1.
Portsmouth, Virginia
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Portsmouth is an independent city located in the U. S. commonwealth of Virginia. As of the 2010 census, the population was 95,535 and it is part of the Hampton Roads metropolitan area. The shipyard upgrades, remodels, and repairs ships of the US Navy and is one of the few facilities in the world with the capability to dry dock an aircraft carrier. Directly opposite Norfolk, the city of Portsmouth also has miles of waterfront land on the Elizabeth River as part of the harbor of Hampton Roads, there is a ferry boat that takes riders back and forth across the water between Downtown Norfolk and Olde Towne Portsmouth. Portsmouth is located on the side of the Elizabeth River directly across from the City of Norfolk. In 1620, the site of Portsmouth was recognized as suitable shipbuilding location by John Wood, a shipbuilder. The surrounding area was settled as a plantation community. Portsmouth was founded by Colonel William Crawford, a member of the Virginia House of Burgesses and it was established as a town in 1752 by an act of the Virginia General Assembly and was named for Portsmouth, England. In 1767, Andrew Sprowle, a shipbuilder, founded the Gosport Shipyard adjacent to Portsmouth, the Gosport Shipyard at Portsmouth was owned by the Commonwealth of Virginia after the American Revolutionary War and was sold to the new United States federal government. In 1855, the Portsmouth and Norfolk area suffered an epidemic of fever which killed 1 of every three citizens. It became an independent city from Norfolk County in 1858, during the American Civil War, in 1861, Virginia joined the Confederate States of America. Fearing that the Confederacy would take control of the shipyard at Portsmouth, the Confederate forces did in fact take over the shipyard, and did so without armed conflict through an elaborate ruse orchestrated by civilian railroad builder William Mahone. The Union forces withdrew to Fort Monroe across Hampton Roads, which was the land in the area which remained under Union control. In early 1862, the Confederate ironclad warship CSS Virginia was rebuilt using the hulk of USS Merrimack. Virginia engaged the Union ironclad USS Monitor in the famous Battle of Hampton Roads during the Union blockade of Hampton Roads, the Confederates burned the shipyard again when they left in May 1862. Following the recapture of Norfolk and Portsmouth by the Union forces, the name of the shipyard was derived from its location in Norfolk County. The Norfolk Naval Shipyard today is located entirely within the city limits of Portsmouth, Portsmouth was the county seat of Norfolk County until 1963 when the new city of Chesapeake was formed in a political consolidation with the city of South Norfolk. Portsmouths other county neighbor, the former Nansemond County, also consolidated with a smaller city, one of the older cities of Hampton Roads, in the early 21st century, Portsmouth was undergoing moderate urban renewal in the downtown
2.
Massachusetts Institute of Technology
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The Massachusetts Institute of Technology is a private research university in Cambridge, Massachusetts, often cited as one of the worlds most prestigious universities. Researchers worked on computers, radar, and inertial guidance during World War II, post-war defense research contributed to the rapid expansion of the faculty and campus under James Killian. The current 168-acre campus opened in 1916 and extends over 1 mile along the bank of the Charles River basin. The Institute is traditionally known for its research and education in the sciences and engineering, and more recently in biology, economics, linguistics. Air Force and 6 Fields Medalists have been affiliated with MIT, the school has a strong entrepreneurial culture, and the aggregated revenues of companies founded by MIT alumni would rank as the eleventh-largest economy in the world. In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a Conservatory of Art and Science, but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, Rogers, a professor from the University of Virginia, wanted to establish an institution to address rapid scientific and technological advances. The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars, two days after the charter was issued, the first battle of the Civil War broke out. After a long delay through the war years, MITs first classes were held in the Mercantile Building in Boston in 1865, in 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst. In 1866, the proceeds from sales went toward new buildings in the Back Bay. MIT was informally called Boston Tech, the institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker. Programs in electrical, chemical, marine, and sanitary engineering were introduced, new buildings were built, the curriculum drifted to a vocational emphasis, with less focus on theoretical science. The fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership, during these Boston Tech years, MIT faculty and alumni rebuffed Harvard University president Charles W. Eliots repeated attempts to merge MIT with Harvard Colleges Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard, in its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding. Eventually the MIT Corporation approved an agreement to merge with Harvard, over the vehement objections of MIT faculty, students. However, a 1917 decision by the Massachusetts Supreme Judicial Court effectively put an end to the merger scheme, the neoclassical New Technology campus was designed by William W. Bosworth and had been funded largely by anonymous donations from a mysterious Mr. Smith, starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of production and processing
3.
Computer science
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Computer science is the study of the theory, experimentation, and engineering that form the basis for the design and use of computers. An alternate, more succinct definition of science is the study of automating algorithmic processes that scale. A computer scientist specializes in the theory of computation and the design of computational systems and its fields can be divided into a variety of theoretical and practical disciplines. Some fields, such as computational complexity theory, are highly abstract, other fields still focus on challenges in implementing computation. Human–computer interaction considers the challenges in making computers and computations useful, usable, the earliest foundations of what would become computer science predate the invention of the modern digital computer. Machines for calculating fixed numerical tasks such as the abacus have existed since antiquity, further, algorithms for performing computations have existed since antiquity, even before the development of sophisticated computing equipment. Wilhelm Schickard designed and constructed the first working mechanical calculator in 1623, in 1673, Gottfried Leibniz demonstrated a digital mechanical calculator, called the Stepped Reckoner. He may be considered the first computer scientist and information theorist, for, among other reasons and he started developing this machine in 1834, and in less than two years, he had sketched out many of the salient features of the modern computer. A crucial step was the adoption of a card system derived from the Jacquard loom making it infinitely programmable. Around 1885, Herman Hollerith invented the tabulator, which used punched cards to process statistical information, when the machine was finished, some hailed it as Babbages dream come true. During the 1940s, as new and more powerful computing machines were developed, as it became clear that computers could be used for more than just mathematical calculations, the field of computer science broadened to study computation in general. Computer science began to be established as an academic discipline in the 1950s. The worlds first computer science program, the Cambridge Diploma in Computer Science. The first computer science program in the United States was formed at Purdue University in 1962. Since practical computers became available, many applications of computing have become distinct areas of study in their own rights and it is the now well-known IBM brand that formed part of the computer science revolution during this time. IBM released the IBM704 and later the IBM709 computers, still, working with the IBM was frustrating if you had misplaced as much as one letter in one instruction, the program would crash, and you would have to start the whole process over again. During the late 1950s, the science discipline was very much in its developmental stages. Time has seen significant improvements in the usability and effectiveness of computing technology, modern society has seen a significant shift in the users of computer technology, from usage only by experts and professionals, to a near-ubiquitous user base
4.
Intel
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Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California that was founded by Gordon Moore and Robert Noyce. It is the worlds largest and highest valued semiconductor chip makers based on revenue, and is the inventor of the x86 series of microprocessors, Intel supplies processors for computer system manufacturers such as Apple, Lenovo, HP, and Dell. Intel Corporation was founded on July 18,1968, by semiconductor pioneers Robert Noyce and Gordon Moore, the companys name was conceived as portmanteau of the words integrated and electronics. The fact that intel is the term for intelligence information made the name appropriate. Intel was a developer of SRAM and DRAM memory chips. Although Intel created the worlds first commercial microprocessor chip in 1971, during the 1990s, Intel invested heavily in new microprocessor designs fostering the rapid growth of the computer industry. The Open Source Technology Center at Intel hosts PowerTOP and LatencyTOP, and supports other projects such as Wayland, Intel Array Building Blocks, and Threading Building Blocks. Client Computing Group – 55% of 2016 revenues – produces hardware components used in desktop, data Center Group – 29% of 2016 revenues – produces hardware components used in server, network, and storage platforms. Internet of Things Group – 5% of 2016 revenues – offers platforms designed for retail, transportation, industrial, buildings, non-Volatile Memory Solutions Group – 4% of 2016 revenues – manufactures NAND flash memory products primarily used in solid-state drives. Intel Security Group – 4% of 2016 revenues – produces software, particularly security, programmable Solutions Group – 3% of 2016 revenues – manufactures programmable semiconductors. In 2016, Dell accounted for 15% of Intels total revenues, Lenovo accounted for 13% of total revenues, in the 1980s, Intel was among the top ten sellers of semiconductors in the world. In 1991, Intel became the biggest chip maker by revenue and has held the position ever since, other top semiconductor companies include TSMC, Advanced Micro Devices, Samsung, Texas Instruments, Toshiba and STMicroelectronics. Competitors in PC chip sets include Advanced Micro Devices, VIA Technologies, Silicon Integrated Systems, however, the cross-licensing agreement is canceled in the event of an AMD bankruptcy or takeover. Some smaller competitors such as VIA Technologies produce low-power x86 processors for small factor computers, however, the advent of such mobile computing devices, in particular, smartphones, has in recent years led to a decline in PC sales. Since over 95% of the worlds smartphones currently use processors designed by ARM Holdings, ARM is also planning to make inroads into the PC and server market. Intel has been involved in disputes regarding violation of antitrust laws. Intel was founded in Mountain View, California in 1968 by Gordon E. Moore, a chemist, and Robert Noyce, arthur Rock helped them find investors, while Max Palevsky was on the board from an early stage. Moore and Noyce had left Fairchild Semiconductor to found Intel, Rock was not an employee, but he was an investor and was chairman of the board
5.
