Saturday, September 15, 2007

General Motors Corporation


General Motors

General Motors Corporation

GM logo

Type

Public (NYSE: GM

Founded

1908

Headquarters

Flag of the United StatesDetroit, Michigan, USA
manufacturing facilities in 30 U.S. states and 33 countries

Key people

Rick Wagoner, Chairman & CEO
Robert A. Lutz, Vice Chairman
Frederick Henderson, CFO

Industry

Automotive

Products

Automobiles
Engines

Revenue

$207.349 billion USD (2006)[2]

Net income

$1.978 billion USD (2006)[3]

Employees

284,000 (2007) [1]

Website

www.gm.com

General Motors Corporation, also known as GM or The General, an American multinational corporation, is the world's largest auto company by annual production volume for 2006, and the second largest by sales volume as of the first half of 2007, behind Toyota Motor Corporation. [4] Founded in 1908, in Flint, Michigan, GM employs approximately 284,000 people around the world. With global headquarters at the Renaissance Center in Detroit, Michigan, USA, GM manufactures its cars and trucks in 33 countries. Their European headquarters are based in Zurich, Switzerland.Their Holden headquarters are in Melbourne, Victoria, Australia. In 2006, 9.18 million GM cars and trucks were produced globally under the following brands: Buick, Cadillac, Chevrolet, GMC, Holden, Hummer, Opel, Pontiac, Saab, Saturn and Vauxhall. GM is the majority shareholder in GM Daewoo Auto & Technology Co. of South Korea and has had collaborative ventures in technology and manufacturing with several of the world's automakers. It has ventures with Shanghai Automotive Industry Corporation of China.

GM Parts and accessories are sold under GM Performance Parts, GM Goodwrench and ACDelco brands through GM Service and Parts Operations which supplies GM dealerships and distributors worldwide. GM engines and transmissions are marketed through GM Powertrain. GM's largest national market is the United States, followed by China, Canada, the United Kingdom, and Germany. GM half owns a finance company, General Motors Acceptance Corporation Financial Services, which offers automotive, residential and commercial financing and insurance. GM's OnStar subsidiary is a vehicle safety, security and information service provider.

Contents

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[edit] History

Main article: History of General Motors

The Renaissance Center in Detroit, Michigan, is General Motors' world headquarters.

The Renaissance Center in Detroit, Michigan, is General Motors' world headquarters.

General Motors (GM) was founded on September 16, 1908 in Flint, Michigan, as a holding company for Buick, then controlled by William C. Durant, and acquired Oldsmobile later that year. The next year, Durant brought in Cadillac, Elmore, Oakland (later known as Pontiac) and several others. In 1909, General Motors acquired the Reliance Motor Truck Company of Owosso, Michigan, and the Rapid Motor Vehicle Company of Pontiac, Michigan, the predecessors of GMC Truck. Durant lost control of GM in 1910 to a bankers' trust, because of the large amount of debt taken on in its acquisitions - around US$1.0 million.

[edit] Corporate governance

Current members of the board of directors of General Motors are: Percy Barnevik, Erskine Bowles, John Bryan, Armando Codina, Erroll Davis, George Fisher, Karen Katen, Kent Kresa, Ellen Kullman, Philip Laskawy, Kathryn V. Marinello, Eckhard Pfeiffer, and Richard Wagoner (chairman). Jerome York, who was elected to the board on February 6, 2006 to represent Kirk Kerkorian, abruptly resigned on October 6, 2006, following the decision by GM to break off talks about an alliance with Nissan and Renault.

Rick Wagoner is also the chief executive officer of the company (since June 1, 2000), succeeding John F. Smith, Jr.

[edit] Corporate structure

General Motors is structured into the following groups:

  • GM Automotive
    • GMAP - Asia Pacific
    • GME - Europe
    • GMLAAM - Latin America Africa Mid-East
    • GMNA - North America
  • GMAC Finance and insurance services
  • Other Operations

[edit] Social policies

UAW-GM Center for Human Resources in Detroit.

UAW-GM Center for Human Resources in Detroit.

General Motors was named one of the "100 Best Companies for Working Mothers" in 2004 by Working Mothers magazine. GM has also given millions of dollars in computers to colleges of Engineering through its PACE Awards program.[5] Together with the United Auto Workers, GM created a joint venture dedicated to the quality of life needs of employees in 1985. The UAW-GM Center for Human Resources in Detroit is dedicated to providing GM salaried employees and GM UAW members programs and services related to medical care, diversity issues, education, training and tuition assistance, as well as programs related to work and family concerns, in addition to the traditional union-employer health and safety partnership.[6]

[edit] Marketing

At one time, each of GM's automotive divisions were targeted to specific market segments and despite some shared components, each distinguished itself from its stablemates with unique styling and technology. The shared components and common corporate management created substantial economies of scale, while the distinctions between the divisions created an orderly upgrade path, with an entry-level buyer starting out with a practical and economical Chevrolet and moving through offerings of the different divisions until the purchase of a Cadillac. The divisions were not competing with each other as much as passing along the same customer who would thus always be buying a GM product.

The postwar automobile industry became enamored with the concept of "planned obsolescence", implemented by both technical and styling innovations with a typical 3-year product cycle. In this cycle, a new basic body shell is introduced and then modified for the next two years with minor styling changes. GM, Ford, and Chrysler competed vigorously in this new restyling environment.

[edit] Distinguishing the brands

By 1958, the divisional distinctions within GM began to blur with the availability of high-performance engines in Chevrolets and Pontiacs. The introduction of higher trim models such as the Chevrolet Impala and Pontiac Bonneville priced in line with some Oldsmobile and Buick offerings was also confusing to consumers. By the time Pontiac, Oldsmobile and Buick introduced similarly styled and priced compact models in 1961, the old "step-up" structure between the divisions was nearly over.

[edit] Compacts arrive

The 1960s saw the creation of compact and intermediate classes. The Chevrolet Corvair was a 6-cylinder answer to the Volkswagen Beetle, the Chevy II was created to match Ford's conventional Falcon and the Chevrolet Camaro/Pontiac Firebird was GMs counter measure to the Ford Mustang. Among intermediates, the Oldsmobile Cutlass nameplate became so popular during the 1970s that Oldsmobile applied the Cutlass name to most of its products in the 1980s. By the mid 1960s, most of GM's vehicles were built on a few common platforms and in the 1970s GM began to use nearly identical body panel stampings, differing only in internal and external trim items.

The 1971 Chevrolet Vega was GMs launch into the new subcompact class. Problems associated with its innovative aluminum engines would damage GMs reputation more than perhaps any other vehicle in its history. During the late 1970s, GM would initiate a wave of downsizing starting with the Chevrolet Caprice which was reborn into what was the size of the Chevrolet Chevelle, the Malibu would be the size of the Nova, and the Nova was replaced by the troubled front-wheel drive Citation.

[edit] Rebadging era

By the 1980s, GM frequently "rebadged" one division's successful vehicle into several models across the divisions, all positioned close to one another in the market place. Thus a new GM model's main competition might be another model spawned off the same platform. This led to market "cannibalization" with the divisions spending time stealing sales from one another. Even today, the company's GMT360 mid-sized light truck platform has spawned the basic Chevrolet Trailblazer, Oldsmobile Bravada, GMC Envoy, Isuzu Ascender, Buick Rainier and Saab 9-7X. Though each model had a more or less unique mission, the trucks can hardly be discerned from one another.

[edit] GM in the new century

In the late 1990s, the U.S. economy was on the rise and GM and Ford gained market share producing enormous profits primarily from the sale of light trucks and sport-utility vehicles. From 2000 to 2001, the Federal Reserve in a move to quell the stock market, made twelve successive interest rate increases. Following the September 11, 2001 attacks, a severe stock market decline caused a pension and benefit fund underfunding crisis. GM began its Keep America Rolling campaign, which boosted sales, and other auto makers were forced to follow suit. The U.S. automakers saw sales increase to leverage costs as gross margins deteriorated. Although retiree health care costs remain a significant issue, General Motors' investment strategy has generated a $17.1 billion surplus in 2007 in its $101 billion U.S pension fund portfolio, a $35 billion reversal from its $17.8 billion of underfunding.[7]

In 2004, GM redirected resources from the development of new sedans to an accelerated refurbishment of their light trucks and SUVs for introduction as 2007 models in early 2006. Shortly after this decision, fuel prices increased by over 50% and this in turn affected both the trade-in value of used vehicles and the perceived desirability of new offerings in these market segments. The current marketing plan to extensively tout these revised vehicles as offering the best fuel economy in their class (of vehicle). GM claims its hybrid trucks will have gas-mileage improvements of 25%.

In the summer of 2005, GM announced that its corporate chrome emblem "Mark of Excellence" will begin appearing on all recently introduced and all-new 2006 model vehicles produced and sold in North America. The move is seen as an attempt by GM to link its name and vehicle brands more closely.

In 2005, GM promoted sales through an employee discount to all buyers. Marketed as the lowest possible price, GM cleared an inventory buildup of 2005 models to make way for its 2006 lineup. While the promotion was a temporary shot in the arm for sales, it did not help the company's bottom line. GM has since changed its marketing strategy to a no haggle sticker policy in which all vehicle prices are lowered, but incentives are reduced, if not eliminated.

[edit] GM in China

General Motors is the best selling auto maker in China.[8] The Buick brand is especially strong, led by the Buick Excelle subcompact. Cadillac initiated sales in China in 2004, starting with imports from the United States. GM pushed the marketing of the Chevrolet brand in China in 2005 as well, moving the former Buick Sail to that marque. The company manufactures most of its China-market vehicles locally, through its Shanghai GM joint venture. The SAIC-GM-Wuling Automobile joint-venture is also successful selling trucks and vans under the Wuling marque.

[edit] Video News Release

On June 16th, 2006, television station KMSP played a "video news release" about convertibles produced by GM in its entirety. The narrator, Medialink publicist Andrew Schmertz, was introduced as reporter André Schmertz. KMSP did not disclose the corporate source of this segment to their viewers.[1]

[edit] Subsidies

In March 2005, the Government of Canada provided C$200 million in incentives to General Motors for its Ontario plants, and last fall it provided C$100 million to Ford Motor Co. to expand production and provide jobs, according to Jim Harris. Similar incentives were promised to non-North American auto companies like Toyota, Premier Dalton McGuinty said the money the province and Ottawa are pledging for the project is well-spent. His government has committed C$400 million, including the latest Toyota package of C$125 million, to the province's automobile sector, which helped finance $5 billion worth of industry projects. Canada's single payer health care system has helped reduce health care costs for the U.S auto industry.[9]

For the first time, in 2004 the total number of cars produced by all makers in Ontario exceeded those produced in Michigan.

For the first time in 2004 GM sold more vehicles in other countries than inside the US.

[edit] Auto racing

General Motors has an extensive history in numerous forms of racing. Vehicles of most, if not all, of GM's brands have been represented in competition, with perhaps Chevrolet being the most prominent. In particular, the Chevrolet Corvette has long been popular and successful in international road racing. GM also is a supplier of racing components, such as engines, transmissions, and electronics.

GM's Oldsmobile Aurora engine platform was successful in open-wheel Indy-style racing throughout the 1990s, winning many races in the small V-8 class. An unmodified Aurora V-8 in the Aerotech, captured 47 world records, including the record for speed endurance in the Motorsports Hall of Fame of America. Recently, the Cadillac V-Series has entered motorsports racing. GM has also used many cars in the American racing series NASCAR. Currently the Chevrolet Monte Carlo is the only entry in the series but in the past the Pontiac Grand Prix, Buick Regal, Oldsmobile Cutlass, Chevrolet Lumina and Chevrolet Malibu were also used. Starting in March 2007, the Chevrolet Impala will be phased into the series.

In touring cars (mainly in Europe) Vauxhall is a key player and former champion in the British Touring Car Championship (BTCC) series and competes with a Vauxhall Astra VXR in BTC spec. Opel is one of the three participants in the DTM series (along with Audi and Mercedes Benz) and is a former champion and competes with a unique 500 bhp vehicle that resembles the Opel Vectra. Chevrolet competes with a Lacetti in the FIA World Touring Car Championship (WTCC).

