as, A web service is a software system designed to support interoperable machine-to-machine interaction over a network. Web services may use SOAP over HTTP protocol, allowing less costly interactions over the Internet than via proprietary solutions like EDI/B2B, besides SOAP over HTTP, web services can also be implemented on other reliable transport mechanisms like FTP. In a 2002 document, the W3C Web Services Architecture Working Group defined a Web Services Architecture, in this, It has an interface described in a machine-processable format. The term web service describes a way of integrating web-based applications using the XML, SOAP, WSDL. A web service is a method of communication between two electronic devices over a network and it is a software function provided at a network address over the web with the service always on as in the concept of utility computing. Many organizations use multiple systems for management. Different software systems often need to exchange data with other. The software system that requests data is called a service requester, whereas the system that would process the request. Different software may use different programming languages, and hence there is a need for a method of exchange that doesnt depend upon a particular programming language. Most types of software can, however, interpret XML tags, thus, web services can use XML files for data exchange. Rules for communication between different systems need to be defined, such as, How one system can request data from another system, which specific parameters are needed in the data request. What would be the structure of the data produced, what error messages to display when a certain rule for communication is not observed, to make troubleshooting easier. All of these rules for communication are defined in a file called WSDL, a directory called UDDI defines which software system should be contacted for which type of data. So when one software system needs one particular report/data, it would go to the UDDI, once the software system finds out which other system it should contact, it would then contact that system using a special protocol called SOAP. The service provider system would first validate the data request by referring to the WSDL file, a Web API is a development in web services where emphasis has been moving to simpler representational state transfer based communications. RESTful APIs do not require XML-based web service protocols to support their interfaces, Automated tools can aid in the creation of a web service. For services using WSDL, it is possible to automatically generate WSDL for existing classes or to generate a class skeleton given existing WSDL
18.
Internet
–
The Internet is the global system of interconnected computer networks that use the Internet protocol suite to link devices worldwide. The origins of the Internet date back to research commissioned by the United States federal government in the 1960s to build robust, the primary precursor network, the ARPANET, initially served as a backbone for interconnection of regional academic and military networks in the 1980s. Although the Internet was widely used by academia since the 1980s, Internet use grew rapidly in the West from the mid-1990s and from the late 1990s in the developing world. In the two decades since then, Internet use has grown 100-times, measured for the period of one year, newspaper, book, and other print publishing are adapting to website technology, or are reshaped into blogging, web feeds and online news aggregators. The entertainment industry was initially the fastest growing segment on the Internet, the Internet has enabled and accelerated new forms of personal interactions through instant messaging, Internet forums, and social networking. Business-to-business and financial services on the Internet affect supply chains across entire industries, the Internet has no centralized governance in either technological implementation or policies for access and usage, each constituent network sets its own policies. The term Internet, when used to refer to the global system of interconnected Internet Protocol networks, is a proper noun. In common use and the media, it is not capitalized. Some guides specify that the word should be capitalized when used as a noun, the Internet is also often referred to as the Net, as a short form of network. Historically, as early as 1849, the word internetted was used uncapitalized as an adjective, the designers of early computer networks used internet both as a noun and as a verb in shorthand form of internetwork or internetworking, meaning interconnecting computer networks. The terms Internet and World Wide Web are often used interchangeably in everyday speech, however, the World Wide Web or the Web is only one of a large number of Internet services. The Web is a collection of interconnected documents and other web resources, linked by hyperlinks, the term Interweb is a portmanteau of Internet and World Wide Web typically used sarcastically to parody a technically unsavvy user. The ARPANET project led to the development of protocols for internetworking, the third site was the Culler-Fried Interactive Mathematics Center at the University of California, Santa Barbara, followed by the University of Utah Graphics Department. In an early sign of growth, fifteen sites were connected to the young ARPANET by the end of 1971. These early years were documented in the 1972 film Computer Networks, early international collaborations on the ARPANET were rare. European developers were concerned with developing the X.25 networks, in December 1974, RFC675, by Vinton Cerf, Yogen Dalal, and Carl Sunshine, used the term internet as a shorthand for internetworking and later RFCs repeated this use. Access to the ARPANET was expanded in 1981 when the National Science Foundation funded the Computer Science Network, in 1982, the Internet Protocol Suite was standardized, which permitted worldwide proliferation of interconnected networks.5 Mbit/s and 45 Mbit/s. Commercial Internet service providers emerged in the late 1980s and early 1990s, the ARPANET was decommissioned in 1990
19.