Thesis
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A thesis or dissertation is a document submitted in support of candidature for an academic degree or professional qualification presenting the authors research and findings. In some contexts, the thesis or a cognate is used for part of a bachelors or masters course, while dissertation is normally applied to a doctorate, while in other contexts. The term graduate thesis is used to refer to both masters theses and doctoral dissertations. The required complexity or quality of research of a thesis or dissertation can vary by country, university, or program, the word dissertation can at times be used to describe a treatise without relation to obtaining an academic degree. The term thesis is used to refer to the general claim of an essay or similar work. The term thesis comes from the Greek θέσις, meaning something put forth, Dissertation comes from the Latin dissertātiō, meaning path. A thesis may be arranged as a thesis by publication or a monograph, with or without appended papers, an ordinary monograph has a title page, an abstract, a table of contents, comprising the various chapters, and a bibliography or a references section. They differ in their structure in accordance with the different areas of study. In a thesis by publication, the chapters constitute an introductory, Dissertations normally report on a research project or study, or an extended analysis of a topic. The structure of the thesis or dissertation explains the purpose, the research literature which impinges on the topic of the study, the methods used. Degree-awarding institutions often define their own style that candidates have to follow when preparing a thesis document. Other applicable international standards include ISO2145 on section numbers, ISO690 on bibliographic references, some older house styles specify that front matter uses a separate page-number sequence from the main text, using Roman numerals. They therefore avoid the traditional separate number sequence for front matter, however, strict standards are not always required. Most Italian universities, for example, have only general requirements on the size and the page formatting. A thesis or dissertation committee is a committee that supervises a students dissertation, the committee members are doctors in their field and have the task of reading the dissertation, making suggestions for changes and improvements, and sitting in on the defense. Sometimes, at least one member of the committee must be a professor in a department that is different from that of the student, all the dissertation referees must already have achieved at least the academic degree that the candidate is trying to reach. At English-speaking Canadian universities, writings presented in fulfillment of undergraduate coursework requirements are normally called papers, a longer paper or essay presented for completion of a 4-year bachelors degree is sometimes called a major paper. High-quality research papers presented as the study of a postgraduate consecutive bachelor with Honours or Baccalaureatus Cum Honore degree are called thesis
6.
David D. Clark
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David Dana Dave Clark is an American computer scientist and Internet pioneer who has been involved with Internet developments since the mid-1970s. He currently works as a Senior Research Scientist at MITs Computer Science and he graduated from Swarthmore College in 1966. In 1968, he received his Masters and Engineers degrees in Electrical Engineering from MIT and he received his Ph. D. in Electrical Engineering from MIT in 1973. From 1981 to 1989, he acted as chief architect in the development of the Internet, and chaired the Internet Activities Board. He has also served as chairman of the Computer Sciences and Telecommunications Board of the National Research Council, in 1990 he was awarded the SIGCOMM Award in recognition of his major contributions to Internet protocol and architecture. Clark received in 1998 the IEEE Richard W. Hamming Medal, in 2001 he was inducted as a Fellow of the Association for Computing Machinery
7.
Spanning Tree Protocol
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The Spanning Tree Protocol is a network protocol that builds a logical loop-free topology for Ethernet networks. The basic function of STP is to prevent bridge loops and the broadcast radiation that results from them, Spanning tree also allows a network design to include spare links to provide automatic backup paths if an active link fails. This is done without the danger of bridge loops, or the need for enabling or disabling of these backup links. STP is based on an algorithm that was invented by Radia Perlman while she was working for Digital Equipment Corporation, to break loops in the LAN while maintaining access to all LAN segments, the bridges collectively compute a spanning tree. The spanning tree that the bridges compute using the Spanning Tree Protocol can be determined using the following rules, the example network at the right, below, will be used to illustrate the rules. The root bridge of the tree is the bridge with the smallest bridge ID. Each bridge has a priority number and a MAC address, the bridge ID is the concatenation of the bridge priority. The bridge priority default is 32768 and can only be configured in multiples of 4096, when comparing two bridge IDs, the priority portions are compared first and the MAC addresses are compared only if the priorities are equal. The switch with the lowest priority of all the switches will be the root, if there is a tie, then the switch with the lowest priority and lowest MAC address will be the root. For example, if switches A and B both have a priority of 32768 then switch A will be selected as the root bridge, if the network administrators would like switch B to become the root bridge, they must set its priority to be less than 32768. Determine the least cost paths to the root bridge, the cost of traversing a path is the sum of the costs of the segments on the path. Different technologies have different default costs, an administrator can configure the cost of traversing a particular network segment. The property that messages always traverse least-cost paths to the root is guaranteed by the two rules. Least cost path from each bridge, after the root bridge has been chosen, each bridge determines the cost of each possible path from itself to the root. The calculation is done by comparing the root path cost of the BPDUs that each bridge gets on each of its ports. The root bridge sends BPDUs with path cost equal to zero, the port that gets the BPDU with the smallest path cost then becomes the root port of the bridge. Least cost path from each network segment, the bridges on a network segment collectively determine which bridge has the least-cost path from the network segment to the root. The port connecting this bridge to the segment is then the designated port for the segment
8.
Bridging (networking)
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A network bridge is a computer networking device that creates a single aggregate network from multiple communication networks or network segments. This function is called network bridging, bridging is distinct from routing, which allows multiple different networks to communicate independently while remaining separate. In the OSI model, bridging is performed in the first two layers, below the network layer, if one or more segments of the bridged network are wireless, the device is known as a wireless bridge and the function as wireless bridging. There are four types of network bridging technologies, simple bridging, multiport bridging, learning or transparent bridging, a simple bridge connects two network segments, typically by operating transparently and deciding on a frame-by-frame basis whether or not to forward from one network to the other. A store and forward technique is used so, during forwarding. Contrary to repeaters that extend the maximum span of a segment. Additionally, bridges reduce collisions by partitioning the collision domain, a multiport bridge connects multiple networks and operates transparently to decide on a frame-by-frame basis whether and where to forward traffic. Like the simple bridge, a multiport bridge typically uses store, the multiport bridge function serves as the basis for network switches. A transparent bridge uses a database to send frames across network segments. The forwarding database starts empty - entries in the database are built as the bridge receives frames. If an address entry is not found in the forwarding database, by means of these flooded frames, the destination network will respond and a forwarding database entry will be created. In the context of a bridge, one can think of the forwarding database as a filtering database. A bridge reads a frames destination address and decides to forward or filter. If the bridge determines that the node is on another segment on the network. If the destination address belongs to the segment as the source address. As nodes transmit data through the bridge, the bridge establishes a filtering database of known MAC addresses, the bridge uses its filtering database to determine whether a frame should be forwarded or filtered. Transparent bridging can also operate over devices with more than two ports, as an example, consider a bridge connected to three hosts, A, B, and C. A is connected to bridge port 1, B is connected to bridge port 2, C is connected to bridge port 3, a sends a frame addressed to B to the bridge
9.
Digital Equipment Corporation
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Digital Equipment Corporation, also known as DEC and using the trademark Digital, was a major American company in the computer industry from the 1950s to the 1990s. DEC was a vendor of computer systems, including computers, software. Their PDP and successor VAX products were the most successful of all minicomputers in terms of sales, DEC was acquired in June 1998 by Compaq, in what was at that time the largest merger in the history of the computer industry. At the time, Compaq was focused on the market and had recently purchased several other large vendors. DEC was a major player overseas where Compaq had less presence, however, Compaq had little idea what to do with its acquisitions, and soon found itself in financial difficulty of its own. The company subsequently merged with Hewlett-Packard in May 2002, as of 2007 some of DECs product lines were still produced under the HP name. From 1957 until 1992, DECs headquarters were located in a wool mill in Maynard. DEC was acquired in June 1998 by Compaq, which merged with Hewlett-Packard in May 2002. Some parts of DEC, notably the business and the Hudson. Initially focusing on the end of the computer market allowed DEC to grow without its potential competitors making serious efforts to compete with them. Their PDP series of machines became popular in the 1960s, especially the PDP-8, looking to simplify and update their line, DEC replaced most of their smaller machines with the PDP-11 in 1970, eventually selling over 600,000 units and cementing DECs position in the industry. Originally designed as a follow-on to the PDP-11, DECs VAX-11 series was the first widely used 32-bit minicomputer and these systems were able to compete in many roles with larger mainframe computers, such as the IBM System/370. The VAX was a best-seller, with over 400,000 sold, at its peak, DEC was the second largest employer in Massachusetts, second only to the Massachusetts State Government. The rapid rise of the business microcomputer in the late 1980s, DECs last major attempt to find a space in the rapidly changing market was the DEC Alpha 64-bit RISC instruction set architecture. DEC initially started work on Alpha as a way to re-implement their VAX series, DEC was acquired in June 1998 by Compaq, in what was at that time the largest merger in the history of the computer industry. At the time, Compaq was focused on the market and had recently purchased several other large vendors. DEC was a major player overseas where Compaq had less presence, however, Compaq had little idea what to do with its acquisitions, and soon found itself in financial difficulty of its own. The company subsequently merged with Hewlett-Packard in May 2002, as of 2007 some of DECs product lines were still produced under the HP name
10.