In Australia, there is the prestigious V8 Supercar Championship which is battled out by the two main rivals of Holden& Ford. The current Holden Racing Team cars are based on the Holden Commodore and run a 5.0-litre V8-cylinder engine producing 650+BHP (approx 480 kW Power) @ 7500 rpm). These cars have a top speed of 300+km/h (185 mph) and run 0-100 km/h in less than 4 seconds. The Holden Racing Team is Australia's most successful team in Australian Touring Car History. In 2006 both the Teams and Drivers championship was won by the very closely linked Toll HSV Dealer Team

[edit] Environmental record

General Motors is both active in environmental causes and, as a major industrial force, implicated in ecologically harmful activity. The company has long worked on alternative-technology vehicles, and has recently led the industry with clean burning Flexfuel vehicles that can run on either E-85 (ethanol) or gasoline. The company was the first to use turbochargers and was an early proponent of V6 engines in the 1960s, but quickly lost interest as the muscle car race took hold. They demonstrated [2] gas turbine vehicles powered by kerosene, an area of interest throughout the industry in the late 1950s, but despite extensive thermal recycling (developed by Chrysler) the fuel consumption was too high and starting torque too low for everyday use. They were also an early licensee of Wankel engine technology, even developing the Chevrolet Monza around the powerplant, but abandoned the alternative engine configuration in view of the 1973 oil crisis. In the 1970s and 1980s, GM pushed the benefits of diesel engines and cylinder deactivation technologies with disastrous results due to poor durability in the Oldsmobile diesels and drivability issues in the Cadillac 4-6-8 variable cylinder engines. In 1987 GM, in conjunction with Aerovironment built the Sunraycer which won the inaugural World Solar Challenge and was a showcase of advanced technology. Much of the technology from Sunraycer found its way into the Impact prototype electric vehicle (also built by Aerovironment and was the predecessor to the EV1.

General Motors has been criticized for its membership of the anti-Kyoto Protocol Global Climate Coalition and for remaining in the group after other vehicle manufacturers had left [10], as well as for production of increasingly fuel inefficient and environmentally irresponsible vehicles such as the Hummer[11]. GM recently opposed the new CAFE standard increase from 27 mpg to 35 mpg, the first such increase in over 20 years citing it will harm their business.[12] The company’s industrial record has also prompted criticism. Researchers at the University of Massachusetts recently listed General Motors as the 20th largest corporate producer of air pollution in the United States, with 12,771,830 pounds of toxic chemicals released annually into the air.[13] The United States Environmental Protection Agency has linked the corporation to 75 Superfund toxic waste sites, ranking General Motors second only to General Electric and the U.S. Federal Government in the number of Superfund sites for which it is potentially responsible. [14][15]

[edit] Electric vehicles

EV1s crushed by General Motors

EV1s crushed by General Motors

On June 30, 2006 a documentary about the demise of the EV1 and other electric vehicles entitled "Who Killed the Electric Car?" debuted in theatres across America, sparking criticism of the motivation behind the cancellation of their electric car program.

Consumer advocates, activists, commentators, journalists, and documentary makers claim GM had deliberately sabotaged their company's zero emission electric vehicle efforts through several methods: failing to market, failing to produce appropriate vehicles, failing to satisfy demand, and using lease-only programs with prohibitions against end of lease purchase.[3] [4] [5] [6] [7]

The process of obtaining the EV1, GM's first electric vehicle, was difficult. The vehicle could not be purchased outright. Instead, General Motors offered a closed-end lease for three years, with no renewal or residual purchase options. The EV1 was only available from specialist Saturn dealerships, and only in California and Arizona.[8] Before reviewing leasing options, a potential lessee would be taken through a 'pre-qualification' process in order to learn how the EV1 was different from other vehicles. Next came a waiting list with no scheduled delivery date.[9]

Several weeks before the debut of the movie, the Smithsonian Institution announced that its EV1 display was being permanently removed and the EV1 car put into storage. GM is a major financial contributor to the museum, but both parties denied that this fact contributed to the removal of the display.[10]

General Motors has responded to complaints about the scrapping of the EV1 program and they dispute the existence of any conspiracy surrounding its demise. An entry was posted on the GM FastLane Blog in 2006 in which GM defended its decision by saying that it was unable to guarantee the vehicles could continue to be maintained in a safe operating state. [11]

GM alleges that during the four years available to the public, only 800 EV1's were released. Over $1 billion was spent on the EV1 program, with a great portion used for consumer incentives and marketing. With a waiting list of 5,000 applicants, only 50 individuals actually were willing to accept a lease on the EV1. Suppliers ceased production of replacement parts due to the low demand for the EV1. This made repairs and continued safety of the vehicles difficult. The EV1 was designed as a developmental vehicle and was never intended for serial production.

The limitations of storage technology and the expense of production would have made the cars impractical for the vast majority of consumers; a production EV1 would have met limited demand and would have been priced out of reach of most. Had sufficient demand existed to justify mass production and had costs and technologies been able to support mass production, GM would have been more receptive to the idea.

General Motors (GM) has responded to allegations made in the film through a blog post entitled Who Ignored the Facts About the Electric Car?. In it, Dave Barthmuss writes: "Sadly, despite the substantial investment of money and the enthusiastic fervor of a relatively small number of EV1 drivers — including the filmmaker — the EV1 proved far from a viable commercial success." Barthmuss notes investments in electric vehicle technology since the EV1: Two-Mode Hybrid, plug-in hybrid, and fuel cell vehicle programs. The filmmakers suggested that GM did not immediately channel its technological progress with the EV1 into these projects, and instead let the technology languish while focusing on more immediately profitable enterprises such as SUVs. Contrary to this suggestion, as Barthmuss points out, GM is bullish on hydrogen:

According to GM, not all of the EV1's were destroyed. Many were donated to research institutions and facilities, along with museums. Some are still owned by General Motors themselves, and are kept at their Technical Design center in Warren, Michigan, and can occasionally be seen on the road within a close area of the tech center. [12]

There is no other major automaker on the road offering a fully electric vehicle designed for everyday use on public transportation routes, [13] however Think_Nordic, at one time under the ownership of Ford, have produced a range of electric vehicles in limited numbers.

[edit] Hybrid initiative

In May 2004, GM delivered the world's first full sized hybrid pickups, and introduced a hybrid passenger car. In 2005, the Opel Astra diesel Hybrid concept vehicle was introduced. The 2006 Saturn VUE Green Line was the first hybrid passenger vehicle from GM and is also a mild design. GM has hinted at new hybrid technologies to be employed that will be optimized for higher speeds in freeway driving. Future hybrid vehicles should include the 2007 GMC Yukon, the Saturn Aura, and an updated Saturn VUE based an Opel design like the Saturn Aura. GM has recently introduced the concept Chevrolet Volt which is a plug-in hybrid. GM currently offers two types of hybrid systems. The first used in the Silverado Hybrid, Saturn VUE, Saturn Aura, and Chevrolet Malibu is what GM calls a "Mild Hybrid" or "BAS" system. The second hybrid drive was co-developed with DaimlerChrysler and BMW, is called a "two-mode hybrid." The two-mode is used by the Chevrolet Tahoe/GMC Yukon and will later be used on the Saturn VUE.

GM’s current hybrid models:

GM Magic Bus is a hybrid powered bus.[16]

[edit] Hydrogen initiative

GM has prided its research and prototype development of hydrogen powered vehicles, to be produced in early 2010, using a support infrastructure still in a prototype state. The economic feasibility of the technically challenging hydrogen car, and the low-cost production of hydrogen to fuel it, has also been discussed by other automobile manufacturers such as Ford and Chrysler. In June 2007, Larry Burns, vice president of research and development, said he's not yet willing to say exactly when hydrogen vehicles will be mass produced, but he said it should happen before 2020, the year many experts have predicted. He said "I sure would be disappointed if we weren't there" before 2020. [17]

[edit] GM Flexfuel

GM, more than any other automaker, is producing Flexfuel vehicles that can operate on ethanol gasoline, or E85. GM has over 2 million FlexFuel Vehicles on the road today in all 50 states. E85 is a mostly renewable fuel that can be made from U.S.-grown biomass (like corn or grain products) and helps reduce U.S. dependence on foreign petroleum. Although availability is currently limited, U.S.-made E85 is gradually becoming more available to U.S. consumers.

[edit] Corporate restructuring

After gaining market share in the late 1990s and making enormous profits General Motors stock soared to over $80 a share. However, in 2000, twelve successive interest rate hikes by the Federal Reserve led to a severe stock market decline following the September 11, 2001 attacks, caused a pension and benefit funds crisis at General Motors and many other American companies. General Motor's rising retiree health care costs and Other Post Employment Benefit (OPEB) fund deficit prompted the company to enact a broad restructuring plan. Although GM had already taken action to fully fund its pension plan, its OPEB fund became an issue for its corporate bond ratings. GM had expressed its disagreement with the bond ratings; moveover, GM's benefit funds were performing at higher than expected rates of return. Then, following a $10.6 billion loss in 2005, GM acted quickly to implement its restructuring plan. For the first quarter of 2006 GM earned $400 million, signaling a turnaround had already begun even though many aspects of the restructuring plan had not yet taken effect. Although retiree health care costs remain a significant issue, General Motors' investment strategy has generated a $17.1 billion surplus in 2007 in its $101 billion U.S pension fund portfolio, a $35 billion reversal from its $17.8 billion of underfunding.[18]

In February 2005, GM successfully bought itself out of a put option with Fiat for $2 billion USD (€1.55 billion). In 2000, GM had sold a 6% stake to Fiat in return for a 20% share in the Italian automaker. As part of the deal, GM granted Fiat a put option which, if exercised between January 2004 and July 2009, could have forced GM to buy Fiat. GM had agreed to the put option at the time, perhaps to keep it from being acquired by another automaker such as DaimlerChrysler competing with GM's Opel and Vauxhall marques. The relationship suffered, and Fiat had failed to improve. In 2003, Fiat recapitalized, reducing GM's stake to 10%.

In February 2006, GM slashed its annual dividend from 2.00 to $1.00 per share. The reduction saved $565 million a year.

In March 2006, GM divested 92.36 million shares (reducing their stake from 20% to 3%) of Japanese manufacturer Suzuki, in order to raise $2.3 billion. GM originally invested in Suzuki in the early 1980s.

On March 23, a private equity consortium including KKR, Goldman Sachs Capital, and Five Mile Capital purchased $8.8 billion, or 78% of GMAC, GM's commercial mortgage arm. The new entity, in which GMAC will own a 21% stake, will be known as Capmark Financial Group.[19]

On April 3, 2006, GM announced that it would sell 51% of GMAC as a whole to a consortium led by Cerberus Capital Management, raising $14 billion over 3 years. Investors also include Citigroup's private equity arm and Aozora Bank of Japan. The group will pay GM $7.4 billion in cash at closing. GM will retain approximately $20 billion in automobile financing worth an estimated $4 billion over three years.

GM sold its 8% stake in Isuzu on April 11, 2006, to raise an additional $300 million.[20]12,600 workers from Delphi, a key supplier to GM, agreed to buyouts and an early retirement plan offered by GM in order to avoid a strike, after a judge agreed to cancel Delphi's union contracts. 5,000 Delphi workers were allowed to flow to GM.

On June 28, 2007, GM agreed to sell its Allison Transmission division to private-equity firms Carlyle Group and Onex for $5.1 billion. The deal will increase GM's liquidity and echoes previous moves to shift its focus towards its core automotive business. The two firms will control seven factories around Indianapolis but GM will retain management of a factory in Baltimore. Former Allison Transmission president Lawrence E. Dewey will be the new CEO of the standalone company.[14]

As GM opens new plants, those scheduled to close under the planned GM restructuring include (source: General Motors Corporation):

Plants

Location

Closing

Role

# Employees

Moraine Assembly (3rd shift)

Ohio

2006

Mid-size SUV assembly

4,165

Oklahoma City Assembly

Oklahoma

Early 2006

Mid-size trucks and SUV assembly

2,734

Lansing Craft Centre

Michigan

Mid-2006

Chevrolet SSR roadster assembly

398

Spring Hill Manufacturing Line 1

Tennessee

March 2007

Saturn ION sedan and coupe assembly

5,776

Doraville Assembly

Georgia

2008

Minivan assembly

3,076

Lansing Metal Center

Michigan

2006

Metal fabricating

1,398

Portland Distribution Center

Oregon

2006

Parts distribution

95

Saint Louis Distribution Center

Missouri

2006

Parts distribution

182

Pittsburgh Metal

Pennsylvania

2007

Metal fabricating

613

Ypsilanti Processing Center

Michigan

2007

Parts processing

278

Flint North 3800

Michigan

2008

Engines

2,677

[edit] See also

[edit] People

[edit] Books and films

  • Final Offer - A documentary film that shows the 1984 GM contract negotiations, that would result in the union split of the Canadian arm of the UAW. A very interesting inside look at union negotiations.
  • Roger & Me - the first documentary by filmmaker Michael Moore. The film criticizes General Motors for closing down its factories in Moore's hometown of Flint, Michigan, despite record profits. After Flint residents lose their many jobs at GM, Moore claims the town descends into economic chaos.
  • Who Killed the Electric Car? - A documentary film charting GM's launch, then alleged self-sabotage of the electric car EV1.

