History.

Early women's football.

Women may have been playing football for as long as the game has existed. Evidence shows that a similar game (cuju) was played by women during the Han Dynasty (25–220 CE). Two female figures are depicted in Han Dynasty frescoes, playing Tsu Chu. There are, however, a number of opinions about the accuracy of dates, the earliest estimates at 5000 BCE. Reports of an annual match being played in Scotland are reported as early as the 1790s. The first match recorded by the Scottish Football Association took place in 1892 in Glasgow. In England, the first recorded game of football between women took place in 1895.  The modern game of football (soccer) has documented early involvement of women. In Europe, it is possible that 12th-century French women played football as part of that era's folk games. An annual competition in Mid-Lothian, Scotland during the 1790s is reported, too. In 1863, football governing bodies introduced standardized rules to prohibit violence on the pitch, making it more socially acceptable for women to play.  The most well-documented early European team was founded by activist Nettie Honeyball in England in 1894. It was named the British Ladies' Football Club. Honeyball and those like her paved the way for women's football. However the women's game was frowned upon by the British football associations, and continued without their support. It has been suggested that this was motivated by a perceived threat to the'masculinity' of the game.  Women's football became popular on a large scale at the time of the First World War, when employment in heavy industry spurred the growth of the game, much as it had done for men fifty years earlier. A team from England played a team from Ireland on Boxing Day 1917 in front of a crowd of 20,000 spectators. The most successful team of the era was Dick, Kerr's Ladies of Preston, England. The team played in the first women's international matches in 1920, against a team from Paris, France, in April, and also made up most of the England team against a Scottish Ladies XI in 1920, winning 22–0.

FA Ban (1921–1971).

Despite being more popular than some men's football events (one match saw a 53,000 strong crowd), women's football in England was halted in 1921 when The Football Association outlawed the playing of the game on Association members' pitches, on the grounds stating that "the game of football is quite unsuitable for females and ought not to be encouraged." Some speculated that this may have also been due to envy of the large crowds that women's matches attracted. Despite the ban, some women's teams continued to play. The English Ladies Football Association was formed and play moved to rugby grounds.  The ban was maintained by the FA for fifty years until 1971. The same year, UEFA recommended that the national associations in each country should manage the women's game. It was not until 2008 (87 years later), that the FA issued an apology for banning women from the game of football. Six years prior in 2002, Lily Parr of Dick Kerr's Ladies FC, was the first woman to be inducted into the National Football Museum Hall of Fame. She was later honoured with a statue in front of the museum.  In August 1917, a tournament was launched for female munition workers' teams in northeast England. Officially titled the Tyne Wear & Tees Alfred Wood Munition Girls Cup, it was popularly known as The Munitionettes' Cup. The first winners of the trophy were Blyth Spartans, who defeated Bolckow Vaughan 5–0 in a replayed final tie at Middlesbrough on 18 May 1918 in front of a crowd of 22,000. The tournament ran for a second year in season 1918–19, the winners being the ladies of Palmer's shipyard in Jarrow, who defeated Christopher Brown's of Hartlepool 1–0 at St James' Park in Newcastle on 22 March 1919.  Following the FA ban on women's teams on 5 December 1921, the English Ladies' Football Association was formed. A silver cup was donated by the first president of the association, Len Bridgett. A total of 24 teams entered the first competition in the spring of 1922. The winners were Stoke Ladies who beat Doncaster and Bentley Ladies 3–1 on 24 June 1922.  In 1937 and 1938, the "Dick, Kerr's Ladies F.C." played Edinburgh City Girls in the "Championship of Great Britain and the World". Dick Kerr won the 1937 and 38 competitions with 5–1 score lines. The 1939 competition however was a more organised affair and the Edinburgh City Girls beat Dick Kerr in Edinburgh 5–2. The City Girls followed this up with a 7–1 demolition of Glasgow Ladies Ladies in Falkirk to take the title.

The'revival' of the women's game.