Dell EMC
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Dell EMC is an American multinational corporation headquartered in Hopkinton, Massachusetts, United States. Dell EMC sells data storage, information security, virtualization, analytics, cloud computing and other products and services enable organizations to store, manage, protect. Dell EMCs target markets include large companies and small- and medium-sized businesses across various vertical markets, the stock was added to the New York Stock Exchange on April 6,1986, and was also listed on the S&P500 index. EMC had over 70,000 employees and was the world’s largest provider of systems by market share, competing against NetApp, IBM, Hewlett Packard Enterprise. Joseph M. Tucci had served as EMCs chief executive since January 2001 and chairman of the board of directors since January 2006, he joined the company in 2000 as president and chief operating officer. Tucci was also chairman of the board of VMware Corporation and chairman of the board of Pivotal Software, on October 12,2015, Dell Inc. announced that it would acquire EMC in a cash-and-stock deal valued at $67 billion—the largest-ever acquisition in the technology industry. The merger closed on September 7,2016, EMC has been renamed to Dell EMC as a result of the merger. The full form of former name EMC2 is Egan, Marino, Connolly & Curley. In the mid-1980s the company expanded beyond memory to other data storage types. EMC began shipping its product, the Symmetrix, in 1990. Symmetrix was the reason for EMCs rapid growth in the 1990s. Michael Ruettgers joined EMC in 1988 and served as CEO from 1992 until January 2001, under Ruettgers’ leadership, EMC revenues grew from $120 million to nearly $9 billion 10 years later, and the company shifted its focus from memory boards to storage systems. In 2001, Joe Tucci was named executive officer of EMC. Under Tuccis leadership, EMC grew to $21.7 billion in revenues in 2012, in 2009, EMC and Cisco, with investments from VMware and Intel, formed a joint venture called VCE to develop products and services for the converged infrastructure and cloud computing markets. EMC announced its 450,000 square foot Center of Excellence in Durham, the COE houses a virtualized data center and includes 130,000 square feet of global research and development labs. In 2013, EMC launched a new company named Pivotal, led by Paul Maritz, the organization combines technologies from VMware and EMC and is focused on delivering Platform-as-a-Service products. EMC has been growing in part through aggressively making acquisitions of small companies, on October 12,2015, Dell Inc. announced its intent to acquire EMC in a cash-and-stock deal valued at $67 billion, which has been considered the largest-ever acquisition in the technology sector. The deal is structured so that Dell will pay $24.05 per share of EMC, in addition to those of the majority-owned VMware and Pivotal companies, EMC sells products and services designed to allow IT departments to move to a cloud computing model and to analyze big data. The following table includes the listing and timeline of EMC Corporations major acquisitions of companies since 1996
11.
Asbury Park, New Jersey
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Asbury Park is a city in Monmouth County, New Jersey, United States, located on the Jersey Shore and part of the New York City Metropolitan Area. It was ranked the sixth-best beach in New Jersey in the 2008 Top 10 Beaches Contest sponsored by the New Jersey Marine Sciences Consortium. Asbury Park was originally incorporated as a borough by an act of the New Jersey Legislature on March 26,1874, the borough was reincorporated on February 28,1893. Asbury Park was incorporated as a city, its current type of government, a seaside community, Asbury Park is located on New Jerseys central coast. Bradley was active in the development of much of the citys infrastructure, along the waterfront Bradley installed the Asbury Park Boardwalk, an orchestra pavilion, public changing rooms and a pier at the south end of that boardwalk. During these early decades in Asbury Park, a number of hotels were built. Uriah White, an Asbury Park pioneer, installed the first artesian well water system, by 1912, The New York Times estimated that the summer population could reach 200,000. The country by the sea destination experienced several key periods of popularity, the first notable era was the 1890s, marked by a housing growth, examples of which can still be found today in a full range of Victorian architecture. Coinciding with the trend in retail shopping, Asbury Parks downtown flourished during this period. The 1920s saw a change in the boardwalk with the construction of the Paramount Theatre and Convention Hall complex, the Casino Arena and Carousel House. Beaux Arts architect Warren Whitney of New York was the designer and he had also been hired to design the imposing Berkeley-Carteret Hotel positioned diagonally across from the theater and hall. At the same time, Asbury Park launched a first-class education, in 1935, the newly founded Securities and Exchange Commission called Asbury Parks Mayor Clarence F. Hetrick to testify about $6,000,000 in beach improvement bonds that had gone into default. The interests of Asbury Parks bond investors lead Senator Frank Durand to add a last-minute Beach Commission amendment to a municipal debt bill in the New Jersey legislature, when the bill became law, it ceded control of the Asbury Park beach to Governor Harold Hoffman and a governors commission. The city of Asbury Park sued to restore control of the beach to the municipal council, in 1943, the New York Yankees held their spring training in Asbury Park instead of Florida. This was because rail transport had to be conserved during the war, with the opening of the Garden State Parkway in 1947, Asbury Park saw the travel market change as fewer vacationers took trains to the seashore. Office parks built outside the city resulted in the relocation of accountants, dentists, doctors, lawyers, many of those city blocks have yet to be redeveloped into the 21st century. Although it was placed on the National Register of Historic Places, the complex had featured the famous face of Tillie, a symbol of the Jersey Shore. In 1990, the carousel at the Casino Pier was sold to Family Kingdom Amusement Park in Myrtle Beach, South Carolina
12.
New Jersey
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New Jersey is a state in the Northeastern and mid-Atlantic regions of the United States. It is bordered on the north and east by New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania, New Jersey is the fourth-smallest state but the 11th-most populous and the most densely populated of the 50 United States. New Jersey lies entirely within the statistical areas of New York City. New Jersey was inhabited by Native Americans for more than 2,800 years, in the early 17th century, the Dutch and the Swedes made the first European settlements. New Jersey was the site of decisive battles during the American Revolutionary War in the 18th century. In the 19th century, factories in cities such as Camden, Paterson, Newark, Trenton, around 180 million years ago, during the Jurassic Period, New Jersey bordered North Africa. The pressure of the collision between North America and Africa gave rise to the Appalachian Mountains, around 18,000 years ago, the Ice Age resulted in glaciers that reached New Jersey. As the glaciers retreated, they left behind Lake Passaic, as well as rivers, swamps. New Jersey was originally settled by Native Americans, with the Lenni-Lenape being dominant at the time of contact, scheyichbi is the Lenape name for the land that is now New Jersey. The Lenape society was divided into clans that were based upon common female ancestors. These clans were organized into three distinct phratries identified by their animal sign, Turtle, Turkey, and Wolf and they first encountered the Dutch in the early 17th century, and their primary relationship with the Europeans was through fur trade. The Dutch became the first Europeans to lay claim to lands in New Jersey, the Dutch colony of New Netherland consisted of parts of modern Middle Atlantic states. Although the European principle of ownership was not recognized by the Lenape. The first to do so was Michiel Pauw who established a patronship called Pavonia in 1630 along the North River which eventually became the Bergen, peter Minuits purchase of lands along the Delaware River established the colony of New Sweden. During the English Civil War, the Channel Island of Jersey remained loyal to the British Crown and it was from the Royal Square in St. Helier that Charles II of England was proclaimed King in 1649, following the execution of his father, Charles I. The North American lands were divided by Charles II, who gave his brother, the Duke of York, the region between New England and Maryland as a proprietary colony. James then granted the land between the Hudson River and the Delaware River to two friends who had remained loyal through the English Civil War, Sir George Carteret and Lord Berkeley of Stratton, the area was named the Province of New Jersey. Since the states inception, New Jersey has been characterized by ethnic, New England Congregationalists settled alongside Scots Presbyterians and Dutch Reformed migrants
13.
Engineer
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Engineers design materials, structures, and systems while considering the limitations imposed by practicality, regulation, safety, and cost. The word engineer is derived from the Latin words ingeniare and ingenium, the work of engineers forms the link between scientific discoveries and their subsequent applications to human and business needs and quality of life. His/her work is predominantly intellectual and varied and not of a mental or physical character. It requires the exercise of original thought and judgement and the ability to supervise the technical, he/she is thus placed in a position to make contributions to the development of engineering science or its applications. In due time he/she will be able to give authoritative technical advice, much of an engineers time is spent on researching, locating, applying, and transferring information. Indeed, research suggests engineers spend 56% of their time engaged in various information behaviours, Engineers must weigh different design choices on their merits and choose the solution that best matches the requirements. Their crucial and unique task is to identify, understand, Engineers apply techniques of engineering analysis in testing, production, or maintenance. Analytical engineers may supervise production in factories and elsewhere, determine the causes of a process failure and they also estimate the time and cost required to complete projects. Supervisory engineers are responsible for major components or entire projects, Engineering analysis involves the application of scientific analytic principles and processes to reveal the properties and state of the system, device or mechanism under study. Most engineers specialize in one or more engineering disciplines, numerous specialties are recognized by professional societies, and each of the major branches of engineering has numerous subdivisions. Civil engineering, for example, includes structural and transportation engineering and materials engineering include ceramic, metallurgical, mechanical engineering cuts across just about every discipline since its core essence is applied physics. Engineers also may specialize in one industry, such as vehicles, or in one type of technology. Several recent studies have investigated how engineers spend their time, that is, research suggests that there are several key themes present in engineers’ work, technical work, social work, computer-based work, information behaviours. Amongst other more detailed findings, a recent work sampling study found that engineers spend 62. 92% of their time engaged in work,40. 37% in social work. The time engineers spend engaged in activities is also reflected in the competencies required in engineering roles. There are many branches of engineering, each of which specializes in specific technologies, typically engineers will have deep knowledge in one area and basic knowledge in related areas. When developing a product, engineers work in interdisciplinary teams. For example, when building robots an engineering team will typically have at least three types of engineers, a mechanical engineer would design the body and actuators
14.
Radar
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Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the objects location and speed. Radar was developed secretly for military use by several nations in the period before, the term RADAR was coined in 1940 by the United States Navy as an acronym for RAdio Detection And Ranging or RAdio Direction And Ranging. The term radar has since entered English and other languages as a common noun, high tech radar systems are associated with digital signal processing, machine learning and are capable of extracting useful information from very high noise levels. Other systems similar to make use of other parts of the electromagnetic spectrum. One example is lidar, which uses ultraviolet, visible, or near infrared light from lasers rather than radio waves, as early as 1886, German physicist Heinrich Hertz showed that radio waves could be reflected from solid objects. In 1895, Alexander Popov, an instructor at the Imperial Russian Navy school in Kronstadt. The next year, he added a spark-gap transmitter, in 1897, while testing this equipment for communicating between two ships in the Baltic Sea, he took note of an interference beat caused by the passage of a third vessel. In his report, Popov wrote that this phenomenon might be used for detecting objects, the German inventor Christian Hülsmeyer was the first to use radio waves to detect the presence of distant metallic objects. In 1904, he demonstrated the feasibility of detecting a ship in dense fog and he obtained a patent for his detection device in April 1904 and later a patent for a related amendment for estimating the distance to the ship. He also got a British patent on September 23,1904 for a radar system. It operated on a 50 cm wavelength and the radar signal was created via a spark-gap. In 1915, Robert Watson-Watt used radio technology to advance warning to airmen. Watson-Watt became an expert on the use of direction finding as part of his lightning experiments. As part of ongoing experiments, he asked the new boy, Arnold Frederic Wilkins, Wilkins made an extensive study of available units before selecting a receiver model from the General Post Office. Its instruction manual noted that there was fading when aircraft flew by, in 1922, A. Hoyt Taylor and Leo C. Taylor submitted a report, suggesting that this might be used to detect the presence of ships in low visibility, eight years later, Lawrence A. Australia, Canada, New Zealand, and South Africa followed prewar Great Britain, and Hungary had similar developments during the war. Hugon, began developing a radio apparatus, a part of which was installed on the liner Normandie in 1935
15.