Node (computer science)
–
A node is a basic unit used in computer science. Nodes are devices or data points on a larger network, devices such as a personal computer, cell phone, or printer are nodes. When defining nodes on the internet, a node is anything that has an IP address, nodes are individual parts of a larger data structure, such as linked lists and tree data structures. Nodes contain data and also may link to other nodes, links between nodes are often implemented by pointers. Nodes are often arranged into tree structures, a node represents the information contained in a single structure. These nodes may contain a value or condition, or possibly serve as another independent data structure, nodes are represented by a single parent node. The highest point on a structure is called a root node, which does not have a parent node. The height of a node is determined by the longest path from node to the furthest leaf node. Node depth is determined by the distance between that node and the root node. The root node is said to have a depth of zero, data can be discovered along these network paths. An IP address uses this kind of system of nodes to define its location in a network, child, A child node is a node extending from another node. For example, a computer with internet access could be considered a child node of a representing the internet. The inverse relationship is that of a parent node, if node C is a child of node A, then A is the parent node of C. Degree, the degree of a node is the number of children of the node, depth, the depth of node A is the length of the path from A to the root node. The root node is said to have depth 0, height, the height of node A is the length of the longest path through children to a leaf node. Internal node, a node with at least one child, leaf node, a node with no children. Root node, a node distinguished from the rest of the tree nodes, usually, it is depicted as the highest node of the tree. Sibling nodes, these are connected to the same parent node
20.
Concurrency (computer science)
–
In computer science, concurrency is the decomposability property of a program, algorithm, or problem into order-independent or partially-ordered components or units. This means that if the concurrent units of the program, algorithm, or problem are executed out-of-order or in partial order. This allows for execution of the concurrent units, which can significantly improve overall speed of the execution in multi-processor. The ensuing decades have seen a growth of interest in concurrency—particularly in distributed systems. Looking back at the origins of the field, what stands out is the role played by Edsger Dijkstra. Concurrent use of shared resources can be a source of indeterminacy leading to such as deadlocks. Concurrency theory has been a field of research in theoretical computer science. One of the first proposals was Carl Adam Petris seminal work on Petri Nets in the early 1960s, in the years since, a wide variety of formalisms have been developed for modeling and reasoning about concurrency. g. Some of these are based on passing, while others have different mechanisms for concurrency. The proliferation of different models of concurrency has motivated some researchers to develop ways to unify these different theoretical models, various types of temporal logic can be used to help reason about concurrent systems. Some of these logics, such as linear temporal logic and computational tree logic, others, such as action computational tree logic, Hennessy-Milner logic, and Lamports temporal logic of actions, build their assertions from sequences of actions. The principal application of these logics is in writing specifications for concurrent systems, concurrent programming encompasses programming languages and algorithms used to implement concurrent systems. The base goals of concurrent programming include correctness, performance and robustness, concurrent systems such as Operating systems and Database management systems are generally designed to operate indefinitely, including automatic recovery from failure, and not terminate unexpectedly. Because they use shared resources, concurrent systems in general require the inclusion of some kind of arbiter somewhere in their implementation, the use of arbiters introduces the possibility of indeterminacy in concurrent computation which has major implications for practice including correctness and performance. Some concurrent programming models include coprocesses and deterministic concurrency, in these models, threads of control explicitly yield their timeslices, either to the system or to another process. Tanenbaum, Andrew S. Van Steen, Maarten, a Practical Theory of Reactive Systems. Concurrency, State Models and Java Programming, concurrent Systems at The WWW Virtual Library Concurrency patterns presentation given at scaleconf
21.
Computer memory
–
In computing, memory refers to the computer hardware devices involved to store information for immediate use in a computer, it is synonymous with the term primary storage. Computer memory operates at a speed, for example random-access memory, as a distinction from storage that provides slow-to-access program and data storage. If needed, contents of the memory can be transferred to secondary storage. An archaic synonym for memory is store, there are two main kinds of semiconductor memory, volatile and non-volatile. Examples of non-volatile memory are flash memory and ROM, PROM, EPROM and EEPROM memory, most semiconductor memory is organized into memory cells or bistable flip-flops, each storing one bit. Flash memory organization includes both one bit per cell and multiple bits per cell. The memory cells are grouped into words of fixed word length, each word can be accessed by a binary address of N bit, making it possible to store 2 raised by N words in the memory. This implies that processor registers normally are not considered as memory, since they only store one word, typical secondary storage devices are hard disk drives and solid-state drives. In the early 1940s, memory technology oftenly permit a capacity of a few bytes, the next significant advance in computer memory came with acoustic delay line memory, developed by J. Presper Eckert in the early 1940s. Delay line memory would be limited to a capacity of up to a few hundred thousand bits to remain efficient, two alternatives to the delay line, the Williams tube and Selectron tube, originated in 1946, both using electron beams in glass tubes as means of storage. Using cathode ray tubes, Fred Williams would invent the Williams tube, the Williams tube would prove more capacious than the Selectron tube and less expensive. The Williams tube would prove to be frustratingly sensitive to environmental disturbances. Efforts began in the late 1940s to find non-volatile memory, jay Forrester, Jan A. Rajchman and An Wang developed magnetic core memory, which allowed for recall of memory after power loss. Magnetic core memory would become the dominant form of memory until the development of transistor-based memory in the late 1960s, developments in technology and economies of scale have made possible so-called Very Large Memory computers. The term memory when used with reference to computers generally refers to Random Access Memory or RAM, volatile memory is computer memory that requires power to maintain the stored information. Most modern semiconductor volatile memory is either static RAM or dynamic RAM, SRAM retains its contents as long as the power is connected and is easy for interfacing, but uses six transistors per bit. SRAM is not worthwhile for desktop system memory, where DRAM dominates, SRAM is commonplace in small embedded systems, which might only need tens of kilobytes or less. Forthcoming volatile memory technologies that aim at replacing or competing with SRAM and DRAM include Z-RAM and A-RAM, non-volatile memory is computer memory that can retain the stored information even when not powered
22.