[edit] Brands

(*) Signifies the brand is active

[edit] Other related topics

[edit] Subsidiaries

[edit] Divisions

[edit] Umbrella organization

[edit] Categories

[edit] References

1. ^ General Motors Corporate Information. Retrieved on July 22, 2007.

2. ^ General Motors Corporation Annual Report

3. ^ General Motors Corporation Annual Report

4. ^ Toyota slips behind GM in second quarter. MSNBC. Retrieved on July 20, 2007.

5. ^ $116 million PACE gift puts Purdue students in drivers' seat (September 26, 2006) Purdue News. Retrieved on May 8, 2007.

6. ^ [https://www.uawgmjas.org/j/index.php?option=com_frontpage&Itemid=1 "Welcome to the UAW-GM Center for Human Resources". UAW-GM Joint Activity System. Retrieved on June 19, 2007.

7. ^ Sloan, Allan (April 10, 2007).GM's High-Performance Pension Machine Washington Post, D02.

8. ^ GM becomes top-selling foreign automaker in China. Detroit News. Retrieved on April 10, 2007.

9. ^ Lindorff, Dave (April 19, 2005).Health Care Costs and the Jobs Flight to Canada Counterpunch. Retrieved on April 24, 2007.

10. ^ (10 Jan 2000) "D/C leaves lobby group (Auto news: digest)". Automotive News 74: 4.

11. ^ (July/Aug 2003) "Arctic Mayhem, Contrails and Climate, and Dirty Diesels". E Magazine: The Environmental Magazine 14: 64.

12. ^ http://www.kpcnews.com/articles/2007/07/27/greater_fort_wayne/news/doc46a9e1f76229a445366384.txt

13. ^ Political Economy Research Institute

14. ^ EPA document archived by Center for Public Integrity

15. ^ Center for Public Integrity file on GM

16. ^ GM's Hybrid Propulsion System for Transit Buses. Retrieved on 2007-05-22.

17. ^ GM steps up work on hydrogen cars TOM KRISHER, June 15, 2007, Business Week

18. ^ Sloan, Allan (April 10, 2007).GM's High-Performance Pension Machine Washington Post, D02.

19. ^ article. Detroit Free Press. Retrieved on March 23, 2006.

20. ^ GM sells Isuzu shares for $300 million. Detroit News. Retrieved on 2006-04-12.

[edit] Further reading

  • Barabba, Vincent P. Surviving Transformation: Lessons from GM's Surprising Turnaround (2004)
  • Chandler, Alfred D., Jr., ed. Giant Enterprise: Ford, General Motors, and the Automobile Industry 1964.
  • Cray, Ed. Chrome Colossus: General Motors and Its Times. 1980.
  • Farber, David. Sloan Rules: Alfred P. Sloan and the Triumph of General Motors U of Chicago Press 2002
  • Gustin, Lawrence R. Billy Durant: Creator of General Motors , 1973.
  • Halberstam, David. The Reckoning (1986) detailed reporting on the crises of 1973-mid 1980s
  • Keller, Maryann. Rude Awakening: The Rise, Fall, and Struggle for Recovery of General Motors, 1989.
  • Leslie, Stuart W. Boss Kettering: Wizard of General Motors Columbia University Press, 1983.
  • Maxton, Graeme P. and John Wormald, Time for a Model Change: Re-engineering the Global Automotive Industry (2004)
  • Maynard, Micheline. The End of Detroit: How the Big Three Lost Their Grip on the American Car Market (2003)
  • Rae, John B. The American Automobile: A Brief History. University of Chicago Press, 1965.
  • Sloan, Alfred P., Jr. My Years with General Motors, 1963.
  • Weisberger, Bernard A. The Dream Maker: William C. Durant, Founder of General Motors , 1979

Saturday, September 1, 2007

वाल्मीकि-रामायण कम्प्यूटर की कसौटी पर !
श्री राम के जन्म के विषय में विभिन्न धारणायें प्रचलित हैं। आधुनिक कम्प्यूटर युगीन विद्वानों को छोड़ कर लगभग सभी धर्मनिष्ठ व्यक्ति, ‘रामचरित मानस’ के रचयिता तुलसीदास, ‘रामायण’ के रचयिता आदि कवि वाल्मीकि तथा पुराण आदि इस बात में एक-सम्मत हैं कि श्री राम त्रेता युग में अवतरित हुए थे। त्रेता युग कितना पुरातन है, यह जानने के लिये अन्य युगों की जानकारी असंगत नहीं होगी। चार युगों की अवधि इस प्रकार मानी गई हैः सत्ययुगः १,७२८,०००(1,728,000) वर्ष; त्रेतायुगः १,२९६,०००(1,296,000) वर्ष; द्वापरयुगः ८६४,०००(864,000) वर्ष; कलियुगः ४३,२००० वर्ष कलियुग अभी अपने शैशव काल में ही है और केवल ५००६(5006) वर्ष ही लांघ कर वर्तमान में अपने रंग दिखा रहा है। इन आंकड़ों के आधार पर त्रेतायुग आज से ९२,५०६(92,506) वर्ष पहले समाप्त हुआ और श्री राम ने भी ९२,५०६(92,506) वर्ष पूर्व ही जन्म लिया होगा। यह काल भी निर्णयात्मक रूप से नहीं कहा जा सकता क्योंकि ‘मत्स्य पुराण’ के अनुसार रामायण-काल की घटनाएं २४वें ‘महायुग’ में निर्धारित की गई हैं। उक्त चारों युगों की आयु के योग को एक महायुग माना गया है, जिसका अर्थ है किः १ महायुग (१७२,८००० + १,२९६,००० + ८६४,००० + ४३,२०००) = ४,३२०,००० {(172,8000+1,296,000+864,000+43,2000)=4,320,000)}वर्ष का हुआ। यह ज्ञात होना आवश्यक है कि वर्तमान २८वां(28th) महायुग चल रहा है। ‘मत्स्य पुराण’ के अनुसार राम-काल से अब तक ४ युग व्यतीत हो चुके हैं। स्पष्ट है, राम के जीवनकाल को लगभग ४ x ४,३२०,००० = १७,२८०,००० (4×4,320,000=17,280,000)वर्ष बीत गये हैं। इसी भूलभुलैय्या में एक भटकी हुई धारणा के अनुसार राम-जन्म का समय १७८१२ (17812) वर्ष पूर्व बताया गया है। डा. प.व. वर्तक रामायाण काल को ७३२३ ईस्वी.पूर्व मानते हैं। यदि अपने स्थानीय छोटे से मन्दिर के पुजारी से पूछें तो वे अटपटा सा उत्तर दे कर विषय को समाप्त करने का प्रयत्न करेंगेः अजी, दस हजार से अधिक बात है किन्तु वैसे तो भगवान श्री राम जी अनादि हैं, अनन्त हैं। उनका आदि तथा अन्त के पूछने से भी पाप लगता है। ‘जय सिया राम’ कहो भाई!! प्रश्न है कि क्या इन में कोई भी प्रमाण मिलता है। उत्तर सीधा सा हैः ‘ नहीं! इन में कोई भी तर्कयुक्त अनुसंधानिक प्रमाण दिखाई नहीं देता। इन चार युगों और महा-युगों से थोड़ा निकल कर, आज के विज्ञान और आधुनिक कम्प्यूटर के युग में इसी विषय पर श्री पुष्कर भटनागर के शोध-कार्य पर दृष्टि डालें तो एक नई दिशा मिलती है। पुष्कर जी भारत में इन्लैंड रेवेन्यु विभाग में कार्य-रत हैं। उनके इस आश्चर्य-करने वाली खोज का ऋषि वाल्मीकि और उनकी रामायण से सीधा सम्बन्ध है। यह कहना उचित होगा कि वाल्मीकि स्वयं गणित-ज्योतिष, वेदांग-ज्योतिष विद्या, आकाशीय चन्द्र, सूर्य आदि नक्षत्रों और ग्रहों की गातियां तथा उनके काल-विभाजन का ज्ञान और खगोल विज्ञान के प्रकाण्ड पण्डित थे। इस ज्ञान का उन्होंने रामायण की रचना में बड़ी निपुणता से अपनी काव्य-कला में उपयोग किया है। वाल्मीकि श्री राम के समकालीन थे तथा उनकी जीवन घटनाओं से पूर्णरूपेन परिचित थे। कुछ लगों का कहना है कि राजाओं में अपनी जीवनी राज कवियों द्वारा लिखवाने का पुराना प्रचलन है जिसमें तथ्यों को दबा कर राजा के आदर्शों को उभारने के लिये आद्यंत अतिशयोक्ति का प्रयोग किया जाता था। किन्तु वाल्मीकि की रामायण के विषय में यह लागू नहीं होता क्योंकि वे ना तो राज-कवि थे और ना ही राज्य-ॠषि अथवा राज्य-गुरु थे। उनका अपना आश्रम था जिसे वे स्वाधीनता से चलाते थे। राजा से त्यक्त सीता को आश्रय देना इस का प्रमाण है। इस लिये रामायण में जो भी अतिरंजित भाग मिलता है, वह काव्य-कला के अनुरूप मान्य है। पुष्कर भटनागर जी के प्रयास से उन्हें अमेरिका से एक कम्प्यूटर सॉफ्टवेयर “प्लैनिटेरियम” प्राप्त हुआ। इस सॉफ्टवेयर से सूर्य, चन्द्र, ग्रहण, नक्षत्रों और ग्रहों की स्थिति, दूरी, काल-समय आदि की जानकारी के लिये खगोल तथा अन्य सम्बन्धित वैज्ञानिक, अन्तरिक्ष-जिज्ञासु आदि इस सॉफ्टवेयर का प्रयोग करते हैं। पुष्कर जी ने इस सॉफ्ट्वेयर फलस्वरूप रामायण की घटनाओं की सार्थकता की जांच की है। इस दिशा में उनके शोध-कार्य की सफलता के कुछ नमूने निम्नलिखित हैं -
१). श्री राम का जन्मः-रामायण के बाल-काण्ड के १९वें सर्ग तथा ८वें और ९वें श्लोक में स्पष्ट रूप से कहा है कि श्री राम का जन्म चैत्र मास की नवम तिथि में हुआ था जिस में राशि-चक्र और नक्षत्र मण्डल की स्थिति ऐसी थी कि सूर्य मेष घर में, शनि तुला में, बृहस्पति कर्क में, शुक्र शनि में, मंगल ग्रह मकर में थे।चैत्र मास के शुक्ल पक्ष के नवम दिवस तथा कर्क लग्न में जब कर्क पूर्व में उदय हो रहा था, चन्द्रमा पुनर्वासु (पोलक्स स्टार) पर और दिन में लगभग दोपहर का समय था। ये आंकड़े ‘प्लैनिटेरियम’ में कम्प्यूटर द्वारा भर दिये गए। कम्प्यूटर के परिणामों ने चकित कर दिया। राशि, नक्षत्र, ग्रहों तथा तारा-मण्डल की स्थिति से सिद्ध हुआ कि श्री राम का जन्म १० जनवरी, ५११४ (10 January, 5114) ईसवी पूर्व जो भारतीय पञ्चांग के अनुसार चैत्र मास के शुक्ल पक्ष की नवमी के दोपहर के १२ (12)बजे और १ (1) बजे के मध्य का समय निकलता है। इस प्रकार श्री राम का जन्म लगभग ७१२० (7120) वर्ष पूर्व हुआ था।श्री राम अनुज लक्षमण को ले कर १३वें (13th) वर्ष में ऋषि विश्वमित्र के साथ तपोवन में गये थे। वहां से राजा जनक की राजधानी मिथिला में प्रवेश किया जहां राजकुमारी सीता के साथ उनका विवाह सम्पन्न हुआ। वाल्मीकि ने इस यात्रा-मार्ग में २३ (23) स्थानों का उल्लेख किया है जिन में शृंगी आश्रम, राम घाट, ताड़का वन, सिद्धाश्रम, गौतमाश्रम, जनक पुर, सीता कुण्ड आदि सम्मलित हैं जहां आज भी उनके स्मारक-चिन्ह मिलते हैं। यह याद रहे कि स्थानों का नामकरण उन घटनाओं के पश्चात ही किया जाता है।
२). राम-बनवासः-अयोध्या काण्ड २।४।१८ (2/4/18) में स्पष्ट है कि राजा दशरथ ने राम के राज्याभिषेक का समय विद्वान पण्डितों तथा गुरु वसिष्ठ के निर्देशानुसार निश्चित किया था जिस समय सूर्य, चन्द्रमा और राहू राजा के रेवती नक्षत्र को इस प्रकार घेरे हुए थे जिस स्थिति में वे मृत्यु को प्राप्त होते हैं या षड़यन्त्र के शिकार होते हैं।राजा दशरथ की राशि मीन थी और नक्षत्र रेवती था। यही वह क्षण थे जब षड़यन्त्र द्वारा श्री राम को अयोध्या छोड़ कर १४ वर्ष का बनवास मिला। रामायण के अनुसार उस समय श्री राम की आयु २५ वर्ष थी। प्लैनिटेरियम सॉफ्टवेयर द्वारा इन आंकड़ों से सिद्ध होता है उस दिवस की तिथि ५ जनवरी ५०८९ ईसवी पूर्व (5 January 50890 ईसवी पूर्व तक २५ वर्ष ५ दिन(25 yrs. 5 days) बनते हैं जो वाल्मीकि के कथन की भी पुष्टि करती है।
३). खरदूषण से युद्धः-श्री राम के वनवास-काल के १३वें वर्ष के मध्य खरदूषण से उनका युद्ध हुआ था। उस समय रामायण में सूर्य-ग्रहण का उल्लेख मिलता है। वाल्मीकि यह भी लिखते हैं कि वह अमावस्य का दिन था तथा मंगल मध्य में था। एक ओर शुक्र एवं बुद्ध और दूसरी ओर सूर्य एवं शनि थे। कम्प्यूटर में यह आधार-सामग्री डालने पर परिणाम-स्वरूप ७ अक्तूबर, ५०७७ ई.पूर्व (7 October, 5077 ईसवी पूर्व) की तिथि प्राप्त हुई। साथ ही सूर्य ग्रहण और अमावस्या की स्थिति भी स्पष्ट थी। इतना ही नहीं बल्कि सूर्य-ग्रहण की दिशा भी मिलती है कि उस समय सूर्य ग्रहण पञ्चवटी से देखा जा सकता था।
४). रावण का वधः- रामायण में रावण के वध के समय नक्षत्रों की स्थिति वर्णन की गई है। इस आधार पर ‘प्लैनिटेरियम’ के अनुसार रावण की मृत्यु ४ दिसम्बर, ५०७६ (4 December, 5076) ईसवी पूर्व को हुई थी।
५). वन-वास की समाप्तिः-वन-वास की १४ (14) वर्षीय अवधि चैत्र मास के शुक्ल पक्ष की नवमी पर समाप्त होती है जो कम्प्यूटर के अनुसार २ जनवरी, ५०७५(2nd January, 5075) ईस्वी पूर्व थी। इस प्रकार अयोध्या लौटने के समय श्री राम की आयु ३९ वर्ष (39 years) की थी। इन सभी घटनाओं को अंक-गणित द्वारा परखें तो हर प्रकार से ताल-मेल ठीक बैठता है।‘प्लैनिटेरियम’ के अतिरिक्त और भी बातें हैं जो रामायण की अन्य घटनाओं और स्थान आदि पर भी दृष्टि डालना असंगत नहीं होगा।
६). समुद्र पर सेतु का निर्माणः-श्री राम की प्रेरणा से नल और नील अभियन्ताओं के पर्यवेक्षण में हनुमान आदि कुशल कार्य-कर्ताओं के प्रयास से सेतु-निर्माण का कार्य सम्पन्न हुआ था। एक अमेरिकन कम्पनी ने, जो समुद्री अन्वेषण के लिये कार्य कर रही है, इन्टरनेट पर कुछ मानव-कृत सेतु के चित्र दिये थे जिन में एक चाप आकार के पुल के अवशेष मन्नर खाड़ी में रामेश्वरम् तथा श्री लंका के मध्य डूबे हुए हैं। जिन पत्थरों का इस पुल में प्रयोग किया गया था, अनुमान है कि वे लगभग १,७००,००० वर्ष (1,700,000 yrs) पुराने थे। यह पुल कब बना था, इसके निर्माण-समय का अनुमान सन्देहात्मक है।
ऋषि वाल्मीकि के लिये दो शब्दः-कहा जाता है कि आरम्भ में वे दस्यु थे। अतः निर्भीकता का गुण उन में स्वतः ही आ गया था। जब उन्हें जीवन की सार्थकता का भान हुआ तो हृदय-परिवर्तन के साथ उचित-अनुचित का भेद समझ कर सत्य का साथ देते, चाहे राजा की अवज्ञा ही न करनी पड़े।राजा राम की त्याज्य गर्भवती सीता को बनैले पशुओं के मध्य वन में अकेली छोड़ दी गई, किन्तु किसी में भी साहस न था कि राजा के विरुद्ध उन्हें आश्रय दे दे। राजा से दण्डित प्राणी को, चाहे वह निर्दोष हो, शरण देने में किस का साहस था। वाल्मीकि ने औचित्य को वरीयता दे कर, सीता जी को केवल आश्रय ही नहीं दिया, उनको पुत्री कह कर सम्मानित किया। प्रत्यक्ष है कि वे समय से बहुत आगे थे। स्वयं निम्न जाति (दस्यु) के हो कर भी कर्म-परिवर्तन के आधार पर ऋषि-पद के स्तर को प्राप्त कर समाज की पुरानी धारणायें बदलने में सक्षम हुए। वे सच्चे रूप में क्रांतिकारी थे।महावीर शर्मा