Programmer
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A programmer, computer programmer, developer, dev, coder, or software engineer is a person who writes computer software. The term computer programmer can refer to a specialist in one area of programming or to a generalist who writes code for many kinds of software. One who practices or professes a formal approach to programming may also be known as a programmer analyst, a programmers primary computer language is often prefixed to these titles, and those who work in a web environment often prefix their titles with web. The use of the term programmer for these positions is sometimes considered an insulting or derogatory oversimplification. Because Babbages machine was never completed to a standard in her time. The first person to run a program on a functioning modern electronically based computer was computer scientist Konrad Zuse, the ENIAC programming team, consisting of Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas and Ruth Lichterman were the first regularly working programmers. International Programmers Day is celebrated annually on 7 January, in 2009, the government of Russia decreed a professional annual holiday known as Programmers Day to be celebrated on 13 September. It had also been an international holiday before that. Some of this section is from the Occupational Outlook Handbook, 2006–07 Edition, Computer programmers write, test, debug, and maintain the detailed instructions, called computer programs, that computers must follow to perform their functions. Programmers also conceive, design, and test logical structures for solving problems by computer, job titles and descriptions may vary, depending on the organization. Programmers work in many settings, including corporate information technology departments, big companies, small service firms. Many professional programmers also work for consulting companies at client sites as contractors, licensing is not typically required to work as a programmer, although professional certifications are commonly held by programmers. Programming is widely considered a profession, Programmers work varies widely depending on the type of business for which they are writing programs. For example, the involved in updating financial records are very different from those required to duplicate conditions on an aircraft for pilots training in a flight simulator. In most cases, several work together as a team under a senior programmer’s supervision. Programmers write programs according to the specifications determined primarily by more senior programmers, after the design process is complete, it is the job of the programmer to convert that design into a logical series of instructions that the computer can follow. The programmer codes these instructions in one of many programming languages, different programming languages are used depending on the purpose of the program. COBOL, for example, is used for business applications that typically run on mainframe and midrange computers, whereas Fortran is used in science
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Piano
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The piano is an acoustic, stringed musical instrument invented around the year 1700, in which the strings are struck by hammers. It is played using a keyboard, which is a row of keys that the performer presses down or strikes with the fingers and thumbs of both hands to cause the hammers to strike the strings. The word piano is a form of pianoforte, the Italian term for the early 1700s versions of the instrument. The first fortepianos in the 1700s had a sound and smaller dynamic range. An acoustic piano usually has a wooden case surrounding the soundboard and metal strings. Pressing one or more keys on the keyboard causes a padded hammer to strike the strings. The hammer rebounds from the strings, and the continue to vibrate at their resonant frequency. These vibrations are transmitted through a bridge to a soundboard that amplifies by more efficiently coupling the acoustic energy to the air, when the key is released, a damper stops the strings vibration, ending the sound. Notes can be sustained, even when the keys are released by the fingers and thumbs and this means that the piano can play 88 different pitches, going from the deepest bass range to the highest treble. The black keys are for the accidentals, which are needed to play in all twelve keys, more rarely, some pianos have additional keys. Most notes have three strings, except for the bass that graduates from one to two, the strings are sounded when keys are pressed or struck, and silenced by dampers when the hands are lifted from the keyboard. There are two types of piano, the grand piano and the upright piano. The grand piano is used for Classical solos, chamber music and art song and it is used in jazz. The upright piano, which is compact, is the most popular type, as they are a better size for use in private homes for domestic music-making. During the nineteenth century, music publishers produced many works in arrangements for piano, so that music lovers could play. The piano is widely employed in classical, jazz, traditional and popular music for solo and ensemble performances, accompaniment, with technological advances, amplified electric pianos, electronic pianos, and digital pianos have also been developed. The electric piano became an instrument in the 1960s and 1970s genres of jazz fusion, funk music. The piano was founded on earlier technological innovations in keyboard instruments, pipe organs have been used since Antiquity, and as such, the development of pipe organs enabled instrument builders to learn about creating keyboard mechanisms for sounding pitches
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French horn
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The French horn is a brass instrument made of tubing wrapped into a coil with a flared bell. The double horn in F/B♭ is the horn most often used by players in professional orchestras, a musician who plays any kind of horn is generally referred to as a horn player. Most horns have lever-operated rotary valves, but some, especially older horns, use piston valves, the backward-facing orientation of the bell relates to the perceived desirability to create a subdued sound, in concert situations, in contrast to the more piercing quality of the trumpet. A horn without valves is known as a horn, changing pitch along the natural harmonics of the instrument. Pitch may also be controlled by the position of the hand in the bell, the pitch of any note can easily be raised or lowered by adjusting the hand position in the bell. Three valves control the flow of air in the single horn, the more common double horn has a fourth valve, usually operated by the thumb, which routes the air to one set of tubing tuned to F or another tuned to B♭. Triple horns with five valves are made, tuned in F, B♭. Also common are descant doubles, which typically provide B♭ and alto F branches and this configuration provides a high-range horn while avoiding the additional complexity and weight of a triple. A crucial element in playing the horn deals with the mouthpiece, when playing higher notes, the majority of players exert a small degree of additional pressure on the lips using the mouthpiece. It is the goal of all serious brass musicians to develop their technique such that additional mouthpiece pressure is avoided altogether, or at the very least, the name French horn is found only in English, first coming into use in the late 17th century. At that time, French makers were preeminent in the manufacture of hunting horns, as a result, these instruments were often called, even in English, by their French names, trompe de chasse or cor de chasse. The International Horn Society has recommended since 1971 that the instrument be simply called the horn, there is also a more specific use of French horn to describe a particular horn type, differentiated from the German horn and Vienna horn. In this sense, French horn refers to an instrument with three Périnet valves. It retains the narrow bell-throat and mouthpipe crooks of the orchestral hand horn of the late 18th century, and most often has an ascending third valve. This is a whole-tone valve arranged so that with the valve in the up position the valve loop is engaged, the horn is the third-highest-sounding instrument in the brass family, below the trumpet and the cornet. Horns are mostly tuned in B♭ or F, or a combination of both, in some traditions, novice players use a single horn in F, while others prefer the B♭ horn. The F horn is used more commonly than the B♭ horn, sound is produced by vibrating the players lips into the mouthpiece of the instrument. Different partials in the series can be played by adjusting the air pressure and lip tension
18.
Logo (programming language)
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Logo is an educational programming language, designed in 1967 by Daniel G. Bobrow, Wally Feurzeig, Seymour Papert and Cynthia Solomon. It was derived from the Greek logos meaning word or thought by Feurzeig, to itself from other programming languages that were primarily numbers, not graphics or logic. There are substantial differences among the dialects of Logo. Logo is an adaptation and dialect of Lisp, a functional programming language. Logo is usually a language, although there have been developed compiled Logo dialects. Logo is not case-sensitive but retains the case used for formatting, Logo was created in 1967 at Bolt, Beranek and Newman, a Cambridge, Massachusetts research firm, by Wally Feurzeig and Seymour Papert. Its intellectual roots are in intelligence, mathematical logic and developmental psychology. The first four years of Logo research, development and teaching work was done at BBN, the first implementation of Logo, called Ghost, was written in LISP on a PDP-1. The goal was to create a land where children could play with words. Modeled on LISP, the goals of Logo included accessible power. The use of virtual Turtles allowed for immediate feedback and debugging of graphic programming. The first working Logo turtle robot was created in 1969, a display turtle preceded the physical floor turtle. Modern Logo has not changed too much from the basic concepts before the first turtle, the first turtle was a tethered floor roamer, not radio-controlled or wireless. At BBN Paul Wexelblat developed a turtle named Irving that had touch sensors and could move forwards, backwards, rotate, the earliest year-long school users of Logo were in 1968-69 at Muzzey Jr High, Lexington MA. The virtual and physical turtles were first used by fifth graders at the Bridge School in Lexington, Logos most-known feature is the turtle, an on-screen cursor that showed output from commands for movement and small retractable pen, together producing line graphics. It has traditionally been displayed either as a triangle or a turtle icon, as a practical matter, the use of turtle geometry instead of a more traditional model mimics the actual movement logic of the turtle robot. The turtle moves with commands that are relative to its own position, multiple turtles are supported by MSWLogo, as well as 3D graphics. Input from COM ports and LPT ports are also allowed by MSWLogo through windows GUI, interrupts can be triggered via keyboard and mouse events
19.