The English "Women's FA" was formed in 1969 (as a result of the increased interest generated by the 1966 World Cup), and the FA's ban on matches being played on members' grounds was finally lifted in 1971. In the same year, UEFA recommended that the women's game should be taken under the control of the national associations in each country.

Ladies World Championships, 1970 and 1971.

In 1970 an Italian ladies football federation, known as "Federazione Femminile Italiana Giuoco Calcio" or "FFIGC", ran a "World Championships" tournament in Rome supported by the Martini and Rossi strong wine manufacturers, entirely without the involvement of FIFA or any of the common National associations. This event was at least partly played by clubs. But a somewhat more successful World Championships with national teams was hosted by Mexico the following year. The final (won by Denmark) was played at the famous Estadio Azteca, the largest arena in the entire Americas north of the Panama Canal at the time, in front of no less than 112.500 attenders.  On 17 April 1971, in the French town of Hazebrouck, the first official women's international football match was played between France and the Netherlands.

Professionalism.

During the 1970s, Italy became the first country to introduce professional women's football players, on a part-time basis. Italy was also the first country to import foreign footballers from other Europeans countries, which raised the profile of the league. The most prominent players during that era included Susanne Augustesen (Denmark), Rose Reilly and Edna Neillis (Scotland), Anne O'Brien (Ireland) and Concepcion Sánchez Freire (Spain).

Asia and Oceania.

In 1989, Japan became the first country to have a semi-professional women's football league, the L. League – still in existence today as Division 1 of the Nadeshiko League.  In Australia, the W-League was formed in 2008.  In 2015, the Chinese Women's Super League (CWSL) was launched with an affiliated second division, CWFL. Previously, The Chinese Women's Premier Football League was initiated in 1997 and evolved to the Women's Super League in 2004. From 2011 to 2014, the league named Women's National Football League.  The Indian Women's League was launched in 2016. The country has held the top-tier tournament, Indian Women's Football Championship, since 1991.

North America.

In 1985, the United States national soccer team was formed. Following the success of the 1999 FIFA Women's World Cup, the first professional women's soccer league in the United States, the WUSA, was launched, and lasted three years. The league was spearheaded by members of the World Cup-winning American team and featured players like Mia Hamm, Julie Foudy, Brandi Chastain as well as top-tier international players like Germany's Birgit Prinz and China's Sun Wen. A second attempt towards a sustainable professional league, the Women's Professional Soccer (WPS), was launched in 2009 and folded in late 2011. The following year, the National Women's Soccer League (NWSL) was launched with initial support from the United States, Canadian, and Mexico federations., it is in its eighth year.  In 2017, Liga MX Femenil was launched in Mexico and broke several attendance records. The league is composed of women's teams for the men's counterpart teams in Liga MX.

21st century.

At the beginning of the 21st century, women's football, like men's football, is growing in both popularity and participation as well as more professional leagues worldwide. From the inaugural FIFA Women's World Cup tournament held in 1991 to the 1,194,221 tickets sold for the 1999 Women's World Cup visibility and support of women's professional football has increased around the globe.  However, as in numerous other sports, women's pay and opportunities are much lower in comparison with professional male football players. Major league and international women's football have far less television and media coverage than the men's equivalent. Games can be regarded as being an ordeal to be "endured rather than enjoyed... more out of duty than expectation". The popularity and participation in women's football continues to grow. While several features continue to improve, this is not the case for female coaches. They continue to be underrepresented in several European women's leagues.

International competitions.

The growth in women's football has seen major competitions being launched at both the national and international levels.

Women's World Cup.

Prior to the 1991 establishment of the FIFA Women's World Cup, several unofficial world tournaments took place in the 1970s and 1980s, including the FIFA's Women's Invitation Tournament 1988, which was hosted in China.  The first Women's World Cup was held in the People's Republic of China, in November 1991, and was won by the United States (USWNT). The third Cup, held in the United States in June and July 1999, drew worldwide television interest and a final in front of a record-setting 90,000+ Pasadena crowd, where the United States won 5–4 on penalty kicks against China. The US are the reigning champions, having won in Canada in 2015, and in France, in 2019.