श्री राम जय राम जय जय राम

वाल्मीकि-रामायण कम्प्यूटर की कसौटी पर !
श्री राम के जन्म के विषय में विभिन्न धारणायें प्रचलित हैं। आधुनिक कम्प्यूटर युगीन विद्वानों को छोड़ कर लगभग सभी धर्मनिष्ठ व्यक्ति, ‘रामचरित मानस’ के रचयिता तुलसीदास, ‘रामायण’ के रचयिता आदि कवि वाल्मीकि तथा पुराण आदि इस बात में एक-सम्मत हैं कि श्री राम त्रेता युग में अवतरित हुए थे। त्रेता युग कितना पुरातन है, यह जानने के लिये अन्य युगों की जानकारी असंगत नहीं होगी। चार युगों की अवधि इस प्रकार मानी गई हैः सत्ययुगः १,७२८,०००(1,728,000) वर्ष; त्रेतायुगः १,२९६,०००(1,296,000) वर्ष; द्वापरयुगः ८६४,०००(864,000) वर्ष; कलियुगः ४३,२००० वर्ष कलियुग अभी अपने शैशव काल में ही है और केवल ५००६(5006) वर्ष ही लांघ कर वर्तमान में अपने रंग दिखा रहा है। इन आंकड़ों के आधार पर त्रेतायुग आज से ९२,५०६(92,506) वर्ष पहले समाप्त हुआ और श्री राम ने भी ९२,५०६(92,506) वर्ष पूर्व ही जन्म लिया होगा। यह काल भी निर्णयात्मक रूप से नहीं कहा जा सकता क्योंकि ‘मत्स्य पुराण’ के अनुसार रामायण-काल की घटनाएं २४वें ‘महायुग’ में निर्धारित की गई हैं। उक्त चारों युगों की आयु के योग को एक महायुग माना गया है, जिसका अर्थ है किः १ महायुग (१७२,८००० + १,२९६,००० + ८६४,००० + ४३,२०००) = ४,३२०,००० {(172,8000+1,296,000+864,000+43,2000)=4,320,000)}वर्ष का हुआ। यह ज्ञात होना आवश्यक है कि वर्तमान २८वां(28th) महायुग चल रहा है। ‘मत्स्य पुराण’ के अनुसार राम-काल से अब तक ४ युग व्यतीत हो चुके हैं। स्पष्ट है, राम के जीवनकाल को लगभग ४ x ४,३२०,००० = १७,२८०,००० (4×4,320,000=17,280,000)वर्ष बीत गये हैं। इसी भूलभुलैय्या में एक भटकी हुई धारणा के अनुसार राम-जन्म का समय १७८१२ (17812) वर्ष पूर्व बताया गया है। डा. प.व. वर्तक रामायाण काल को ७३२३ ईस्वी.पूर्व मानते हैं। यदि अपने स्थानीय छोटे से मन्दिर के पुजारी से पूछें तो वे अटपटा सा उत्तर दे कर विषय को समाप्त करने का प्रयत्न करेंगेः अजी, दस हजार से अधिक बात है किन्तु वैसे तो भगवान श्री राम जी अनादि हैं, अनन्त हैं। उनका आदि तथा अन्त के पूछने से भी पाप लगता है। ‘जय सिया राम’ कहो भाई!! प्रश्न है कि क्या इन में कोई भी प्रमाण मिलता है। उत्तर सीधा सा हैः ‘ नहीं! इन में कोई भी तर्कयुक्त अनुसंधानिक प्रमाण दिखाई नहीं देता। इन चार युगों और महा-युगों से थोड़ा निकल कर, आज के विज्ञान और आधुनिक कम्प्यूटर के युग में इसी विषय पर श्री पुष्कर भटनागर के शोध-कार्य पर दृष्टि डालें तो एक नई दिशा मिलती है। पुष्कर जी भारत में इन्लैंड रेवेन्यु विभाग में कार्य-रत हैं। उनके इस आश्चर्य-करने वाली खोज का ऋषि वाल्मीकि और उनकी रामायण से सीधा सम्बन्ध है। यह कहना उचित होगा कि वाल्मीकि स्वयं गणित-ज्योतिष, वेदांग-ज्योतिष विद्या, आकाशीय चन्द्र, सूर्य आदि नक्षत्रों और ग्रहों की गातियां तथा उनके काल-विभाजन का ज्ञान और खगोल विज्ञान के प्रकाण्ड पण्डित थे। इस ज्ञान का उन्होंने रामायण की रचना में बड़ी निपुणता से अपनी काव्य-कला में उपयोग किया है। वाल्मीकि श्री राम के समकालीन थे तथा उनकी जीवन घटनाओं से पूर्णरूपेन परिचित थे। कुछ लगों का कहना है कि राजाओं में अपनी जीवनी राज कवियों द्वारा लिखवाने का पुराना प्रचलन है जिसमें तथ्यों को दबा कर राजा के आदर्शों को उभारने के लिये आद्यंत अतिशयोक्ति का प्रयोग किया जाता था। किन्तु वाल्मीकि की रामायण के विषय में यह लागू नहीं होता क्योंकि वे ना तो राज-कवि थे और ना ही राज्य-ॠषि अथवा राज्य-गुरु थे। उनका अपना आश्रम था जिसे वे स्वाधीनता से चलाते थे। राजा से त्यक्त सीता को आश्रय देना इस का प्रमाण है। इस लिये रामायण में जो भी अतिरंजित भाग मिलता है, वह काव्य-कला के अनुरूप मान्य है। पुष्कर भटनागर जी के प्रयास से उन्हें अमेरिका से एक कम्प्यूटर सॉफ्टवेयर “प्लैनिटेरियम” प्राप्त हुआ। इस सॉफ्टवेयर से सूर्य, चन्द्र, ग्रहण, नक्षत्रों और ग्रहों की स्थिति, दूरी, काल-समय आदि की जानकारी के लिये खगोल तथा अन्य सम्बन्धित वैज्ञानिक, अन्तरिक्ष-जिज्ञासु आदि इस सॉफ्टवेयर का प्रयोग करते हैं। पुष्कर जी ने इस सॉफ्ट्वेयर फलस्वरूप रामायण की घटनाओं की सार्थकता की जांच की है। इस दिशा में उनके शोध-कार्य की सफलता के कुछ नमूने निम्नलिखित हैं -
१). श्री राम का जन्मः-रामायण के बाल-काण्ड के १९वें सर्ग तथा ८वें और ९वें श्लोक में स्पष्ट रूप से कहा है कि श्री राम का जन्म चैत्र मास की नवम तिथि में हुआ था जिस में राशि-चक्र और नक्षत्र मण्डल की स्थिति ऐसी थी कि सूर्य मेष घर में, शनि तुला में, बृहस्पति कर्क में, शुक्र शनि में, मंगल ग्रह मकर में थे।चैत्र मास के शुक्ल पक्ष के नवम दिवस तथा कर्क लग्न में जब कर्क पूर्व में उदय हो रहा था, चन्द्रमा पुनर्वासु (पोलक्स स्टार) पर और दिन में लगभग दोपहर का समय था। ये आंकड़े ‘प्लैनिटेरियम’ में कम्प्यूटर द्वारा भर दिये गए। कम्प्यूटर के परिणामों ने चकित कर दिया। राशि, नक्षत्र, ग्रहों तथा तारा-मण्डल की स्थिति से सिद्ध हुआ कि श्री राम का जन्म १० जनवरी, ५११४ (10 January, 5114) ईसवी पूर्व जो भारतीय पञ्चांग के अनुसार चैत्र मास के शुक्ल पक्ष की नवमी के दोपहर के १२ (12)बजे और १ (1) बजे के मध्य का समय निकलता है। इस प्रकार श्री राम का जन्म लगभग ७१२० (7120) वर्ष पूर्व हुआ था।श्री राम अनुज लक्षमण को ले कर १३वें (13th) वर्ष में ऋषि विश्वमित्र के साथ तपोवन में गये थे। वहां से राजा जनक की राजधानी मिथिला में प्रवेश किया जहां राजकुमारी सीता के साथ उनका विवाह सम्पन्न हुआ। वाल्मीकि ने इस यात्रा-मार्ग में २३ (23) स्थानों का उल्लेख किया है जिन में शृंगी आश्रम, राम घाट, ताड़का वन, सिद्धाश्रम, गौतमाश्रम, जनक पुर, सीता कुण्ड आदि सम्मलित हैं जहां आज भी उनके स्मारक-चिन्ह मिलते हैं। यह याद रहे कि स्थानों का नामकरण उन घटनाओं के पश्चात ही किया जाता है।
२). राम-बनवासः-अयोध्या काण्ड २।४।१८ (2/4/18) में स्पष्ट है कि राजा दशरथ ने राम के राज्याभिषेक का समय विद्वान पण्डितों तथा गुरु वसिष्ठ के निर्देशानुसार निश्चित किया था जिस समय सूर्य, चन्द्रमा और राहू राजा के रेवती नक्षत्र को इस प्रकार घेरे हुए थे जिस स्थिति में वे मृत्यु को प्राप्त होते हैं या षड़यन्त्र के शिकार होते हैं।राजा दशरथ की राशि मीन थी और नक्षत्र रेवती था। यही वह क्षण थे जब षड़यन्त्र द्वारा श्री राम को अयोध्या छोड़ कर १४ वर्ष का बनवास मिला। रामायण के अनुसार उस समय श्री राम की आयु २५ वर्ष थी। प्लैनिटेरियम सॉफ्टवेयर द्वारा इन आंकड़ों से सिद्ध होता है उस दिवस की तिथि ५ जनवरी ५०८९ ईसवी पूर्व (5 January 50890 ईसवी पूर्व तक २५ वर्ष ५ दिन(25 yrs. 5 days) बनते हैं जो वाल्मीकि के कथन की भी पुष्टि करती है।
३). खरदूषण से युद्धः-श्री राम के वनवास-काल के १३वें वर्ष के मध्य खरदूषण से उनका युद्ध हुआ था। उस समय रामायण में सूर्य-ग्रहण का उल्लेख मिलता है। वाल्मीकि यह भी लिखते हैं कि वह अमावस्य का दिन था तथा मंगल मध्य में था। एक ओर शुक्र एवं बुद्ध और दूसरी ओर सूर्य एवं शनि थे। कम्प्यूटर में यह आधार-सामग्री डालने पर परिणाम-स्वरूप ७ अक्तूबर, ५०७७ ई.पूर्व (7 October, 5077 ईसवी पूर्व) की तिथि प्राप्त हुई। साथ ही सूर्य ग्रहण और अमावस्या की स्थिति भी स्पष्ट थी। इतना ही नहीं बल्कि सूर्य-ग्रहण की दिशा भी मिलती है कि उस समय सूर्य ग्रहण पञ्चवटी से देखा जा सकता था।
४). रावण का वधः- रामायण में रावण के वध के समय नक्षत्रों की स्थिति वर्णन की गई है। इस आधार पर ‘प्लैनिटेरियम’ के अनुसार रावण की मृत्यु ४ दिसम्बर, ५०७६ (4 December, 5076) ईसवी पूर्व को हुई थी।
५). वन-वास की समाप्तिः-वन-वास की १४ (14) वर्षीय अवधि चैत्र मास के शुक्ल पक्ष की नवमी पर समाप्त होती है जो कम्प्यूटर के अनुसार २ जनवरी, ५०७५(2nd January, 5075) ईस्वी पूर्व थी। इस प्रकार अयोध्या लौटने के समय श्री राम की आयु ३९ वर्ष (39 years) की थी। इन सभी घटनाओं को अंक-गणित द्वारा परखें तो हर प्रकार से ताल-मेल ठीक बैठता है।‘प्लैनिटेरियम’ के अतिरिक्त और भी बातें हैं जो रामायण की अन्य घटनाओं और स्थान आदि पर भी दृष्टि डालना असंगत नहीं होगा।
६). समुद्र पर सेतु का निर्माणः-श्री राम की प्रेरणा से नल और नील अभियन्ताओं के पर्यवेक्षण में हनुमान आदि कुशल कार्य-कर्ताओं के प्रयास से सेतु-निर्माण का कार्य सम्पन्न हुआ था। एक अमेरिकन कम्पनी ने, जो समुद्री अन्वेषण के लिये कार्य कर रही है, इन्टरनेट पर कुछ मानव-कृत सेतु के चित्र दिये थे जिन में एक चाप आकार के पुल के अवशेष मन्नर खाड़ी में रामेश्वरम् तथा श्री लंका के मध्य डूबे हुए हैं। जिन पत्थरों का इस पुल में प्रयोग किया गया था, अनुमान है कि वे लगभग १,७००,००० वर्ष (1,700,000 yrs) पुराने थे। यह पुल कब बना था, इसके निर्माण-समय का अनुमान सन्देहात्मक है।
ऋषि वाल्मीकि के लिये दो शब्दः-कहा जाता है कि आरम्भ में वे दस्यु थे। अतः निर्भीकता का गुण उन में स्वतः ही आ गया था। जब उन्हें जीवन की सार्थकता का भान हुआ तो हृदय-परिवर्तन के साथ उचित-अनुचित का भेद समझ कर सत्य का साथ देते, चाहे राजा की अवज्ञा ही न करनी पड़े।राजा राम की त्याज्य गर्भवती सीता को बनैले पशुओं के मध्य वन में अकेली छोड़ दी गई, किन्तु किसी में भी साहस न था कि राजा के विरुद्ध उन्हें आश्रय दे दे। राजा से दण्डित प्राणी को, चाहे वह निर्दोष हो, शरण देने में किस का साहस था। वाल्मीकि ने औचित्य को वरीयता दे कर, सीता जी को केवल आश्रय ही नहीं दिया, उनको पुत्री कह कर सम्मानित किया। प्रत्यक्ष है कि वे समय से बहुत आगे थे। स्वयं निम्न जाति (दस्यु) के हो कर भी कर्म-परिवर्तन के आधार पर ऋषि-पद के स्तर को प्राप्त कर समाज की पुरानी धारणायें बदलने में सक्षम हुए। वे सच्चे रूप में क्रांतिकारी थे।महावीर शर्मा