Debugger
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A debugger or debugging tool is a computer program that is used to test and debug other programs. Some debuggers offer two modes of operation, full or partial simulation, to limit this impact, a trap occurs when the program cannot normally continue because of a programming bug or invalid data. For example, the program might have tried to use an instruction not available on the current version of the CPU or attempted to access unavailable or protected memory, if it is a low-level debugger or a machine-language debugger it shows the line in the disassembly. Typically, debuggers offer a query processor, a symbol resolver, an interpreter. Some debuggers have the ability to modify program state while it is running and it may also be possible to continue execution at a different location in the program to bypass a crash or logical error. It often also makes it useful as a verification tool, fault coverage. Most mainstream debugging engines, such as gdb and dbx, provide console-based command line interfaces, debugger front-ends are popular extensions to debugger engines that provide IDE integration, program animation, and visualization features. Some debuggers include a feature called reverse debugging, also known as historical debugging or backwards debugging and these debuggers make it possible to step a programs execution backwards in time. Microsoft Visual Studio offers IntelliTrace reverse debugging for C#, Visual Basic. NET, and some other languages, reverse debuggers also exist for C, C++, Java, Python, Perl, and other languages. Some are open source, some are commercial software. Some reverse debuggers slow down the target by orders of magnitude, reverse debugging is very useful for certain types of problems, but is still not commonly used yet. Some debuggers operate on a specific language while others can handle multiple languages transparently. Some debuggers also incorporate memory protection to avoid storage violations such as buffer overflow and this may be extremely important in transaction processing environments where memory is dynamically allocated from memory pools on a task by task basis. Most modern microprocessors have at least one of features in their CPU design to make debugging easier, Hardware support for single-stepping a program. In-system programming allows an external hardware debugger to reprogram a system under test, many systems with such ISP support also have other hardware debug support. Hardware support for code and data breakpoints, such as address comparators and data value comparators or, with more work involved. JTAG access to hardware debug interfaces such as those on ARM architecture processors or using the Nexus command set, processors used in embedded systems typically have extensive JTAG debug support. Micro controllers with as few as six pins need to use low pin-count substitutes for JTAG, such as BDM, Spy-Bi-Wire, debugWIRE, for example, uses bidirectional signaling on the RESET pin
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Seymour Papert
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Seymour Aubrey Papert was a South African-born American mathematician, computer scientist, and educator, who spent most of his career teaching and researching at MIT. He was one of the pioneers of artificial intelligence, and of the constructionist movement in education and he was co-inventor, with Wally Feurzeig and Cynthia Solomon, of the Logo programming language. Papert attended the University of the Witwatersrand, receiving a Bachelor of Arts degree in philosophy in 1949 followed by a PhD in mathematics in 1952 and he then went on to receive a second doctorate, also in mathematics, at the University of Cambridge, supervised by Frank Smithies. At MIT, Papert went on to create the Epistemology and Learning Research Group at the MIT Architecture Machine Group which later became the MIT Media Lab. Here, he was the developer of a theory on learning called constructionism, Papert had worked with Piaget at the University of Geneva from 1958 to 1963 and was one of Piagets protégés, Piaget himself once said that no one understands my ideas as well as Papert. Papert has rethought how schools should work, based on theories of learning. Papert used Piagets work in his development of the Logo programming language while at MIT and he created Logo as a tool to improve the way children think and solve problems. A small mobile robot called the Logo Turtle was developed, a main purpose of the Logo Foundation research group is to strengthen the ability to learn knowledge. Papert insisted a simple language or program that children can learn—like Logo—can also have advanced functionality for expert users. Counter-free automata,1971, ISBN 0-262-13076-9 Perceptrons, MIT Press,1969, ISBN 0-262-63111-3 Mindstorms, Children, Computers, Constructionism, research reports and essays 1985 -1990 by the Epistemology and Learning Research Group, the Media Lab, Massachusetts Institute of Technology, Ablex Pub. He was one of the principals for the One Laptop Per Child initiative to manufacture, Papert also collaborated with the construction toy manufacturer Lego on their Logo-programmable Lego Mindstorms robotics kits, which were named after his groundbreaking 1980 book. He was a figure in the revolutionary socialist circle around Socialist Review while living in London in the 1950s. Papert was also a prominent activist against South African apartheid policies during his university education, Papert was married to Dona Strauss, and later to Androula Christofides Henriques. Paperts third wife was MIT professor Sherry Turkle, and together wrote the influential paper Epistemological Pluralism. In his final 24 years, Papert was married to Suzanne Massie and he was moved to a hospital closer to his home in January 2007, but then contracted septicemia which damaged a heart valve, which was later replaced. By 2008 he had returned home, could think and communicate clearly and walk almost unaided and his rehabilitation team used some of the very principles of experiential, hands-on learning that he had pioneered. Papert died at his home in Blue Hill, Maine, on July 31,2016, paperts work has been used by other researchers in the fields of education and computer science. In 1981, Papert along with others in the Logo group at MIT
21.
BBN Technologies
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BBN Technologies is an American high-technology company which provides research and development services. BBN is based next to Fresh Pond in Cambridge, Massachusetts and it is a military contractor, primarily for DARPA, and also known for its 1978 acoustical analysis for the House Select Committee on the assassination of John F. Kennedy. BBN of the 1950s and 1960s has been referred to by two of its alumni as the university of Cambridge, after MIT and Harvard. In 1966, the Franklin Institute awarded the firm the Frank P. Brown Medal, BBN became a wholly owned subsidiary of Raytheon in 2009. On February 1,2013, BBN Technologies was awarded the National Medal of Technology, founded in 1948, by Leo Beranek and Richard Bolt, professors at the Massachusetts Institute of Technology, with Bolts former student Robert Newman. Bolt, Beranek and Newman started life as a consulting company. Their first contract was consultation for the design of the acoustics of the United Nations Assembly Hall in New York. Experts at the company examined the Richard Nixon tape with the 18.5 minutes erased during the Watergate scandal, the substantial calculations required for acoustics work led to an interest, and later business opportunities, in computing. BBN was a pioneer in developing models of roadway and aircraft noise. Some of this technology was used in legal cases where BBN scientists were expert witnesses. BBN bought a number of computers in the late 1950s and early 1960s, BBN was involved in building some of the earliest Internet networks, including ARPANET, MILNET, CSNET, and NEARNET. C. R. Licklider, John McCarthy, Marvin Minsky, Dan Murphy, Severo Ornstein, Seymour Papert, Oliver Selfridge, Bob Thomas, Ray Tomlinson, former board members include Jim Breyer, Anita K. Jones and Gilman Louie. In the 1970s, BBN created Telenet, Inc. to run the first public packet-switched network, in 1989, BBNs acoustical consulting business was spun off into a new corporation, Acentech Incorporated, located across the street from BBN headquarters in Cambridge. BBN formed an early Internet service provider in 1994 as its BBN Planet division, previously traded as BBN on the stock market, the company was purchased by GTE in 1997 as a wholly owned subsidiary. BBN Planet was joined with GTEs national fiber network to become GTE Internetworking, Genuity was later acquired out of bankruptcy by Level 3 Communications in 2003. In September 2009, Raytheon entered into an agreement to acquire BBN as an owned subsidiary. The acquisition was completed on October 29,2009 and the company was valued at approximately $350 million, in December 2014, the domain name bbn. com, the second oldest currently registered domain name on the Internet, was redirected to www. raytheon. com/ourcompany/bbn/. Former BBN employees have formed about a hundred startup companies with varying levels of involvement, including Parlance Corporation
22.
Communications protocol
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These are the rules or standard that defines the syntax, semantics and synchronization of communication and possible error recovery methods. Protocols may be implemented by hardware, software, or a combination of both, Communicating systems use well-defined formats for exchanging various messages. Each message has a meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. The specified behavior is independent of how it is to be implemented. Communications protocols have to be agreed upon by the parties involved, to reach agreement, a protocol may be developed into a technical standard. Multiple protocols often describe different aspects of a single communication, a group of protocols designed to work together are known as a protocol suite, when implemented in software they are a protocol stack. Most recent protocols are assigned by the IETF for Internet communication, the ITU-T handles telecommunications protocols and formats for the PSTN. As the PSTN and Internet converge, the two sets of standards are also being driven towards convergence, the nature of a communication, the actual data exchanged and any state-dependent behaviors, is defined by these specifications. In digital computing systems, the rules can be expressed by algorithms, expressing the algorithms in a portable programming language makes the protocol software operating-system independent. Operating systems usually contain a set of cooperating processes that manipulate shared data to communicate each other. This communication is governed by protocols, which can be embedded in the process code itself. In contrast, because there is no memory, communicating systems have to communicate with each other using a shared transmission medium. Transmission is not necessarily reliable, and individual systems may use different hardware or operating systems, to implement a networking protocol, the protocol software modules are interfaced with a framework implemented on the machines operating system. This framework implements the functionality of the operating system. The best known frameworks are the TCP/IP model and the OSI model and this gave rise to the concept of layered protocols which nowadays forms the basis of protocol design. Systems typically do not use a protocol to handle a transmission. Instead they use a set of cooperating protocols, sometimes called a family or protocol suite. Some of the best known protocol suites are TCP/IP, IPX/SPX, X.25, AX.25, the protocols can be arranged based on functionality in groups, for instance there is a group of transport protocols
23.