Dial-up Internet access
–
The users computer or router uses an attached modem to encode and decode information into and from audio frequency signals, respectively. In 1979, Tom Truscott and Steve Bellovin, graduate students for Duke University, the USENET was a UNIX based system that used a dial-up connection to transfer data through telephone modems. Dial-up Internet has been around since the 1980s via public providers such as NSFNET-linked universities and was first offered commercially in July 1992 by Sprint. Despite losing ground to broadband since the late-1990s, dial-up may still be used other forms are not available or the cost is too high. Dial-up connections to the Internet require no other than the telephone network. Dial-up requires time to establish a connection and perform configuration for protocol synchronization before data transfers can take place. In locales with telephone connection charges, each connection incurs an incremental cost, if calls are time-metered, the duration of the connection incurs costs. Dial-up access is a transient connection, because either the user, technically inclined users often find a way to disable the auto-disconnect program such that they can remain connected for more days than one. A2008 Pew research center study stated that only 10 percent of US adults still used dial-up Internet access, the study found that the most common reason for retaining dial-up access was high broadband prices. Users cited lack of infrastructure as a less often than stating that they would never upgrade to broadband. According to the United States Federal Communications Commission, 6% used dial-up in 2010, by 2013, that number had fallen to 3%. Broadband internet access via cable, digital line, satellite. Broadband connections typically offer speeds of 700 kbit/s or higher for more than the price of dial-up on average. In addition broadband connections are always on, thus avoiding the need to connect and disconnect at the start, however, many rural areas still remain without high speed Internet despite the eagerness of potential customers. This can be attributed to population, location, or sometimes ISPs lack of interest due to little chance of profitability and high costs to build the required infrastructure. Some dial-up ISPs have responded to the competition by lowering their rates. Dial-up Internet access has undergone a precipitous fall in usage, in contrast to the year 2000 when about 34% of Internet users used dial-up, this dropped to 3% in 2013. Many newer websites also now assume broadband speeds as the norm, modern dial-up modems typically have a maximum theoretical transfer speed of 56 kbit/s, although in most cases, 40–50 kbit/s is the norm
23.
Operating system
–
An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs, excluding firmware, require a system to function. Operating systems are found on many devices that contain a computer – from cellular phones, the dominant desktop operating system is Microsoft Windows with a market share of around 83. 3%. MacOS by Apple Inc. is in place, and the varieties of Linux is in third position. Linux distributions are dominant in the server and supercomputing sectors, other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can run one program at a time. Multi-tasking may be characterized in preemptive and co-operative types, in preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, e. g. Solaris, Linux, cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking, 32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem, a distributed operating system manages a group of distinct computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing, distributed computations are carried out on more than one machine. When computers in a work in cooperation, they form a distributed system. The technique is used both in virtualization and cloud computing management, and is common in large server warehouses, embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy and they are able to operate with a limited number of resources. They are very compact and extremely efficient by design, Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is a system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could run different programs in succession to speed up processing
24.