Wednesday, August 29, 2007

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Tuesday, August 14, 2007

Wi-Max

Contents
1 Definitions of terms
1.1 802.16d
1.2 802.16e
1.3 Fixed WiMAX
1.4 Mobile WiMAX
2 Uses
2.1 Broadband access
2.1.1 Subscriber units
2.2 Mobile applications
3 Technical information
3.1 MAC layer/data link layer
3.2 Physical layer
3.3 Comparison with Wi-Fi
3.4 Spectrum allocation issues
3.4.1 Limitations
3.5 Silicon implementations
4 Standards
4.1 IEEE 802.16e-2005
4.2 WiBro
5 Associations
5.1 WiMAX Forum
5.2 WiMAX Spectrum Owners Alliance - WiSOA
6 Competing technologies
6.1 3G and 4G cellular phone Systems
6.1.1 Mobile Broadband Wireless Access
6.2 Internet-oriented systems
6.3 Comparison
7 Future development
8 Current deployments

Definitions of terms[1]
The terms "fixed WiMAX", "mobile WiMAX", "802.16d" and "802.16e" are frequently used incorrectly. Correct definitions are:

[edit] 802.16d
Strictly speaking, 802.16d has never existed as a standard. The standard is correctly called 802.16-2004. However, since this standard is frequently called 802.16d, that usage also takes place in this article to assist readability.

[edit] 802.16e
Just as 802.16d has never existed, a standard called 802.16e hasn't either. It's an amendment to 802.16-2004, so is not a standard in its own right. It's properly referred to as 802.16e-2005.

[edit] Fixed WiMAX
This is a phrase frequently used to refer to systems built using 802.16-2004 ('802.16d') as the air interface technology.

[edit] Mobile WiMAX
A phrase frequently used to refer to systems built using 802.16e-2005 as the air interface technology. "Mobile WiMAX" implementations are therefore frequently used to deliver pure fixed services.

[edit] Uses
The bandwidth and reach of WiMAX make it suitable for the following potential applications:
Connecting Wi-Fi
hotspots with each other and to other parts of the Internet.
Providing a wireless alternative to cable and
DSL for last mile (last km) broadband access.
Providing high-speed data and telecommunications services.
Providing a diverse source of Internet connectivity as part of a business continuity plan. That is, if a business has a fixed and a wireless Internet connection, especially from unrelated providers, they are unlikely to be affected by the same service outage.
Providing nomadic connectivity.

[edit] Broadband access
Many companies are closely examining WiMAX for "
last mile" connectivity at high data rates. The resulting competition may bring lower pricing for both home and business customers, or bring broadband access to places where it has been economically unavailable. Prior to WiMAX, many operators have been using proprietary fixed wireless technologies for broadband services.
WiMAX access was used to assist with communications in Aceh, Indonesia, after the
tsunami in December 2004. All communication infrastructures, other than HAM Radio in the area were destroyed making the survivors unable to communicate with people outside the disaster area and vice versa. WiMAX provided broadband access that helped regenerate communication to and from Aceh.

[edit] Subscriber units
WiMAX subscriber units are available in both indoor and outdoor versions from several manufacturers. Self-install indoor units are convenient, but radio losses mean that the subscriber must be significantly closer to the WiMAX base station than with professionally installed external units. As such, indoor installed units require a much higher infrastructure investment as well as operational cost (site lease, backhaul, maintenance) due to the high number of base stations required to cover a given area. Indoor units are comparable in size to a cable modem or DSL modem. Outdoor units are roughly the size of a laptop PC, and their installation is comparable to a residential satellite dish.
With the advent of mobility ("16e"), there is an increasing focus on portable units. This includes handsets (similar to cellular
smartphones) and PC peripherals (PC Cards or USB dongles). In addition, there is much emphasis from operators on consumer electronics devices (games terminals, MP3 players and the like); it is notable this is more similar to WiFi than 3G cellular technologies.

[edit] Mobile applications
Some cellular companies are evaluating WiMAX as a means of increasing bandwidth for a variety of data-intensive applications;
Sprint Nextel announced in mid-2006 that it would invest about US$ 3 billion in a WiMAX technology buildout over the next few years[2].
In line with these possible applications is the technology's ability to serve as a high bandwidth "
backhaul" for Internet or cellular phone traffic from remote areas back to an Internet backbone. Although the cost per user/point of WiMAX in a remote application will be higher, it is not limited to such applications, and may be an answer to reducing the cost of T1/E1 backhaul as well. Given the limited wired infrastructure in some developing countries, the costs to install a WiMAX station in conjunction with an existing cellular tower or even as a solitary hub are likely to be small in comparison to developing a wired solution. Areas of low population density and flat terrain are particularly suited to WiMAX and its range. For countries that have skipped wired infrastructure as a result of prohibitive costs and unsympathetic geography, WiMAX can enhance wireless infrastructure in an inexpensive, decentralized, deployment-friendly and effective manner.

[edit] Technical information
WiMAX is a term coined to describe standard, interoperable implementations of
IEEE 802.16 wireless networks, in a rather similar way to Wi-Fi being interoperable implementations of the IEEE 802.11 Wireless LAN standard. However, WiMAX is very different from Wi-Fi in the way it works.

[edit] MAC layer/data link layer
In Wi-Fi the
media access controller (MAC) uses contention access — all subscriber stations that wish to pass data through a wireless access point (AP) are competing for the AP's attention on a random interrupt basis. This can cause subscriber stations distant from the AP to be repeatedly interrupted by closer stations, greatly reducing their throughput. This makes services such as Voice over IP (VoIP) or IPTV, which depend on an essentially constant Quality of Service (QoS) depending on data rate and interruptibility, difficult to maintain for more than a few simultaneous users.
In contrast, the 802.16 MAC uses a
scheduling algorithm for which the subscriber station need compete once (for initial entry into the network). After that it is allocated an access slot by the base station. The time slot can enlarge and contract, but remains assigned to the subscriber station which means that other subscribers cannot use it. In addition to being stable under overload and over-subscription (unlike 802.11), the 802.16 scheduling algorithm can also be more bandwidth efficient. The scheduling algorithm also allows the base station to control QoS parameters by balancing the time-slot assignments among the application needs of the subscriber stations.