Sun Microsystems
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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
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University of Washington
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The University of Washington, commonly referred to as simply Washington, UW, or informally U-Dub, is a public flagship research university in Seattle, Washington, United States. Founded in 1861, Washington is one of the oldest universities on the West Coast, the university has three campuses, the oldest and largest in the University District of Seattle and two others in Tacoma and Bothell. Washington is a member of the Association of American Universities and is ranked among the top 15 universities in the world by a variety of international publications. In athletics, the university competes in the NCAA Division I Pac-12 Conference and its athletic teams are called the Huskies. Seattle was one of several settlements in the mid to late 19th century vying for primacy in the new Washington Territory, in 1854, territorial governor Isaac Stevens recommended the establishment of a university in Washington. Several prominent Seattle-area residents, chief among them Methodist preacher Daniel Bagley and they convinced early founder of Seattle and member of the territorial legislature Arthur A. Denny of the importance of Seattle winning the school. When no site emerged, the legislature, encouraged by Denny, in 1861, scouting began for an appropriate 10 acres site in Seattle to serve as the campus for a new university. Arthur and Mary Denny donated eight acres, and fellow pioneers Edward Lander and Charlie and this tract was bounded by 4th and 6th Avenues on the west and east and Union and Seneca Streets on the north and south. UW opened on November 4,1861, as the Territorial University of Washington, the following year, the legislature passed articles incorporating the University and establishing a Board of Regents. The school struggled initially, closing three times, in 1863 for lack of students, and again in 1867 and 1876 due to shortage of funds. However, Clara Antoinette McCarty Wilt became the first graduate of UW in 1876 when she graduated from UW with a degree in science. By the time Washington entered the Union in 1889, both Seattle and the University had grown substantially, enrollment increased from 30 students to nearly 300, and the relative isolation of the campus had given way to encroaching development. A special legislative committee headed by UW graduate Edmond Meany was created to find a new campus able to serve the growing student population. The committee selected a site on Union Bay northeast of downtown, the university relocated from downtown to the new campus in 1895, moving into the newly built Denny Hall. The regents tried and failed to sell the old campus, the University still owns what is now called the Metropolitan Tract. In the heart of the city, it is among the most valuable pieces of estate in Seattle. The original Territorial University building was torn down in 1908 and its former site houses the Fairmont Olympic Hotel. The sole surviving remnants of UWs first building are four 24-foot, white, hand-fluted cedar and they were salvaged by Edmond S. Meany—one of the Universitys first graduates and the former head of the history department
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Harvard University
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Although never formally affiliated with any denomination, the early College primarily trained Congregationalist and Unitarian clergy. Its curriculum and student body were gradually secularized during the 18th century, james Bryant Conant led the university through the Great Depression and World War II and began to reform the curriculum and liberalize admissions after the war. The undergraduate college became coeducational after its 1977 merger with Radcliffe College, Harvards $34.5 billion financial endowment is the largest of any academic institution. Harvard is a large, highly residential research university, the nominal cost of attendance is high, but the Universitys large endowment allows it to offer generous financial aid packages. Harvards alumni include eight U. S. presidents, several heads of state,62 living billionaires,359 Rhodes Scholars. To date, some 130 Nobel laureates,18 Fields Medalists, Harvard was formed in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. In 1638, it obtained British North Americas first known printing press, in 1639 it was named Harvard College after deceased clergyman John Harvard an alumnus of the University of Cambridge who had left the school £779 and his scholars library of some 400 volumes. The charter creating the Harvard Corporation was granted in 1650 and it offered a classic curriculum on the English university model—many leaders in the colony had attended the University of Cambridge—but conformed to the tenets of Puritanism. It was never affiliated with any denomination, but many of its earliest graduates went on to become clergymen in Congregational. The leading Boston divine Increase Mather served as president from 1685 to 1701, in 1708, John Leverett became the first president who was not also a clergyman, which marked a turning of the college toward intellectual independence from Puritanism. When the Hollis Professor of Divinity David Tappan died in 1803 and the president of Harvard Joseph Willard died a year later, in 1804, in 1846, the natural history lectures of Louis Agassiz were acclaimed both in New York and on the campus at Harvard College. Agassizs approach was distinctly idealist and posited Americans participation in the Divine Nature, agassizs perspective on science combined observation with intuition and the assumption that a person can grasp the divine plan in all phenomena. When it came to explaining life-forms, Agassiz resorted to matters of shape based on an archetype for his evidence. Charles W. Eliot, president 1869–1909, eliminated the position of Christianity from the curriculum while opening it to student self-direction. While Eliot was the most crucial figure in the secularization of American higher education, he was motivated not by a desire to secularize education, during the 20th century, Harvards international reputation grew as a burgeoning endowment and prominent professors expanded the universitys scope. Rapid enrollment growth continued as new schools were begun and the undergraduate College expanded. Radcliffe College, established in 1879 as sister school of Harvard College, Harvard became a founding member of the Association of American Universities in 1900. In the early 20th century, the student body was predominately old-stock, high-status Protestants, especially Episcopalians, Congregationalists, by the 1970s it was much more diversified
26.
USENIX
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The USENIX Association is the Advanced Computing Systems Association. It was founded in 1975 under the name Unix Users Group, focusing primarily on the study and development of Unix and similar systems. In June 1977, a lawyer from AT&T Corporation informed the group that they could not use the word UNIX as it was a trademark of Western Electric and it has since grown into a respected organization among practitioners, developers, and researchers of computer operating systems more generally. Since its founding, it has published a journal entitled. USENIX was started as a technical organization, USENIX has a special interest group for system administrators, LISA, formerly SAGE. USENIXs founding President was Lou Katz, USENIX became the first computing association to provide open access to their conference and workshop papers in 2008. As of 2013, it remains the one to have done so. Since 2011, they have included audio and video recordings of presentations in their open-access materials. This award, also called the Flame award, is handed out annually since 1993
27.
Local area network
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By contrast, a wide area network, not only covers a larger geographic distance, but also generally involves leased telecommunication circuits or Internet links. An even greater contrast is the Internet, which is a system of globally connected business, Ethernet and Wi-Fi are the two most common transmission technologies in use for local area networks. Historical technologies include ARCNET, Token ring, and AppleTalk, the increasing demand and use of computers in universities and research labs in the late 1960s generated the need to provide high-speed interconnections between computer systems. A1970 report from the Lawrence Radiation Laboratory detailing the growth of their Octopus network gave an indication of the situation. A number of experimental and early commercial LAN technologies were developed in the 1970s, Cambridge Ring was developed at Cambridge University starting in 1974. Ethernet was developed at Xerox PARC in 1973–1975, and filed as U. S, in 1976, after the system was deployed at PARC, Robert Metcalfe and David Boggs published a seminal paper, Ethernet, Distributed Packet-Switching for Local Computer Networks. ARCNET was developed by Datapoint Corporation in 1976 and announced in 1977 and it had the first commercial installation in December 1977 at Chase Manhattan Bank in New York. The initial driving force for networking was generally to share storage and printers, there was much enthusiasm for the concept and for several years, from about 1983 onward, computer industry pundits would regularly declare the coming year to be, “The year of the LAN”. In practice, the concept was marred by proliferation of incompatible physical layer and network protocol implementations, typically, each vendor would have its own type of network card, cabling, protocol, and network operating system. Netware dominated the personal computer LAN business from early after its introduction in 1983 until the mid-1990s when Microsoft introduced Windows NT Advanced Server, of the competitors to NetWare, only Banyan Vines had comparable technical strengths, but Banyan never gained a secure base. During the same period, Unix workstations were using TCP/IP networking, early LAN cabling had generally been based on various grades of coaxial cable. This led to the development of 10BASE-T and structured cabling which is still the basis of most commercial LANs today, while fiber-optic cabling is common for links between switches, use of fiber to the desktop is rare. Many LANs use wireless technologies that are built into Smartphones, tablet computers, in a wireless local area network, users may move unrestricted in the coverage area. Wireless networks have become popular in residences and small businesses, because of their ease of installation, guests are often offered Internet access via a hotspot service. Network topology describes the layout of interconnections between devices and network segments, at the data link layer and physical layer, a wide variety of LAN topologies have been used, including ring, bus, mesh and star. At the higher layers, NetBEUI, IPX/SPX, AppleTalk and others were once common, simple LANs generally consist of cabling and one or more switches. A switch can be connected to a router, cable modem, a LAN can include a wide variety of other network devices such as firewalls, load balancers, and network intrusion detection. LANs can maintain connections with other LANs via leased lines, leased services, depending on how the connections are established and secured, and the distance involved, such linked LANs may also be classified as a metropolitan area network or a wide area network
28.