Computer architecture
–
In computer engineering, computer architecture is a set of rules and methods that describe the functionality, organization, and implementation of computer systems. Some definitions of architecture define it as describing the capabilities and programming model of a computer, in other definitions computer architecture involves instruction set architecture design, microarchitecture design, logic design, and implementation. The first documented computer architecture was in the correspondence between Charles Babbage and Ada Lovelace, describing the analytical engine, johnson had the opportunity to write a proprietary research communication about the Stretch, an IBM-developed supercomputer for Los Alamos National Laboratory. Brooks went on to develop the IBM System/360 line of computers. Later, computer users came to use the term in many less-explicit ways, the earliest computer architectures were designed on paper and then directly built into the final hardware form. The discipline of architecture has three main subcategories, Instruction Set Architecture, or ISA. The ISA defines the code that a processor reads and acts upon as well as the word size, memory address modes, processor registers. Microarchitecture, or computer organization describes how a processor will implement the ISA. The size of a computers CPU cache for instance, is an issue that generally has nothing to do with the ISA, system Design includes all of the other hardware components within a computing system. These include, Data processing other than the CPU, such as memory access Other issues such as virtualization, multiprocessing. There are other types of computer architecture, E. g. the C, C++, or Java standards define different Programmer Visible Macroarchitecture. UISA —a group of machines with different hardware level microarchitectures may share a common microcode architecture, pin Architecture, The hardware functions that a microprocessor should provide to a hardware platform, e. g. the x86 pins A20M, FERR/IGNNE or FLUSH. Also, messages that the processor should emit so that external caches can be invalidated, pin architecture functions are more flexible than ISA functions because external hardware can adapt to new encodings, or change from a pin to a message. The term architecture fits, because the functions must be provided for compatible systems, the purpose is to design a computer that maximizes performance while keeping power consumption in check, costs low relative to the amount of expected performance, and is also very reliable. For this, many aspects are to be considered which includes Instruction Set Design, Functional Organization, Logic Design, the implementation involves Integrated Circuit Design, Packaging, Power, and Cooling. Optimization of the design requires familiarity with Compilers, Operating Systems to Logic Design, an instruction set architecture is the interface between the computers software and hardware and also can be viewed as the programmers view of the machine. Computers do not understand high level languages such as Java, C++, a processor only understands instructions encoded in some numerical fashion, usually as binary numbers. Software tools, such as compilers, translate those high level languages into instructions that the processor can understand, besides instructions, the ISA defines items in the computer that are available to a program—e. g
25.
Berkeley Open Infrastructure for Network Computing
–
The Berkeley Open Infrastructure for Network Computing, an open-source middleware system, supports volunteer and grid computing. BOINC aims to enable researchers to tap into the enormous processing resources of multiple personal computers around the world, BOINC development originated with a team based at the Space Sciences Laboratory at the University of California, Berkeley and led by David Anderson, who also leads SETI@home. The National Science Foundation funds BOINC through awards SCI/0221529, SCI/0438443, guinness World Records ranks BOINC as the largest computing grid in the world. BOINC code runs on various operating systems, including Microsoft Windows, macOS, Android, Linux, BOINC is free software released under the terms of the GNU Lesser General Public License. BOINC was originally developed to manage the SETI@home project, the original SETI client was a non-BOINC software exclusively for SETI@home. As one of the first volunteer grid computing projects, it was not designed with a level of security. As a result, some participants in the project attempted to cheat the project to gain credits, BOINC was designed, in part, to combat these security breaches. The BOINC project started in February 2002, and the first version was released on April 10,2002, the first BOINC-based project was Predictor@home launched on June 9,2004. In 2009, AQUA@home deployed multi-threaded CPU applications for the first time, as of January 2016,58 BOINC projects are active. In essence, BOINC is software that can use the unused CPU and GPU cycles on a computer to do scientific computing—what one individual does not use of his/her computer, BOINC uses. In late 2008, BOINCs official website announced that NVIDIA had developed a system called CUDA that uses GPUs for scientific computing, with NVIDIAs assistance, some BOINC-based projects now have applications that run on NVIDIA GPUs using CUDA. Beginning in October 2009, BOINC added support for the ATI/AMD family of GPUs also and these applications run from 2× to 10× faster than the former CPU-only versions. In 7. x preview versions, GPU support was added for computers using Mac OS X with AMD Radeon graphic cards, BOINC consists of a server system and client software that communicate with each other to distribute and process work units and return the results. BOINC can be controlled remotely by remote procedure calls, from the command line, BOINC Manager currently has two views, the Advanced View and the Simplified GUI. The Grid View was removed in the 6.6. x clients as it was redundant, the appearance of the Simplified GUI is user-customizable, in that users can create their own designs. A BOINC Account Manager is an application that manages multiple BOINC project accounts across multiple computers, Account managers were designed for people who are new to BOINC or have several computers participating in several projects. The account manager concept was conceived and developed jointly by GridRepublic, GridRepublic Charity Engine Dazzler The BOINC Credit System is designed to avoid cheating by validating results before granting credit. A credit management system helps to ensure users are returning results which are both scientifically and statistically accurate
26.
Virtual organization (grid computing)
–
In grid computing, a virtual organization refers to a dynamic set of individuals or institutions defined around a set of resource-sharing rules and conditions. All these virtual organizations share some commonality among them, including common concerns and requirements, but may vary in size, scope, duration, sociology, a virtual organization has the characteristics of a formal organization while not being one. It comprises a network of smaller organizations which each contribute a part of the production process. Boundaries between organizations are fuzzy, control is generally by market forces, reinforced by the certainty of long- term contracts, the XtreemOS project promised to support virtual organizations. List of distributed computing projects Open Grid Forum Cloud computing
27.