[edit] Physical layer
The original WiMAX standard (IEEE 802.16) specified WiMAX for the 10 to 66 GHz range. 802.16a, updated in 2004 to 802.16-2004, added specifications for the 2 to 11 GHz range. 802.16-2004 was updated to 802.16e in 2005 and uses
scalable orthogonal frequency-division multiple access (SOFDMA) as opposed to the OFDM version with 256 sub-carriers (of which 200 are used) in 802.16d. More advanced versions including 802.16e also bring Multiple Antenna Support through Multiple-input multiple-output communications (MIMO). This brings potential benefits in terms of coverage, self installation, power consumption, frequency re-use and bandwidth efficiency. 802.16e also adds a capability for full mobility support. The WiMAX certification allows vendors with 802.16d products to sell their equipment as WiMAX certified, thus ensuring a level of interoperability with other certified products, as long as they fit the same profile.
Most commercial interest is in the 802.16d and .16e standards, since the lower frequencies used in these variants suffer less from inherent signal
attenuation and therefore give improved range and in-building penetration. Already today, a number of networks throughout the World are in commercial operation using certified WiMAX equipment compliant with the 802.16d standard.

[edit] Comparison with Wi-Fi
Possibly due to the fact both WiMAX and Wi-Fi begin with the same two letters, and are based upon IEEE standards beginning with 802., and both have a connection to wireless connectivity and the Internet, comparisons and confusion between the two are frequent. Despite this, both standards are aimed at different applications.
WiMAX is a long range system, covering many kilometers, that uses licensed or unlicensed
spectrum to deliver a point-to-point connection to the Internet from an ISP to an end user. Different 802.16 standards provide different types of access, from mobile (analogous to access via a cellphone) to fixed (an alternative to wired access, where the end user's wireless termination point is fixed in location.)
Wi-Fi is a shorter range system, typically hundreds of meters, that uses unlicensed spectrum to provide access to a network, typically covering only the network operator's own property. Typically Wi-Fi is used by an end user to access their own network, which may or may not be connected to the Internet. If WiMAX provides services analogous to a cellphone, Wi-Fi is more analogous to a cordless phone.
WiMAX is highly scalable from what are called 'femto' scale remote stations to multi-sector 'maxi' scale base that handle complex tasks of management and mobile handoff functions and include MIMO-AAS smart antenna subsystems.
Due to the ease and low cost with which Wi-Fi can be deployed, it is sometimes used to provide Internet access to third parties within a single room or building available to the provider, sometimes informally, and sometimes as part of a business relationship. For example, many coffee shops, hotels, and transportation hubs contain Wi-Fi access points providing access to the Internet for patrons.

[edit] Spectrum allocation issues
The 802.16 specification applies across a wide swath of the
RF spectrum. However, specification is not the same as permission to use. There is no uniform global licensed spectrum for WiMAX. In the US, the biggest segment available is around 2.5 GHz[3], and is already assigned, primarily to Sprint Nextel and Clearwire. Elsewhere in the world, the most likely bands used will be around 3.5 GHz, 2.3/2.5 GHz, or 5 GHz, with 2.3/2.5 GHz probably being most important in Asia. Some countries in Asia like India, Vietnam and Indonesia will use 3.3 GHz.
Analogue TV bands may become available for WiMAX use, but await the complete rollout of
digital TV, and there will be other uses suggested for that spectrum. In the U.S. The FCC auction for this spectrum is scheduled for the end of 2007. EU commissioner Viviane Reding has suggested re-allocation of 500-800 Mhz spectrum for wireless communication, including WiMAX [1].
It seems likely that there will be several variants of 802.16, depending on local regulatory conditions and thus on which spectrum is used, even if everything but the underlying radio frequencies is the same. WiMAX equipment will not, therefore, be as portable as it might have been - perhaps even less so than WiFi, whose assigned channels in unlicensed spectrum vary little from jurisdiction to jurisdiction. Manufacturers are compelled to provide multi-spectrum devices that can be used across different regions and regulatory requirements. WISOA is an organization that promotes roaming among service providers. However, this is no different than current mobile phones with dual band, triband and even quadband capabilities. Equipment vendors have already announced the development of multiband subscriber units.
WiMAX profiles define channel size, TDD/FDD and other necessary attributes in order to have inter-operating products. The current fixed profiles define for both TDD and FDD profiles. At this point, all of the mobile profiles are TDD only. The fixed profiles have channel sizes of 3.5 MHz, 5 MHz, 7 MHz and 10 MHz. The mobile profiles are 5 MHz, 8.75 MHz and 10 MHz. (Note: the 802.16 standard allows far wider variety of channels, but only the above subsets are supported as WiMAX profiles).
A major trend in capabilities that mitigates concerns about homogeneous global spectrum is the increasing ability of multi-mode and multi-spectrum wireless ICs and antenna components. This provides a form of De facto deregulation of spectrum as multiple spectra can be aggregated via hardware. This trend has appeared in the cellular and now will advance in the field based on the WiMAX standard for wireless broadband. Keep in mind that this is the 1st broad standard for WWAN systems under which standard multi-mode silicon is being developed.
One of the significant advantages of advanced wireless systems such as WiMAX is
spectral efficiency. For example, 802.16-2004 (fixed) has a spectral efficiency of 3.7 bit/s/hertz. But all 3.5-4G wireless systems similarly offer spectral efficiencies that are within a few tenths of a percent. The more notable advantage comes from combining SOFDMA with smart antenna technologies. This multiplies the effective spectral efficiency through multiple reuse and smart network deployment topologies. The direct use of frequency domain organization simplifies designs using MIMO-AAS compared to CDMA/WCDMA methods, resulting in more effective systems.

[edit] Limitations
A commonly held misconception is that WiMAX will deliver 70
Mbit/s, over 30 miles (48 kilometers). Both of these qualities are true individually, given ideal circumstances, but they are not simultaneously true. WiMAX has some similarities to DSL in this respect, where one can either have high bandwidth or long reach, but not both simultaneously.
The nature of wireless communications dictates that the antenna design will have a substantial impact on what is achievable. Typically, Fixed WiMAX networks have a higher-gain directional antenna installed externally at the customer's premises which results in greatly increased range and throughput. Mobile WiMAX networks comprise mostly of indoor CPEs such as desktop modems, laptops with integrated Mobile WiMAX or other Mobile WiMAX devices. Mobile WiMAX devices typically have an antenna design which is of lower-gain by nature due to their inherent omni-directional (and portable) design. In practice this means that in a line-of-sight environment with a portable Mobile WiMAX CPE, symmetrical speeds of 10 Mbit/s at 10 km could be delivered, but in urban environments it is more likely that these devices will not have line-of-sight and therefore users may only receive 10 Mbit/s over 2 km. Higher-gain directional antennas can be used with a Mobile WiMAX network with range and throughput benefits but the obvious loss of practical mobility.
Like most wireless systems, available bandwidth is shared between users in a given radio sector, so performance could deteriorate in the case of many active users on a single sector, especially if proper capacity planning has not been undertaken. In practice, many users will have a range of 2-, 4-, 6-, 8-, 10- or 12 Mbit/s services and additional radio cards will be added to the base station to increase the capacity as required.
Because of this, various granular and distributed network architectures are being incorporated into WiMAX through independent development and within the 802.16j, mobile multi-hop relay (MMR) task group. This includes wireless mesh, grids, network remote station repeaters which can extend networks and connect to back-haul.

[edit] Silicon implementations
A critical requirement for the success of a new technology is the availability of low-cost chipsets and silicon implementations.
Intel is a leader in promoting WiMAX, and has developed its own chipset. However, it is notable that most of the major semiconductor companies have to date been more cautious of involvement and most of the solutions come from specialist smaller or start-up suppliers. For client-side these include Altair, Beceem, GCI, Runcom and a number of others. Both Sequans and Wavesat manufacture solutions for both clients and network while Picochip is focussed on WiMAX chipsets for basestations.

[edit] Standards
The current WiMAX incarnation, Mobile WiMAX, is based upon IEEE Std 802.16e-2005
[4], approved in December 2005. It is an amendment of IEEE Std 802.16-2004[5] and so the actual standard is 802.16-2004 as amended by 802.16e-2005 - the specifications need to be read together to understand them.
IEEE Std 802.16-2004 addresses only fixed systems. It replaced IEEE Standards 802.16-2001, 802.16c-2002, and 802.16a-2003.

[edit] IEEE 802.16e-2005
IEEE 802.16e-2005 improves upon IEEE 802.16-2004 by:
Scaling of the
Fast Fourier Transform (FFT) to the channel bandwidth in order to keep the carrier spacing constant across different channel bandwidths (1.25-20 MHz). Constant carrier spacing results in a higher spectrum efficiency in wide channels, and a cost reduction in narrow channels. Also known as Scalable OFDMA (SOFDMA).
Improving
NLOS coverage by utilizing advanced antenna diversity schemes, and hybrid-Automatic Retransmission Request (hARQ)
Improving capacity and coverage by introducing
Adaptive Antenna Systems (AAS) and Multiple Input Multiple Output (MIMO) technology
Increasing system gain by use of denser sub-channelization, thereby improving indoor penetration
Introducing high-performance coding techniques such as
Turbo Coding and Low-Density Parity Check (LDPC), enhancing security and NLOS performance
Introducing downlink sub-channelization, allowing administrators to trade coverage for capacity or vice versa
Enhanced Fast Fourier Transform algorithm can tolerate larger delay spreads, increasing resistance to
multipath interference
Adding an extra QoS class (enhanced real-time Polling Service) more appropriate for
VoIP applications.
Adding support for mobility (soft and hard handover between base stations). This is seen as one of the most important aspects of 802.16e-2005, and is the very basis of 'Mobile WiMAX'.
802.16d vendors point out that fixed WiMAX offers the benefit of available commercial products and implementations optimized for fixed access. It is a popular standard among alternative service providers and operators in developing areas due to its low cost of deployment and advanced performance in a fixed environment. Fixed WiMAX is also seen as a potential standard for backhaul of wireless base stations such as cellular, WiFi or even Mobile WiMAX.
SOFDMA (used in 802.16e-2005) and OFDM256 (802.16d) are not compatible so most equipment will have to be replaced if an operator wants or needs to move to the later standard. However, some manufacturers are planning to provide a migration path for older equipment to SOFDMA compatibility which would ease the transition for those networks which have already made the OFDM256 investment. This affects a relatively small number users and operators.

[edit] WiBro
South Korea's electronics and telecommunication industry spearheaded by Samsung Electronics and ETRI has developed its own standard, WiBro. In late 2004, Intel and LG Electronics have agreed on a merger of mobile WiBro(S-OFDMA modulation) and fixed WiMAX(OFDM modulation) to produce a new standard dubbed Mobile WiMax(802.16e-2005) combining features from both to avoid a future standard war. From this point on WiBro became a specific subset implementation of 802.16e-2005 standard over 8.75 Mhz channels in 2.3 Ghz band, whereas Mobile WiMax represents a full implementation of 802.16e-2005 standard that supports flexible channel size and service band. The side effect of this merger is that Mobile WiMax gears are backward compatible with WiBro gears but not with fixed WiMax gears, reflecting its WiBro originated heritage.
WiBro has South Korean government support with the requirement for each carrier to spend over US$1 billion for deployments. Korea sought to develop WiBro as a regional and potentially international alternative to 3.5G or 4G cellular systems. But given the lack of momentum as a standard, WiBro has joined WiMAX and agreed to harmonize with the similar OFDMA 802.16e version of the standard.
What makes WiBro roll-outs a good "test case" for the overall WiMAX effort is that it is mobile, well thought out for delivery of wireless broadband services, and the fact that the deployment is taking place in a highly sophisticated, broadband-saturated market. WiBro will go up against 3G and very high bandwidth wire-line services rather than as gap-filler or rural under-served market deployments often thought of as "best fit" markets for WiMAX.
As such, WiBRO is now best described as a particular profile within WiMAX with 8.75MHz channel in the 2.3GHz band.