Ethernet
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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
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MAC address
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A media access control address of a computer is a unique identifier assigned to network interfaces for communications at the data link layer of a network segment. MAC addresses are used as an address for most IEEE802 network technologies, including Ethernet. Logically, MAC addresses are used in the access control protocol sublayer of the OSI reference model. MAC addresses are most often assigned by the manufacturer of a network interface controller and are stored in its hardware, if assigned by the manufacturer, a MAC address usually encodes the manufacturers registered identification number and may be referred to as the burned-in address. It may also be known as an Ethernet hardware address, hardware address or physical address and this can be contrasted to a programmed address, where the host device issues commands to the NIC to use an arbitrary address. A network node may have multiple NICs and each NIC must have a unique MAC address, sophisticated network equipment such as a multilayer switch or router may require one or more permanently assigned MAC addresses. MAC addresses are formed according to the rules of one of three numbering name spaces managed by the Institute of Electrical and Electronics Engineers, MAC-48, EUI-48, the IEEE claims trademarks on the names EUI-48 and EUI-64, in which EUI is an abbreviation for Extended Unique Identifier. The original IEEE802 MAC address comes from the original Xerox Ethernet addressing scheme and this 48-bit address space contains potentially 248 or 281,474,976,710,656 possible MAC addresses. The distinction between EUI-48 and MAC-48 identifiers is purely nominal, MAC-48 is used for hardware, EUI-48 is used to identify other devices. Instead, the proprietary term EUI-48 should be used for this purpose, in addition, the EUI-64 numbering system encompasses both MAC-48 and EUI-48 identifiers by a simple translation mechanism. To convert a MAC-48 into an EUI-64, copy the OUI, to convert an EUI-48 into an EUI-64, the same process is used, but the sequence inserted is FF-FE. In both cases, the process can be reversed when necessary. Organizations issuing EUI-64s are cautioned against issuing identifiers that could be confused with these forms, the IEEE has a target lifetime of 100 years for applications using MAC-48 space, but encourages adoption of EUI-64s instead. IPv6 — one of the most prominent standards that uses a Modified EUI-64 — treats MAC-48 as EUI-48 instead and this results in extending MAC addresses to Modified EUI-64 using only FF-FE and with the U/L bit inverted. An Individual Address Block was a 24-bit OUI managed by the IEEE Registration Authority, followed by 12 IEEE-provided bits, an IAB is ideal for organizations requiring fewer than 4097 unique 48-bit numbers. IABs have been replaced with 12-bit MA-S address blocks, addresses can either be universally administered addresses or locally administered addresses. A universally administered address is assigned to a device by its manufacturer. The first three octets identify the organization issued the identifier and are known as the Organizationally Unique Identifier
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Network topology
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Network topology is the arrangement of the various elements of a computer network. Essentially, it is the structure of a network and may be depicted physically or logically. Distances between nodes, physical interconnections, transmission rates, or signal types may differ between two networks, yet their topologies may be identical, an example is a local area network. Conversely, mapping the data flow between the components determines the topology of the network. Two basic categories of network topologies exist, physical topologies and logical topologies, the cabling layout used to link devices is the physical topology of the network. This refers to the layout of cabling, the locations of nodes, a networks logical topology is not necessarily the same as its physical topology. For example, the twisted pair Ethernet using repeater hubs was a logical bus topology carried on a physical star topology. Token ring is a ring topology, but is wired as a physical star from the media access unit. Logical topologies are often associated with media access control methods. Some networks are able to change their logical topology through configuration changes to their routers. The study of network topology recognizes eight basic topologies, point-to-point, bus, star, ring or circular, mesh, tree, hybrid, the simplest topology with a dedicated link between two endpoints. Easiest to understand, of the variations of point-to-point topology, is a point-to-point communications channel that appears, to the user, a childs tin can telephone is one example of a physical dedicated channel. Using circuit-switching or packet-switching technologies, a point-to-point circuit can be set up dynamically, switched point-to-point topologies are the basic model of conventional telephony. The value of a permanent point-to-point network is unimpeded communications between the two endpoints, the value of an on-demand point-to-point connection is proportional to the number of potential pairs of subscribers and has been expressed as Metcalfes Law. In local area networks where bus topology is used, each node is connected to a single cable and this central cable is the backbone of the network and is known as the bus. A signal from the travels in both directions to all machines connected on the bus cable until it finds the intended recipient. If the machine address does not match the address for the data. Alternatively, if the matches the machine address, the data is accepted
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Institute of Electrical and Electronics Engineers
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The Institute of Electrical and Electronics Engineers is a professional association with its corporate office in New York City and its operations center in Piscataway, New Jersey. It was formed in 1963 from the amalgamation of the American Institute of Electrical Engineers, today, it is the worlds largest association of technical professionals with more than 400,000 members in chapters around the world. Its objectives are the educational and technical advancement of electrical and electronic engineering, telecommunications, computer engineering, IEEE stands for the Institute of Electrical and Electronics Engineers. The association is chartered under this full legal name, IEEEs membership has long been composed of engineers and scientists. For this reason the organization no longer goes by the name, except on legal business documents. The IEEE is dedicated to advancing technological innovation and excellence and it has about 430,000 members in about 160 countries, slightly less than half of whom reside in the United States. The major interests of the AIEE were wire communications and light, the IRE concerned mostly radio engineering, and was formed from two smaller organizations, the Society of Wireless and Telegraph Engineers and the Wireless Institute. After World War II, the two became increasingly competitive, and in 1961, the leadership of both the IRE and the AIEE resolved to consolidate the two organizations. The two organizations merged as the IEEE on January 1,1963. The IEEE is incorporated under the Not-for-Profit Corporation Law of the state of New York and it was formed in 1963 by the merger of the Institute of Radio Engineers and the American Institute of Electrical Engineers. The IEEE serves as a publisher of scientific journals and organizer of conferences, workshops. IEEE develops and participates in activities such as accreditation of electrical engineering programs in institutes of higher learning. The IEEE logo is a design which illustrates the right hand grip rule embedded in Benjamin Franklins kite. IEEE has a dual complementary regional and technical structure – with organizational units based on geography and it manages a separate organizational unit which recommends policies and implements programs specifically intended to benefit the members, the profession and the public in the United States. The IEEE includes 39 technical Societies, organized around specialized technical fields, the IEEE Standards Association is in charge of the standardization activities of the IEEE. The IEEE History Center became an organization to the Engineering. The new ETHW is an effort by various engineering societies as a formal repository of topic articles, oral histories, first-hand histories, Landmarks + Milestones. The IEEE History Center is annexed to Stevens University Hoboken, NJ, in 2016, the IEEE acquired GlobalSpec, adding the provision of engineering data for a profit to its organizational portfolio
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Peer-to-peer
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Peer-to-peer computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the application and they are said to form a peer-to-peer network of nodes. Peers are both suppliers and consumers of resources, in contrast to the traditional client-server model in which the consumption, while P2P systems had previously been used in many application domains, the architecture was popularized by the file sharing system Napster, originally released in 1999. The concept has inspired new structures and philosophies in many areas of human interaction, in such social contexts, peer-to-peer as a meme refers to the egalitarian social networking that has emerged throughout society, enabled by Internet technologies in general. While P2P systems had previously used in many application domains. The peer-to-peer movement allowed millions of Internet users to directly, forming groups and collaborating to become user-created search engines, virtual supercomputers. The basic concept of peer-to-peer computing was envisioned in earlier systems and networking discussions, reaching back to principles stated in the first Request for Comments. The early Internet was more open than present day, where two machines connected to the Internet could send packets to each other without firewalls and other security measures and this contrasts to the broadcasting-like structure of the web as it has developed over the years. As a precursor to the Internet, ARPANET was a successful client-server network where every participating node could request, however, ARPANET was not self-organized, and it lacked the ability to provide any means for context or content-based routing beyond simple address-based routing. Therefore, a messaging system that is often likened as an early peer-to-peer architecture was established. USENET was developed in 1979 and is a system that enforces a decentralized model of control, the basic model is a client-server model from the user or client perspective that offers a self-organizing approach to newsgroup servers. However, news servers communicate with one another as peers to propagate Usenet news articles over the group of network servers. In May 1999, with more people on the Internet, Shawn Fanning introduced the music. A peer-to-peer network is designed around the notion of equal peer nodes simultaneously functioning as both clients and servers to the nodes on the network. This model of network arrangement differs from the model where communication is usually to. Data is still exchanged directly over the underlying TCP/IP network, but at the application layer peers are able to communicate each other directly. Overlays are used for indexing and peer discovery, and make the P2P system independent from the network topology. Based on how the nodes are linked to each other within the overlay network, unstructured peer-to-peer networks do not impose a particular structure on the overlay network by design, but rather are formed by nodes that randomly form connections to each other
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Network routing
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Routing is the process of selecting a path for traffic in a network, or between or across multiple networks. Packet forwarding is the transit of logically addressed network packets from one interface to another. Intermediate nodes are typically network hardware devices such as routers, bridges, gateways, firewalls, general-purpose computers also forward packets and perform routing, although they have no specially optimized hardware for the task. The routing process usually directs forwarding on the basis of routing tables, thus, constructing routing tables, which are held in the routers memory, is very important for efficient routing. Most routing algorithms use only one path at a time. Multipath routing techniques enable the use of alternative paths. Routing, in a sense of the term, is often contrasted with bridging in its assumption that network addresses are structured. Structured addresses allow a single routing table entry to represent the route to a group of devices, in large networks, structured addressing outperforms unstructured addressing. Routing has become the dominant form of addressing on the Internet, bridging is still widely used within localized environments. This article focuses on unicast routing algorithms, in static routing, small networks may use manually configured routing tables. Larger networks have complex topologies that can change rapidly, making the construction of routing tables unfeasible. Nevertheless, most of the switched telephone network uses pre-computed routing tables. Examples of dynamic-routing protocols and algorithms include Routing Information Protocol, Open Shortest Path First, distance vector algorithms use the Bellman–Ford algorithm. This approach assigns a cost number to each of the links between each node in the network, nodes send information from point A to point B via the path that results in the lowest total cost. The algorithm operates in a simple manner. When a node first starts, it knows of its immediate neighbours. Each node, on a basis, sends to each neighbour node its own current assessment of the total cost to get to all the destinations it knows of. The neighbouring nodes examine this information and compare it to what they know, anything that represents an improvement on what they already have
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Packet switching
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Packet switching increases network efficiency and robustness, and enables technological convergence of many applications operating on the same network. Packets are composed of a header and payload, Information in the header is used by networking hardware to direct the packet to its destination where the payload is extracted and used by application software. This concept contrasted and contradicted then-established principles of pre-allocation of network bandwidth, the new concept found little resonance among network implementers until the independent work of British computer scientist Donald Davies at the National Physical Laboratory in the late 1960s. Packet mode communication may be implemented with or without intermediate forwarding nodes, in case of a shared physical medium, the packets may be delivered according to a multiple access scheme. In the late 1950s, the US Air Force established a wide area network for the Semi-Automatic Ground Environment radar defense system and they sought a system that might survive a nuclear attack to enable a response, thus diminishing the attractiveness of the first strike advantage by enemies. Report P-2626 described a general architecture for a large-scale, distributed, Barans work was known to Robert Taylor and J. C. R. Licklider at the Information Processing Technology Office, who advocated wide area networks, starting in 1965, Donald Davies at the National Physical Laboratory, UK, independently developed the same message routing methodology as developed by Baran. He called it packet switching, a more accessible name than Barans and he gave a talk on the proposal in 1966, after which a person from the Ministry of Defence told him about Barans work. A member of Davies team met Lawrence Roberts at the 1967 ACM Symposium on Operating System Principles, Davies had chosen some of the same parameters for his original network design as did Baran, such as a packet size of 1024 bits. In 1966, Davies proposed that a network should be built at the laboratory to serve the needs of NPL, the NPL Data Communications Network entered service in 1970. In 1974, Vint Cerf and Bob Kahn published the specifications for Transmission Control Protocol, Packet switching may be classified into connectionless packet switching, also known as datagram switching, and connection-oriented packet switching, also known as virtual circuit switching. Examples of connectionless protocols are Ethernet, Internet Protocol, and the User Datagram Protocol, connection-oriented protocols include X.25, Frame Relay, Multiprotocol Label Switching, and the Transmission Control Protocol. In connectionless mode each packet includes complete addressing information, the packets are routed individually, sometimes resulting in different paths and out-of-order delivery. Each packet is labeled with an address, source address. It may also be labeled with the number of the packet. At the destination, the original message/data is reassembled in the correct order, connection-oriented transmission requires a setup phase in each involved node before any packet is transferred to establish the parameters of communication. The packets include a connection identifier rather than address information and are negotiated between endpoints so that they are delivered in order and with error checking, the signaling protocols used allow the application to specify its requirements and discover link parameters. Acceptable values for service parameters may be negotiated, routing a packet requires the node to look up the connection id in a table
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Distance-vector routing protocol
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Distance-vector routing protocols use the Bellman–Ford algorithm, Ford–Fulkerson algorithm, or DUAL FSM to calculate paths. A distance-vector routing protocol requires that a router inform its neighbors of topology changes periodically, the term distance vector refers to the fact that the protocol manipulates vectors of distances to other nodes in the network. The distance vector algorithm was the original ARPANET routing algorithm and was used in the Internet under the name of RIP. Examples of distance-vector routing protocols include RIPv1 and RIPv2, IGRP, routers using distance-vector protocol do not have knowledge of the entire path to a destination. Instead they use two methods, Direction in which router or exit interface a packet should be forwarded, distance from its destination Distance-vector protocols are based on calculating the direction and distance to any link in a network. Direction usually means the next hop address and the exit interface, distance is a measure of the cost to reach a certain node. The least cost route between any two nodes is the route with minimum distance, each node maintains a vector of minimum distance to every node. The cost of reaching a destination is calculated using various route metrics, RIP uses the hop count of the destination whereas IGRP takes into account other information such as node delay and available bandwidth. RIP supports cross-platform distance vector routing whereas IGRP is a Cisco Systems proprietary distance vector routing protocol, once a router has this information it is able to amend its own routing table to reflect the changes and then inform its neighbors of the changes. There are a number of features which can be used to help with instability, the Bellman–Ford algorithm does not prevent routing loops from happening and suffers from the count-to-infinity problem. The core of the count-to-infinity problem is that if A tells B that it has a path somewhere, there is no way for B to know if the path has B as a part of it. To see the problem clearly, imagine a subnet connected like A–B–C–D–E–F, now suppose that A is taken offline. In the vector-update-process B notices that the route to A, which was distance 1, is down – B does not receive the update from A. The problem is, B also gets an update from C, since B doesnt know that the path from C to A is through itself, it updates its table with the new value B to A =2 +1. Later on, B forwards the update to C and due to the fact that A is reachable through B, C decides to update its table to C to A =3 +1 and this slowly propagates through the network until it reaches infinity. RIP uses the split horizon with poison reverse technique to reduce the chance of forming loops and these measures avoid the formation of routing loops in some, but not all, cases. The addition of a hold time avoids loop formation in all cases. More recently, a number of loop-free distance vector protocols have been developed — notable examples are EIGRP, DSDV and Babel
36.