GLite
–
GLite is a middleware computer software project for grid computing used by the CERN LHC experiments and other scientific domains. It was implemented by collaborative efforts of more than 80 people in 12 different academic, gLite provides a framework for building applications tapping into distributed computing and storage resources across the Internet. The gLite services were adopted by more than 250 computing centres and used by more than 15000 researchers in Europe, development of the gLite middleware was then taken over by the European Middleware Initiative, and is now maintained as part of the EMI software stack. The gLite user community is grouped into Virtual Organisations, a user must join a VO supported by the infrastructure running gLite to be authenticated and authorized to using grid resources. The Grid Security Infrastructure in WLCG/EGEE enables secure authentication and communication over an open network, GSI is based on public key encryption, X.509 certificates, and the Secure Sockets Layer communication protocol, with extensions for single sign-on and delegation. To authenticate himself, a user needs to have a digital X.509 certificate issued by a Certification Authority trusted by the running the middleware. The authorisation of a user on a specific Grid resource can be done in two different ways, the first is simpler, and relies on the grid-mapfile mechanism. The second way relies on the Virtual Organisation Membership Service and the LCAS/LCMAPS mechanism, the access point to the gLite Grid is the User Interface. This can be any machine where users have a personal account, from a UI, a user can be authenticated and authorized to use the WLCG/EGEE resources, and can access the functionalities offered by the Information, Workload and Data management systems. A Computing Element, in Grid terminology, is set of computing resources localized at a site. There are two CE implementations in gLite 3.1, the LCG CE, developed by EDG and used in LCG-22, sites can choose what to install, and some of them provide both types. The GG is responsible for accepting jobs and dispatching them for execution on the WNs via the LRMS, in gLite 3.1 supported LRMS types were OpenPBS/PBSPro, Platform LSF, Maui/Torque, BQS and Condor, and Sun Grid Engine. A Storage Element provides uniform access to storage resources. The Storage Element may control simple disk servers, large arrays or tape-based Mass Storage Systems. Most WLCG/EGEE sites provide at least one SE, Storage Elements can support different data access protocols and interfaces. Simply speaking, GSIFTP is the protocol for whole-file transfers, while local, most storage resources are managed by a Storage Resource Manager, a middleware service providing capabilities like transparent file migration from disk to tape, file pinning, space reservation, etc. However, different SEs may support different versions of the SRM protocol, there is a number of SRM implementations in use, with varying capabilities. The Disk Pool Manager is used for fairly small SEs with disk-based storage only, while CASTOR is designed to manage large-scale MSS, with front-end disks, dCache is targeted at both MSS and large-scale disk array storage systems
28.
Sun Microsystems
–
Sun contributed significantly to the evolution of several key computing technologies, among them Unix, RISC processors, thin client computing, and virtualized computing. Sun was founded on February 24,1982, at its height, the Sun headquarters were in Santa Clara, California, on the former west campus of the Agnews Developmental Center. On January 27,2010, Oracle Corporation acquired Sun by for US$7.4 billion, other technologies include the Java platform, MySQL, and NFS. Sun was a proponent of open systems in general and Unix in particular, the initial design for what became Suns first Unix workstation, the Sun-1, was conceived by Andy Bechtolsheim when he was a graduate student at Stanford University in Palo Alto, California. Bechtolsheim originally designed the SUN workstation for the Stanford University Network communications project as a personal CAD workstation and it was designed around the Motorola 68000 processor with an advanced memory management unit to support the Unix operating system with virtual memory support. He built the first ones from spare parts obtained from Stanfords Department of Computer Science, on February 24,1982, Vinod Khosla, Andy Bechtolsheim, and Scott McNealy, all Stanford graduate students, founded Sun Microsystems. Bill Joy of Berkeley, a developer of the Berkeley Software Distribution. The Sun name is derived from the initials of the Stanford University Network, Sun was profitable from its first quarter in July 1982. By 1983 Sun was known for producing 68000-based systems with high-quality graphics that were the only computers other than DECs VAX to run 4. 2BSD and it licensed the computer design to other manufacturers, which typically used it to build Multibus-based systems running Unix from UniSoft. Suns initial public offering was in 1986 under the stock symbol SUNW, the symbol was changed in 2007 to JAVA, Sun stated that the brand awareness associated with its Java platform better represented the companys current strategy. Suns logo, which features four interleaved copies of the sun in the form of a rotationally symmetric ambigram, was designed by professor Vaughan Pratt. The initial version of the logo was orange and had the sides oriented horizontally and vertically, but it was rotated to stand on one corner and re-colored purple. In the dot-com bubble, Sun began making more money. It also began spending more, hiring workers and building itself out. Some of this was because of demand, but much was from web start-up companies anticipating business that would never happen. Sales in Suns important hardware division went into free-fall as customers closed shop, several quarters of steep losses led to executive departures, rounds of layoffs, and other cost cutting. In December 2001, the fell to the 1998, pre-bubble level of about $100. But it kept falling, faster than many other tech companies, a year later it had dipped below $10 but bounced back to $20
29.