[edit] Associations

[edit] WiMAX Forum

The WiMAX Forum is the organization dedicated to certifying the interoperability of WiMAX products. Those that pass conformance and interoperability testing achieve the "WiMAX Forum Certified" designation and can display this mark on their products and marketing materials. Some vendors claim that their equipment is "WiMAX-ready", "WiMAX-compliant", or "pre-WiMAX", if they are not officially WiMAX Forum Certified. [6]

[edit] WiMAX Spectrum Owners Alliance - WiSOA

WiSOA is the first global organization composed exclusively of owners of WiMAX spectrum without plans to deploy WiMAX technology in those bands. WiSOA is focussed on the regulation, commercialisation, and deployment of WiMAX spectrum in the 2.3–2.5 GHz and the 3.4–3.5 GHz ranges. WiSOA are dedicated to educating and informing its members, industry representatives and government regulators of the importance of WiMAX spectrum, its use, and the potential for WiMAX to revolutionise broadband.[7]

[edit] Competing technologies

Within the marketplace, WiMAX's main competition comes from existing widely deployed wireless systems such as UMTS and CDMA2000, as well as a number of Internet oriented systems such as HIPERMAN and WiBro.
[edit] 3G and 4G cellular phone Systems
Both of the two major
3G systems, CDMA2000 and UMTS, compete with WiMAX. Both aim to offer DSL-class Internet access in addition to phone service. UMTS has also been enhanced to compete directly with WiMAX in the form of UMTS-TDD, which can use WiMAX oriented spectrum and provides a more consistent, if lower bandwidth at peak, user experience than WiMAX.
3G cellular phone systems usually benefit from already having entrenched infrastructure, being upgraded from earlier systems. Users can usually fall back to older systems when they move out of range of upgraded equipment, often relatively seamlessly.
The major cellular standards are being evolved to so-called
4G, high bandwidth, low latency, all-IP networks with voice services built on top. With GSM/UMTS, the move to 4G is the 3GPP Long Term Evolution effort. For AMPS/TIA derived standards such as CDMA2000, a replacement called Ultra Mobile Broadband is under development. In both cases, existing air interfaces are being discarded, in favour of OFDMA for the downlink and a variety of OFDM based solutions for the uplink, much akin to WiMAX.
In some areas of the world the wide availability of UMTS and a general desire for standardization has meant spectrum has not been allocated for WiMAX: in July 2005, the
EU-wide frequency allocation for WiMAX was blocked.

[edit] Mobile Broadband Wireless Access
Mobile Broadband Wireless Access (MBWA) is a technology being developed by
IEEE 802.20 and is aimed at wireless mobile broadband for operations from 120 to 350 km/h. The 802.20 standard has taken on many of the methods behind Mobile WiMAX, including high speed dynamic modulation and similar scalable OFDMA capabilities. It apparently retains fast hand-off, Forward Error Correction (FEC) and cell edge enhancements.
The Working Group was temporarily suspended in mid 2006 by the IEE-SA Standards Board since it had been the subject of a number of appeals, and a preliminary investigation of one of these "revealed a lack of transparency, possible 'dominance,' and other irregularities in the Working Group"
[8].
In September 2006 the IEE-SA Standards Board approved a plan to enable the working group to continue under new conditions, and the standard is now expected to be finalized by Q2 2008.

[edit] Internet-oriented systems
Early WirelessMAN standards, the European standard
HIPERMAN and Korean standard WiBro have been harmonized as part of WiMAX and are no longer seen as competition but as complementary. All networks now being deployed in South Korea, the home of the Wibro standard, are now WiMAX.
As a short-range mobile Internet solution, such as in cafes and at transportation hubs like airports, the popular
WiFi 802.11b/g system is widely deployed, and provides enough coverage for some users to feel subscription to a WiMAX service is unnecessary.
The following table should be treated with caution as it only shows peak rates which are potentially very misleading.

[edit] Comparison
Main article:
Comparison of wireless data standards
vde
Comparison of Mobile Internet Access methods
Standard
Family
Primary Use
Radio Tech
Downlink (Mbps)
Uplink (Mbps)
Notes
802.16e
WiMAX
Mobile Internet
MIMO-SOFDMA
70
70
Quoted speeds only achievable at very short ranges, more practically 10 Mbps at 10 km.
HIPERMAN
HIPERMAN
Mobile Internet
OFDM
56.9
56.9
WiBro
WiBro
Mobile Internet
OFDMA
50
50
Mobile range (900 m)
iBurst
iBurst 802.20
Mobile Internet
HC-SDMA
64
64
3-12 km
UMTS W-CDMAHSDPA+HSUPA
UMTS/3GSM
Mobile phone
CDMA/FDD
.38414.4
.3845.76
HSDPA widely deployed. Typical downlink rates today 1-2Mbps, ~200kbps uplink; future downlink up to 28.8Mbps.
UMTS-TDD
UMTS/3GSM
Mobile Internet
CDMA/TDD
16
16
Reported speeds according to
IPWireless using 16QAM modulation similar to HSDPA+HSUPA
LTE UMTS
UMTS/4GSM
General 4G
OFDMA/MIMO/SC-FDMA (HSOPA)
>100
>50
Still in development
1xRTT
CDMA2000
Mobile phone
CDMA
0.144
0.144
Obsoleted by EV-DO
EV-DO 1x Rev. 0EV-DO 1x Rev.AEV-DO Rev.B
CDMA2000
Mobile Internet
CDMA/FDD
2.453.14.9xN
0.151.81.8xN
Rev B note: N is the number of 1.25 MHz chunks of spectrum used. Not yet deployed.
Notes: All speeds are theoretical maximums and will vary by a number of factors, including the use of external antennae, distance from the tower and the ground speed (i.e. communications on a train may be poorer than when standing still.) Usually the bandwidth is shared between several terminals. The performance of each technology is determined by a number of constraints, including the
spectral efficiency of the technology, the cell sizes used, and the amount of spectrum available. For more information, see Comparison of wireless data standards.

Future development
Mobile WiMAX based upon 802.16e-2005 has been accepted as IP-OFDMA for inclusion as the sixth wireless link system under IMT-2000. This can hasten acceptance by regulatory authorities and operators for use in cellular spectrum. WiMAX II, 802.16m will be proposed for IMT-Advanced 4G.
The goal for the long term evolution of both WiMAX and LTE is to achieve 100 Mbit/s mobile and 1 Gbit/s fixed-nomadic bandwidth as set by ITU for 4G NGMN (Next Generation Mobile Network) systems through the adaptive use of MIMO-AAS and smart, granular network topologies. 3GPP LTE and WiMAX-m are concentrating much effort on MIMO-AAS, mobile multi-hop relay networking and related developments needed to deliver 10X and higher Co-Channel reuse multiples.
Since the evolution of core air-link technologies has approached the practical limits imposed by Shannon's Theorem, the evolution of wireless has embarked on pursuit of the 3X to 10X+ greater bandwidth and network efficiency gains that are expected by advances in the spatial and smart wireless broadband networking technologies. What will clearly define 4G more than either WCDMA or OFDMA wireless link methods will be wireless networks that more effectively adapt to and take advantage of available spectrum.

Current deployments
Main article: List of Deployed WiMAX networks(Country by Country List)
The WiMAX Forum now lists over 350 WiMAX trials and deployments. Current and planned deployments and the bands in which they operate and the standards they use are listed in the above article.

Monday, August 13, 2007

Wi-Fi

Wi-Fi is a wireless technology brand owned by the Wi-Fi Alliance intended to improve the interoperability of wireless local area network products based on the IEEE 802.11 standards.
Common applications for Wi-Fi include Interne and VoIP phone access,
gaming, and network connectivity for consumer electronics such as televisions, DVD players, and digital cameras.
Contents[
hide]
1 Definition
2 Uses
3 Advantages of Wi-Fi
4 Disadvantages of Wi-Fi
5 Standard Devices
6 Non-Standard Devices
6.1 Embedded systems
7 Unintended and intended use by outsiders
8 Wi-Fi vs. amateur radio
9 Media reports of health risks
10 History
11 Origin and meaning of the term "Wi-Fi"
//

[edit] Definition
Main article:
Wi-Fi Technical Information
According to the brand style guide of the Wi-Fi Alliance (the owner of the Wi-Fi brand):
"Products which successfully pass the Wi-Fi Alliance testing may use the Wi-Fi CERTIFIED brand. The Alliance tests and certifies the interoperability of wireless LAN products based on the
IEEE 802.11 standards. Studies show that 88% of consumers prefer products which have been tested by an independent organization."
Wi-Fi technologies have gone through several generations since their inception in 1997. Wi-Fi is supported to different extents under
Microsoft Windows, Apple Mac OS and open source Unix and Linux operating systems. Contrary to popular belief, Wi-Fi is not an abbreviation for "Wireless Fidelity" (see "Origin and meaning of the term "Wi-Fi"" below).

[edit] Uses
A Wi-Fi enabled device such as a PC,
cell phone or PDA can connect to the Internet when within range of a wireless network connected to the Internet. The area covered by one or several interconnected access points is called a hotspot. Hotspots can cover as little as a single room with wireless-opaque walls or as much as many square miles covered by overlapping access points. Wi-Fi can also be used to create a mesh network. Both architectures are used in community networks.[citation needed]
Wi-Fi also allows connectivity in
peer-to-peer (wireless ad-hoc network) mode, which enables devices to connect directly with each other. This connectivity mode is useful in consumer electronics and gaming applications.
When the technology was first commercialized there were many problems because consumers could not be sure that products from different vendors would work together. The Wi-Fi Alliance began as a community to solve this issue so as to address the needs of the end user and allow the technology to mature. The Alliance created the branding Wi-Fi CERTIFIED to show consumers that products are
interoperable with other products displaying the same branding.
Many consumer devices use Wi-Fi. Amongst others,
personal computers can network to each other and connect to the Internet, mobile computers can connect to the Internet from any Wi-Fi hotspot, and digital cameras can transfer images wirelessly.
Routers which incorporate a DSL or cable modem and a Wi-Fi access point are often used in homes and other premises, and provide Internet access and internetworking to all devices connected wirelessly or by cable into them. Devices supporting Wi-Fi can also be connected in ad-hoc mode for client-to-client connections without a router.
Business and industrial Wi-Fi is widespread as of 2007. In business environments, increasing the number of Wi-Fi access points provides redundancy, support for fast roaming and increased overall network capacity by using more channels or creating smaller cells. Wi-Fi enables wireless voice applications (VoWLAN or WVOIP). Over the years, Wi-Fi implementations have moved toward 'thin' access points, with more of the network intelligence housed in a centralized network appliance, relegating individual Access Points to be simply 'dumb' radios. Outdoor applications may utilize true
mesh topologies. As of 2007 Wi-Fi installations can provide a secure computer networking gateway, firewall, DHCP server, intrusion detection system, and other functions.
In addition to restricted use in homes and offices, Wi-Fi is publicly available at
Wi-Fi hotspots provided either free of charge or to subscribers to various providers. Free hotspots are often provided by businesses such as hotels, restaurants, and airports who offer the service to attract or assist clients. Sometimes free Wi-Fi is provided by enthusiasts, or by organisations or authorities who wish to promote business in their area. Metropolitan-wide WiFi (Mu-Fi) already has more than 300 projects in process.[1]

[edit] Advantages of Wi-Fi
Wi-Fi allows LANs to be deployed without cabling for client devices, typically reducing the costs of network deployment and expansion. Spaces where cables cannot be run, such as outdoor areas and historical buildings, can host wireless LANs.
As of 2007 wireless network adapters are built into most modern laptops. The price of
chipsets for Wi-Fi continues to drop, making it an economical networking option included in ever more devices. Wi-Fi has become widespread in corporate infrastructures, which also helps with the deployment of RFID technology that can piggyback on Wi-Fi [2].
Different competitive brands of access points and client network interfaces are inter-operable at a basic level of service. Products designated as "Wi-Fi Certified" by the Wi-Fi Alliance are backwards inter-operable. Wi-Fi is a global set of standards. Unlike
mobile telephones, any standard Wi-Fi device will work anywhere in the world.
Wi-Fi is widely available in more than 250,000 public hotspots and tens of millions of homes and corporate and university campuses worldwide.
WPA is not easily cracked if strong passwords are used and WPA2 encryption has no known weaknesses. New protocols for Quality of Service (WMM) make Wi-Fi more suitable for latency-sensitive applications (such as voice and video), and power saving mechanisms (WMM Power Save) improve battery operation.