ARPANET
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The Advanced Research Projects Agency Network was an early packet switching network and the first network to implement the protocol suite TCP/IP. Both technologies became the foundation of the Internet. ARPANET was initially funded by the Advanced Research Projects Agency of the United States Department of Defense, the packet switching methodology employed in the ARPANET was based on concepts and designs by Americans Leonard Kleinrock and Paul Baran, British scientist Donald Davies, and Lawrence Roberts. The TCP/IP communications protocols were developed for ARPANET by computer scientists Robert Kahn and Vint Cerf, as the project progressed, protocols for internetworking were developed by which multiple separate networks could be joined into a network of networks. 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 introduced as the standard networking protocol on the ARPANET. Packet switching—today the dominant basis for data communications worldwide—was a new concept at the time of the conception of the ARPANET, such stations might be telephones or computers. The dedicated line typically comprises many intermediary lines which are assembled into a chain that stretches all the way from the station to the destination station. Thus, not only can the link be shared, much as a single post box can be used to post letters to different destinations and those ideas encompassed many of the features of the contemporary Internet. In October 1963, Licklider was appointed head of the Behavioral Sciences and Command and he convinced Ivan Sutherland and Bob Taylor that this network concept was very important and merited development, although Licklider left ARPA before any contracts were assigned for development. Taylor recalls the circumstance, For each of three terminals, I had three different sets of user commands. So, if I was talking online with someone at S. D. C. and I wanted to talk to someone I knew at Berkeley, or M. I. T. about this, I had to get up from the S. D. C. Terminal, go over and log into the terminal and get in touch with them. Its obvious what to do, If you have three terminals, there ought to be one terminal that goes anywhere you want to go. Donald Davies at the United Kingdoms National Physical Laboratory independently invented the concept in 1965. His work, presented by a colleague, initially caught the attention of ARPANET developers at a conference in Gatlinburg, Tennessee and he gave the first public demonstration, having coined the term packet switching, on 5 August 1968 and incorporated it into the NPL network in England. Larry Roberts at ARPA applied Davies concepts of packet switching for the ARPANET, the NPL network followed by ARPANET were the first two networks in the world to use packet switching, and were themselves connected together in 1973. The NPL network was using line speeds of 768 kbit/s, by mid-1968, Taylor had prepared a complete plan for a computer network, and, after ARPAs approval, a Request for Quotation was issued for 140 potential bidders. Most computer science companies regarded the ARPA–Taylor proposal as outlandish, and only twelve submitted bids to build a network, of the twelve, at years end, ARPA considered only two contractors, and awarded the contract to build the network to BBN Technologies on 7 April 1969
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Internet Protocol
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The Internet Protocol is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet, IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered and it also defines addressing methods that are used to label the datagram with source and destination information. The Internet protocol suite is often referred to as TCP/IP. The first major version of IP, Internet Protocol Version 4, is the dominant protocol of the Internet and its successor is Internet Protocol Version 6. The Internet Protocol is responsible for addressing hosts and for routing datagrams from a source host to a destination host across one or more IP networks. For this purpose, the Internet Protocol defines the format of packets, each datagram has two components, a header and a payload. The IP header is tagged with the source IP address, the destination IP address, the payload is the data that is transported. This method of nesting the data payload in a packet with a header is called encapsulation, IP addressing entails the assignment of IP addresses and associated parameters to host interfaces. The address space is divided into networks and subnetworks, involving the designation of network or routing prefixes, IP routing is performed by all hosts, as well as routers, whose main function is to transport packets across network boundaries. Routers communicate with one another via specially designed routing protocols, either interior gateway protocols or exterior gateway protocols, IP routing is also common in local networks. For example, many Ethernet switches support IP multicast operations and these switches use IP addresses and Internet Group Management Protocol to control multicast routing but use MAC addresses for the actual routing. The versions currently relevant are IPv4 and IPv6, in May 1974, the Institute of Electrical and Electronic Engineers published a paper entitled A Protocol for Packet Network Intercommunication. The papers authors, Vint Cerf and Bob Kahn, described a protocol for sharing resources using packet switching among network nodes. A central control component of this model was the Transmission Control Program that incorporated both connection-oriented links and datagram services between hosts, the model became known as the Department of Defense Internet Model and Internet protocol suite, and informally as TCP/IP. IP versions 0 to 3 were experimental versions, used between 1977 and 1979, IEN26, dated February 1978 describes a version of the IP header that uses a 1-bit version field. IEN28, dated February 1978 describes IPv2, IEN41, dated June 1978 describes the first protocol to be called IPv4. The IP header is different from the modern IPv4 header, IEN44, dated June 1978 describes another version of IPv4, also with a header different from the modern IPv4 header
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AppleTalk
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AppleTalk was a proprietary suite of networking protocols developed by Apple Inc. for their Macintosh computers. AppleTalk includes a number of features that allow local area networks to be connected with no setup or the need for a centralized router or server of any sort. Connected AppleTalk-equipped systems automatically assign addresses, update the distributed namespace, AppleTalk was released in 1985, and was the primary protocol used by Apple devices through the 1980s and 1990s. Versions were also released for the IBM PC and compatibles and the Apple IIGS, AppleTalk support was also available in most networked printers, some file servers, and a number of routers. The rise of TCP/IP during the 1990s led to a reimplementation of most of these types of support on that protocol, many of AppleTalks more advanced autoconfiguration features have since been introduced in Bonjour, while Universal Plug and Play serves similar needs. After the release of the Apple Lisa computer in January 1983, known as AppleNet, it was based on the seminal Xerox XNS protocol stack but running on a custom 1 Mbit/s coaxial cable system rather than Xeroxs 2.94 Mbit/s Ethernet. AppleNet was announced early in 1983 with an introduction at the target price of $500 for plug-in AppleNet cards for the Lisa. At that time, early LAN systems were just coming to market, including Ethernet, Token Ring and this was a topic of major commercial effort at the time, dominating shows like the National Computer Conference in Anaheim in May 1983. All of the systems were jockeying for position in the market and it was at this show that Steve Jobs asked Gursharan Sidhu a seemingly innocuous question, Why has networking not caught on. Four months later, in October, AppleNet was cancelled, at the time, they announced that Apple realized that its not in the business to create a networking system. We built and used AppleNet in-house, but we realized if we had shipped it. In January, Jobs announced that they would instead be supporting IBMs Token Ring, through this period, Apple was deep in development of the Macintosh computer. During development, engineers had made the decision to use the Zilog 8530 serial controller chip instead of the lower cost and more common UART to provide serial port connections. The SCC cost about $5 more than a UART, but offered much higher speeds up to 250 kilobits per second, the SCC was chosen because it would allow multiple devices to be attached to the port. Peripherals equipped with similar SCCs could communicate using the built-in protocols and this would eliminate the need for more ports on the back of the machine, and allowed for the elimination of expansion slots for supporting more complex devices. The initial concept was known as AppleBus, envisioning a system controlled by the host Macintosh polling dumb devices in a similar to the modern Universal Serial Bus. The Macintosh team had begun work on what would become the LaserWriter. A series of memos from Bob Belleville clarified these concepts, outlining the Mac, LaserWriter, by late 1983 it was clear that IBMs Token Ring would not be ready in time for the launch of the Mac, and might miss the launch of these other products as well
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