IBM
–
International Business Machines Corporation is an American multinational technology company headquartered in Armonk, New York, United States, with operations in over 170 countries. The company originated in 1911 as the Computing-Tabulating-Recording Company and was renamed International Business Machines in 1924, IBM manufactures and markets computer hardware, middleware and software, and offers hosting and consulting services in areas ranging from mainframe computers to nanotechnology. IBM is also a research organization, holding the record for most patents generated by a business for 24 consecutive years. IBM has continually shifted its business mix by exiting commoditizing markets and focusing on higher-value, also in 2014, IBM announced that it would go fabless, continuing to design semiconductors, but offloading manufacturing to GlobalFoundries. Nicknamed Big Blue, IBM is one of 30 companies included in the Dow Jones Industrial Average and one of the worlds largest employers, with nearly 380,000 employees. Known as IBMers, IBM employees have been awarded five Nobel Prizes, six Turing Awards, ten National Medals of Technology, in the 1880s, technologies emerged that would ultimately form the core of what would become International Business Machines. On June 16,1911, their four companies were amalgamated in New York State by Charles Ranlett Flint forming a fifth company, the Computing-Tabulating-Recording Company based in Endicott, New York. The five companies had 1,300 employees and offices and plants in Endicott and Binghamton, New York, Dayton, Ohio, Detroit, Michigan, Washington, D. C. and Toronto. They manufactured machinery for sale and lease, ranging from commercial scales and industrial time recorders, meat and cheese slicers, to tabulators and punched cards. Thomas J. Watson, Sr. fired from the National Cash Register Company by John Henry Patterson, called on Flint and, Watson joined CTR as General Manager then,11 months later, was made President when court cases relating to his time at NCR were resolved. Having learned Pattersons pioneering business practices, Watson proceeded to put the stamp of NCR onto CTRs companies and his favorite slogan, THINK, became a mantra for each companys employees. During Watsons first four years, revenues more than doubled to $9 million, Watson had never liked the clumsy hyphenated title of the CTR and in 1924 chose to replace it with the more expansive title International Business Machines. By 1933 most of the subsidiaries had been merged into one company, in 1937, IBMs tabulating equipment enabled organizations to process unprecedented amounts of data, its clients including the U. S. During the Second World War the company produced small arms for the American war effort, in 1949, Thomas Watson, Sr. created IBM World Trade Corporation, a subsidiary of IBM focused on foreign operations. In 1952, he stepped down after almost 40 years at the company helm, in 1957, the FORTRAN scientific programming language was developed. In 1961, IBM developed the SABRE reservation system for American Airlines, in 1963, IBM employees and computers helped NASA track the orbital flight of the Mercury astronauts. A year later it moved its headquarters from New York City to Armonk. The latter half of the 1960s saw IBM continue its support of space exploration, on April 7,1964, IBM announced the first computer system family, the IBM System/360
30.
Hewlett-Packard
–
The Hewlett-Packard Company or shortened to Hewlett-Packard was an American multinational information technology company headquartered in Palo Alto, California. The company was founded in a garage in Palo Alto by William Bill Redington Hewlett and David Dave Packard. HP was the worlds leading PC manufacturer from 2007 to Q22013 and it specialized in developing and manufacturing computing, data storage, and networking hardware, designing software and delivering services. HP also had services and consulting business around its products and partner products.4 billion in 2008, in November 2009, HP announced the acquisition of 3Com, with the deal closing on April 12,2010. On April 28,2010, HP announced the buyout of Palm, on September 2,2010, HP won its bidding war for 3PAR with a $33 a share offer, which Dell declined to match. On October 6,2014, Hewlett-Packard announced plans to split the PC and printers business from its enterprise products, the split closed on November 1,2015, and resulted in two publicly traded companies, HP Inc. and Hewlett Packard Enterprise. William Redington Hewlett and David Packard graduated with degrees in engineering from Stanford University in 1935. The company originated in a garage in nearby Palo Alto during a fellowship they had with a past professor, Terman was considered a mentor to them in forming Hewlett-Packard. In 1939, Packard and Hewlett established Hewlett-Packard in Packards garage with a capital investment of US$538. Hewlett and Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett, HP incorporated on August 18,1947, and went public on November 6,1957. Of the many projects they worked on, their very first financially successful product was an audio oscillator. This allowed them to sell the Model 200A for $54.40 when competitors were selling less stable oscillators for over $200, the Model 200 series of generators continued until at least 1972 as the 200AB, still tube-based but improved in design through the years. They worked on technology and artillery shell fuses during World War II. Hewlett-Packards HP Associates division, established around 1960, developed semiconductor devices primarily for internal use, instruments and calculators were some of the products using these devices. HP partnered in the 1960s with Sony and the Yokogawa Electric companies in Japan to develop several high-quality products, the products were not a huge success, as there were high costs in building HP-looking products in Japan. HP and Yokogawa formed a joint venture in 1963 to market HP products in Japan, HP bought Yokogawa Electrics share of Hewlett-Packard Japan in 1999. HP spun off a company, Dynac, to specialize in digital equipment. The name was picked so that the HP logo hp could be turned upside down to be a reverse image of the logo dy of the new company
31.