[edit] Disadvantages of Wi-Fi
Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for an additional 2 channels beyond those permitted in the US (1-13 vs 1-11); Japan has one more on top of that (1-14), and some countries, like Spain, prohibit use of the lower-numbered channels. Europe, as of 2007, is now essentially homogeneous in this respect. Some countries, such as Italy, formerly required a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration.[
citation needed] Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm (0.1 W).
Power consumption is fairly high compared to some other low-bandwidth standards, such as
Zigbee and Bluetooth, making battery life a concern.
The most common wireless encryption standard,
Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an open (encryption-free) mode. Novice users benefit from a zero-configuration device that works out of the box, but without security enabled, providing open wireless access to their LAN. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI). Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. (HTTPS/Secure Socket Layer)
Many 2.4 GHz
802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain channels. To change the channel of operation for an access point requires the user to configure the device.
Wi-Fi networks have limited range. A typical Wi-Fi home router using
802.11b or 802.11g with a stock antenna might have a range of 45 m (150 ft) indoors and 90 m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor range with improved (directional) antennas can be several kilometres or more with line-of-sight.
Wi-Fi pollution, or an excessive number of access points in the area, especially on the same or neighboring channel, can prevent access and interfere with the use of other access points by others, caused by overlapping channels in the 802.11g/b spectrum, as well as with decreased
signal-to-noise ratio (SNR) between access points. This can be a problem in high-density areas, such as large apartment complexes or office buildings with many Wi-Fi access points. Additionally, other devices use the 2.4 GHz band: microwave ovens, cordless phones, baby monitors, security cameras, and Bluetooth devices can cause significant additional interference.
It is also an issue when municipalities
[3], or other large entities such as universities, seek to provide large area coverage. Everyone is considered equal for the base standard without 802.11e/WMM when they use the band. This openness is also important to the success and widespread use of 2.4 GHz Wi-Fi, but makes it unsuitable for "must-have" public service functions or where reliability is required.
Interoperability issues between brands or proprietary deviations from the standard can disrupt connections or lower throughput speeds on other user's devices that are within range. Additionally, Wi-Fi devices do not, as of 2007, pick channels to avoid interference.[
citation needed]

[edit] Standard Devices
Wireless access points connects a group of wireless devices to an adjacent wired LAN. An access point is similar to an ethernet hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an ethernet hub or switch, allowing wireless devices to communicate with other wired devices.
Wireless adapters allow devices to connect to a wireless network. These adapters connect to devices using various external or internal interconnects such as PCI, miniPCI, USB, ExpressCard, Cardbus and PC card. Most newer laptop computers are equipped with internal adapters. Internal cards are generally more difficult to install.
Wireless
routers integrate WAP, ethernet switch, and internal Router firmware application that provides IP Routing, NAT, and DNS forwarding through an integrated WAN interface. A wireless router allows wired and wireless ethernet LAN devices to connect to a (usually) single WAN device such as cable modem or DSL modem. A wireless router allows all three devices (mainly the access point and router) to be configured through one central utility. This utility is most usually an integrated web server which serves web pages to wired and wireless LAN clients and often optionally to WAN clients. This utility may also be an application that is run on a desktop computer such as Apple's AirPort.
Wireless
Ethernet bridges connect a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the data-link layer. Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.
Wireless range extenders or
wireless repeaters can extend the range of an existing wireless network. Range extenders can be strategically placed to elongate a signal area or allow for the signal area to reach around barriers such as those created in L-shaped corridors. Wireless devices connected through repeaters will suffer from an increased latency for each hop. Additionally, a wireless device at the end of chain of wireless repeaters will have a throughput that is limited by the weakest link within the repeater chain.
Most commercial devices (routers, access points, bridges, repeaters) designed for home or business environments use either
RP-SMA or RP-TNC antenna connectors. PCI wireless adapters also mainly use RP-SMA connectors. Most PC card and USB wireless only have internal antennas etched on their printed circuit board while some have MMCX connector or MC-Card external connections in addition to an internal antenna. A few USB cards have a RP-SMA connector. Most Mini PCI wireless cards utilize Hirose U.FL connectors, but cards found in various wireless appliances contain all of the connectors listed. Many high-gain (and homebuilt antennas) utilize the Type N connector more commonly used by other radio communications methods.

[edit] Non-Standard Devices
USB-Wi-Fi adapters, food container "
Cantennas", parabolic reflectors, and many other types of self-built antennae are increasingly made by do-it-yourselfers. For minimal budgets, as low as a few dollars, signal strength and range can be improved dramatically.
As of 2007,
Long Range Wi-Fi kits have begun to enter the market. Companies like BroadbandXpress offer long range, inexpensive kits that can be setup with limited knowledge. These kits utilize specialized antennas which increase the range of Wi-Fi dramatically, up to the world record 137.2 miles (220 km). These kits are commonly used to get broadband internet to a place without direct broadband access.[4]
The longest link ever achieved was by the Swedish space agency. They attained 310 km, but used 6 watt amplifiers to reach an overhead stratospheric balloon. [citation needed] The longest link without amplification was 279 km in Venezuela, 2006. [5]

Embedded systems
Wi-Fi availability in the home is on the increase. This extension of the Internet into the home space will increasingly be used for remote monitoring. Examples of remote monitoring include security systems and tele-medicine. In all these kinds of implementation, if the Wi-Fi provision is provided using a system running one of operating systems mentioned above, then it becomes unfeasible due to weight, power consumption and cost issues.
Increasingly in the last few years (particularly as of early 2007), embedded Wi-Fi modules have become available which come with a real-time operating system and provide a simple means of wireless enabling any device which has and communicates via a serial port.
This allows simple monitoring devices -- for example, a portable ECG monitor hooked up to a patient in their home -- to be created. This Wi-Fi enabled device effectively becomes part of the internet cloud and can communicate with any other node on the internet. The data collected can hop via the home's Wi-Fi access point to anywhere on the internet.
These Wi-Fi modules are designed so that minimal Wi-Fi knowledge is required by designers to wireless enable their product.

[edit] Unintended and intended use by outsiders

Wikinews has related news:
Florida man charged with stealing WiFi
Measures to deter unauthorized users include suppressing the AP's service set identifier (SSID) broadcast, allowing only computers with known MAC addresses to join the network, and various encryption standards. Access points and computers using no encryption are vulnerable to eavesdropping by an attacker armed with packet sniffer software. If the eavesdropper has the ability to change his MAC address then he can potentially join the network by spoofing an authorised address.
WEP encryption can protect against casual snooping but may also produce a misguided sense of security since freely available tools such as AirSnort can quickly recover WEP encryption keys. Once it has seen 5-10 million encrypted packets, AirSnort will determine the encryption password in under a second.[6] The newer Wi-Fi Protected Access (WPA) and IEEE 802.11i (WPA2) encyption standards do not have the serious weaknesses of WEP encryption, but require strong passphrases for full security.
Recreational exploration of other people's access points has become known as
wardriving, and the leaving of graffiti describing available services as warchalking. These activities may be illegal in certain jurisdictions, but existing legislation and case-law is often unclear.
However, it is also common for people to unintentionally use others' Wi-Fi networks without explicit authorization. Operating systems such as
Windows XP SP2 and Mac OS X automatically connect to an available wireless network, depending on the network configuration. A user who happens to start up a laptop in the vicinity of an access point may find the computer has joined the network without any visible indication. Moreover, a user intending to join one network may instead end up on another one if the latter's signal is stronger. In combination with automatic discovery of other network resources (see DHCP and Zeroconf) this could possibly lead wireless users to send sensitive data to the wrong destination. [citation needed]
In
Singapore, using another person's Wi-Fi network is illegal under the Computer Misuse Act. A 17 year old has been arrested for simply tapping into his neighbor's wireless Internet connection and faces up to 3 years' imprisonment and a fine.[7]

[edit] Wi-Fi vs. amateur radio
In the US, Canada and Australia, a portion of the 2.4 GHz Wi-Fi radio spectrum is also allocated to
amateur radio users. In the US, FCC Part 15 rules govern non-licensed operators (i.e. most Wi-Fi equipment users). Under Part 15 rules, non-licensed users must "accept" (i.e. endure) interference from licensed users and not cause harmful interference to licensed users. Amateur radio operators are licensed users, and retain what the FCC terms "primary status" on the band, under a distinct set of rules (Part 97). Under Part 97, licensed amateur operators may construct their own equipment, use very high-gain antennas, and boost output power to 100 watts on frequencies covered by Wi-Fi channels 2-6. However, Part 97 rules mandate using only the minimum power necessary for communications, forbid obscuring the data, and require station identification every 10 minutes. Therefore, output power control is required to meet regulations, and the transmission of any encrypted data (for example https) is questionable.
In practice, microwave power amplifiers are expensive. On the other hand, the short
wavelength at 2.4 GHz allows for simple construction of very high gain directional antennas. Although Part 15 rules forbid any modification of commercially constructed systems, amateur radio operators may modify commercial systems for optimized construction of long links, for example. Using only 200 mW link radios and high gain directional antennas, a very narrow beam may be used to construct reliable links with minimal radio frequency interference to other users.

[edit] Media reports of health risks
The
UK's Health Protection Agency considers there is no consistent evidence of harm from the low power transmissions of Wi-Fi equipment, nevertheless their chairman, Sir William Stewart, stated that it is a sensible precaution to keep the situation under review.[8] Two media items (the latest in an episode of the current affairs television program Panorama in May 2007) reported that schools and families have been removing their Wi-Fi systems as a result.[9] Individual anecdotes of deleterious effects which ceased upon removal of the systems have also been reported including headaches and lethargy.[9]. Consensus amongst scientists is that there is no evidence of harm, and the continuing calls for more research into the effects on human health remain limited. Thirty-seven studies have already been conducted that do not show a causal relationship.[9][10]

[edit] History
Wi-Fi uses both single carrier
direct-sequence spread spectrum radio technology (part of the larger family of spread spectrum systems) and multi-carrier OFDM (Orthogonal Frequency Division Multiplexing) radio technology. These regulations then enabled the development of Wi-Fi, its onetime competitor HomeRF, and Bluetooth.
Unlicensed spread spectrum was first made available by the
Federal Communications Commission in 1985 and these FCC regulations were later copied with some changes in many other countries enabling use of this technology in all major countries.[11] The FCC action was proposed by Michael Marcus of the FCC staff in 1980 and the subsequent controversial regulatory action took 5 more years. It was part of a broader proposal to allow civil use of spread spectrum technology and was opposed at the time by main stream equipment manufacturers and many radio system operators.
The precursor to Wi-Fi was invented in 1991 by
NCR Corporation/AT&T (later Lucent & Agere Systems) in Nieuwegein, the Netherlands. It was initially intended for cashier systems; the first wireless products were brought on the market under the name WaveLAN with speeds of 1 Mbit/s to 2 Mbit/s. Vic Hayes, who held the chair of IEEE 802.11 for 10 years and has been named the 'father of Wi-Fi,' was involved in designing standards such as IEEE 802.11b, 802.11a and 802.11g.

[edit] Origin and meaning of the term "Wi-Fi"
Despite the similarity between the terms "Wi-Fi" and "
Hi-Fi", statements reportedly made by Phil Belanger of the Wi-Fi Alliance contradict the popular conclusion that "Wi-Fi" stands for "Wireless Fidelity".[12] According to Mr Belanger, the Interbrand Corporation developed the brand "Wi-Fi" for the Wi-Fi Alliance to use to describe WLAN products that are based on the IEEE 802.11 standards. In Mr Belanger's words, "Wi-Fi and the yin yang style logo were invented by Interbrand. We [the founding members of the Wireless Ethernet Compatibility Alliance, now called the Wi-Fi Alliance] hired Interbrand to come up with the name and logo that we could use for our interoperability seal and marketing efforts. We needed something that was a little catchier than 'IEEE 802.11b Direct Sequence'."
थे wi-फि अलायंस themselves इन्वोकेद थे टर्म "वायरलेस फिदेलिटी" विथ थे मार्केटिंग ऑफ़ अ टैग लीन, "थे स्टैंडर्ड फ़ॉर वायरलेस फिदेलिटी", बुत लेटर रेमोवेद थे टैग फ्रॉम थेइर मार्केटिंग. थे wi-फि अलायंस नोव सीम्स तो दिस्कौरागे थे प्रोपगेशन ऑफ़ थे नोतिओं ठाट "wi-फि" स्तान्ड्स फ़ॉर "वायरलेस फिदेलिटी", बुत इत हस बीन रेफेर्रेड तो अस सुच ब्य थे wi-फि अलायंस इन व्हिते पपेर्स कर्रेंत्ल्य हेल्ड इन थेइर क्नोव्लेद्गे बसें: "... अ प्रोमिसिंग मार्केट फ़ॉर वायरलेस फिदेलिटी (wi-फि) नेत्वोर्क एक़ुइप्मेन्त्."
[13] and "A Short History of WLANs... The association created the Wi-Fi (Wireless Fidelity) logo to indicate that a product had been certified for interoperability."