Gartner
–
Gartner, Inc. is an American research and advisory firm providing information technology related insight for IT and other business leaders located across the world. Its headquarters are in Stamford, Connecticut, United States and it was known as Gartner Group, Inc until 2000, when it was then changed to Gartner. Research provided by Gartner targets CIOs, senior IT, marketing, Gartner clients include large corporations, government agencies, technology companies and the investment community. The company consists of Research, Executive Programs, Consulting and Events, founded in 1979, Gartner has over 8,100 employees, including 1,280 in research, located in 85 countries. Gartner uses hype cycles and Magic Quadrants for visualization of its market analysis results, the company was founded in 1979 by Gideon Gartner. The company went public again in 1993, in 2000 the name was simplified to Gartner. Gene Hall has been the CEO of the company since August 2004 and it has also acquired a number of direct competitors, including NewScience in the late 1990s, Meta Group in 2005 and AMR Research and Burton Group in early 2010. In March 2014 Gartner announced that it had acquired the privately held company Software Advice for an undisclosed amount, in July 2015, Gartner acquired Nubera, the business app discovery network that owns properties like GetApp, AppStorm, AppAppeal or CloudWork. Terms of the deal were not disclosed, in September 2015 it acquired the privately held company Capterra. In June 2016 Gartner announced that it had acquired the privately held company SCM World, headquartered in London, on January 5,2017 Gartner announced it had reached an agreement to acquire CEB, Inc. in a cash and stock deal worth about US$2.6 billion. Gartner has had controversy in forecasts. In 2009, Gartner predicted the PC market would experience the sharpest unit decline in history, the Actual Shipment Decline starts the year 2010. and biggest PC market decline in 2016 SoundView Technology Group, formerly Gartner Securities Corp
32.
Instruction cycle
–
An instruction cycle is the basic operational process of a computer. It is the process by which a computer retrieves a program instruction from its memory, determines what actions the instruction dictates and this cycle is repeated continuously by a computers central processing unit, from boot-up to when the computer is shut down. In simpler CPUs the instruction cycle is executed sequentially, each instruction being processed before the one is started. Memory address register Holds the address of a block of memory for reading from or writing to, Memory data register A two-way register that holds data fetched from memory or data waiting to be stored in memory. Instruction register A temporary holding ground for the instruction that has just been fetched from memory, Arithmetic logic unit Performs mathematical and logical operations. At the end of the operation, the PC points to the next instruction that will be read at the next cycle. Decode the instruction, During this cycle the encoded instruction present in the IR is interpreted by the decoder, read the effective address, In case of a memory instruction the execution phase will be in the next clock pulse. If the instruction has an address, the effective address is read from main memory. If the instruction is direct, nothing is done at this clock pulses, if this is an I/O instruction or a Register instruction, the operation is performed at clock Pulse. If the ALU is involved, it sends a signal back to the CU. The result generated by the operation is stored in the main memory, based on the condition of any feedback from the ALU, Program Counter may be updated to a different address from which the next instruction will be fetched. The cycle begins as soon as power is applied to the system, typically this address points to a set of instructions in read-only memory, which begins the process of loading the operating system. Step 1 of the Instruction Cycle is called the Fetch Cycle and this step prepares the CPU for the next cycle. The Control Unit fetches the instructions address from the Memory Unit, step 2 of the instruction Cycle is called the Decode Cycle. The decoding process allows the CPU to determine what instruction is to be performed, the opcode fetched from the memory is decoded for the next steps and moved to the appropriate registers. The decoding is done by the CPUs Control Unit, step 3 is evaluating which operation it is. If this is a Memory operation - in this step the computer checks if its a direct or indirect memory operation, indirect memory instruction - The effective address is being read from the memory. If this is an I/O or Register instruction - the computer checks its kind, step 4 of the Instruction Cycle is the Execute Cycle
33.
Metaphor
–
A metaphor is a figure of speech that refers, for rhetorical effect, to one thing by mentioning another thing. It may provide clarity or identify hidden similarities between two ideas, antithesis, hyperbole, metonymy and simile are all types of metaphor. The Philosophy of Rhetoric by rhetorician I. A. Richards describes a metaphor as having two parts, the tenor and the vehicle, the tenor is the subject to which attributes are ascribed. The vehicle is the object whose attributes are borrowed, other writers employ the general terms ground and figure to denote the tenor and the vehicle. Cognitive linguistics uses the target and source, respectively. Metaphors are most frequently compared with similes, a simile is a specific type of metaphor that uses the words like or as in comparing two objects, whereas what is commonly referred to as a metaphor states that A is B or substitutes B for A. What is usually referred to as a metaphor asserts the two objects in the comparison are identical on the point of comparison, a simile merely asserts a similarity, for this reason a common-type metaphor is generally considered more forceful than a simile. The metaphor category also contains these types, Allegory, An extended metaphor wherein a story illustrates an important attribute of the subject. Antithesis, A rhetorical contrast of ideas by means of parallel arrangements of words, clauses, or sentences Catachresis, A mixed metaphor used by design and accident. Hyperbole, Excessive exaggeration to illustrate a point Metonymy, A figure of speech using the name of one thing in reference to a different thing of which the first is associated, example, in lands belonging to the crown the word crown is metonymy for ruler or monarch. Parable, An extended metaphor narrated as an anecdote illustrating and teaching such as in Aesops fables, pun, Similar to a metaphor, a pun alludes to another term. However, the difference is that a pun is a frivolous allusion between two different things whereas a metaphor is a purposeful allusion between two different things. Metaphor, like other types of analogy, can usefully be distinguished from metonymy as one of two modes of thought. Thus, a metaphor creates new links between otherwise distinct conceptual domains, whereas a metonymy relies on the links within them. A dead metaphor is one in which the sense of an image has become absent. Examples, to grasp a concept and to gather what youve understood use physical action as a metaphor for understanding, the audience does not need to visualize the action, dead metaphors normally go unnoticed. Some people distinguish between a dead metaphor and a cliché, others use dead metaphor to denote both. A mixed metaphor is one that leaps from one identification to a second identification inconsistent with the first, e. g. Checkmate
34.
Electrical grid
–
An electrical grid is an interconnected network for delivering electricity from suppliers to consumers. Power stations may be located near a source, at a dam site, or to take advantage of renewable energy sources. They are usually large to take advantage of the economies of scale. The electric power which is generated is stepped up to a voltage at which it connects to the electric power transmission network. The bulk power transmission network will move the power long distances, sometimes across international boundaries, on arrival at a substation, the power will be stepped down from a transmission level voltage to a distribution level voltage. As it exits the substation, it enters the distribution wiring, finally, upon arrival at the service location, the power is stepped down again from the distribution voltage to the required service voltage. Electrical grids vary in size covering an single building through national grids which cover whole countries. Early electric energy was produced near the device or service requiring that energy, in the 1880s, electricity competed with steam, hydraulics, and especially coal gas. Coal gas was first produced on premises but later evolved into gasification plants that enjoyed economies of scale. In the industrialized world, cities had networks of piped gas, but gas lamps produced poor light, wasted heat, made rooms hot and smoky, and gave off hydrogen and carbon monoxide. In the 1880s electric lighting soon became advantageous compared to gas lighting, Electric utility companies took advantage of economies of scale and moved to centralized power generation, distribution, and system management. With long distance power transmission it became possible to interconnect stations to balance load, merz was appointed head of a Parliamentary Committee and his findings led to the Williamson Report of 1918, which in turn created the Electricity Supply Bill of 1919. The bill was the first step towards an integrated electricity system, the Electricity Act of 1926 led to the setting up of the National Grid. The Central Electricity Board standardized the nations electricity supply and established the first synchronized AC grid and this started operating as a national system, the National Grid, in 1938. In the United States in the 1920s, utilities formed joint-operations to share peak load coverage, no longer were electric utilities built as vertical monopolies, where generation, transmission and distribution were handled by a single company. Now, the three stages could be split among various companies, in an effort to provide accessibility to high voltage transmission. The Energy Policy Act of 2005 allowed incentives and loan guarantees for energy production. In France, electrification began in the 1900s, with 700 communes in 1919, and 36,528 in 1938
35.
Ian Foster
–
Ian T. Foster is a New Zealand-American computer scientist. Foster was educated at Wellington College and the University of Canterbury in New Zealand, in 2006, he was appointed director of the Computation Institute, a joint project between the University of Chicago, and Argonne National Laboratory. CI brings together scientists and discipline leaders to work on projects with computation as a key component. Fosters honors include the Lovelace Medal of the British Computer Society, the Gordon Bell Prize for high-performance computing, fosters research focuses on the acceleration of discovery in a network using distributed computing. With Carl Kesselman and Steve Tuecke, Foster coined the term grid computing, techniques for data-intensive, methods and software developed under his leadership advanced discovery in areas as high energy physics, environmental science, and biomedicine. For example, grid computing was credited by CERN director Rolf-Dieter Heuer as one of the elements essential for the 2012 discovery of the Higgs boson and his research has also resulted in the development of techniques, tools and algorithms for high-performance distributed computing and parallel computing. His Globus Toolkit project encouraged collaborative computing for engineering, business, in March 2004, Foster co-founded Univa Corporation to commercialize the technology
Media related to