Olympics.

Since 1996, a Women's Football Tournament has been staged at the Olympic Games. Unlike in the men's Olympic Football tournament (based on teams of mostly under-23 players), the Olympic women's teams do not have restrictions due to professionalism or age.  England and other British Home Nations are not eligible to compete as separate entities because the International Olympic Committee does not recognise their FIFA status as separate teams in competitions. The participation of UK men's and women's sides at the 2012 Olympic tournament was a bone of contention between the four national associations in the UK from 2005, when the Games were awarded to London, to 2009. England was strongly in favour of unified UK teams, while Scotland, Wales, and Northern Ireland were opposed, fearing adverse consequences for the independent status of the Home Nations within FIFA. At one stage it was reported that England alone would field teams under the UK banner (officially "Great Britain") for the 2012 Games. However, both the men's and women's Great Britain teams eventually fielded some players from the other home nations. (See Football at the 2012 Summer Olympics – Women's tournament)

UEFA Women's Championship.

What is now known worldwide as the UEFA Women's Championship (or Women's Euro) was initially launched in 1982 under the name European Competition For Representative Women's Teams and recognized by UEFA as an official tournament. Previously, European women's tournaments featuring national teams were held in Italy in 1969 and 1979, but were not recognized as "official" due to the FA Ban.  The 1984 Finals was won by Sweden. Norway won, in the 1987 Finals. Since then, the UEFA Women's Championship has been dominated by Germany, which has won eight out of the 10 events to date. The only other teams to win are Norway, which won in 1993, and the reigning champions, the Netherlands, which won at home in 2017.

Copa Libertadores Femenina.

Copa Libertadores Femenina (Women's Liberators Cup), formally known as CONMEBOL Libertadores Femenina, is the international women's football club competition for teams that play in CONMEBOL nations. The competition started in the 2009 season in response to the increased interest in women's football. It is the only CONMEBOL club competition for women.

Domestic competitions.

England.

Football Association Women's Challenge Cup (FA Women's Cup).

After the lifting of the F.A. ban, the now defunct Women's Football Association held its first national knockout cup in 1970–71. It was called the Mitre Trophy which became the FA Women's Cup in 1993. Southampton WFC was the inaugural winner. From 1983 to 1994 Doncaster Belles reached ten out of 11 finals, winning six of them. Chelsea are the current holders and Arsenal are the most successful club with a record 14 wins. Despite tournament sponsorship by major companies, entering the cup actually costs clubs more than they get in prize money. In 2015 it was reported that even if Notts County had won the tournament outright the paltry £8,600 winnings would leave them out of pocket. The winners of the men's FA Cup in the same year received £1.8 million, with teams not even reaching the first round proper getting more than the women's winners.

Youth tournaments.

In 2002, FIFA inaugurated a women's youth championship, officially called the FIFA U-19 Women's World Championship. The first event was hosted by Canada. The final was an all-CONCACAF affair, with the USA defeating the host Canadians 1–0 with an extra-time golden goal. The second event was held in Thailand in 2004 and won by Germany. The age limit was raised to 20, starting with the 2006 event held in Russia. Demonstrating the increasing global reach of the women's game, the winners of this event were North Korea. The tournament was renamed the FIFA U-20 Women's World Cup, effective with the 2008 edition won by the US in Chile. The current champions are Japan, who won in France in 2018.  In 2008, FIFA instituted an under-17 world championship. The inaugural event, held in New Zealand, was won by North Korea. The current champions at this level are Spain, who won in Uruguay in 2018.

Intercollegiate.

United States.

In the United States, the intercollegiate sport began from physical education programs that helped establish organized teams. After sixty years of trying to gain social acceptance women's football was introduced to the college level. In the late 1970s, women's club teams started to appear on college campus, but it wasn't until the 1980s that they started to gain recognition and gained a varsity status. Brown University was the first college to grant full varsity level status to their women's soccer team. The Association of Intercollegiate Athletics for Women (AIAW) sponsored the first regional women's soccer tournament at college in the US, which was held at Brown University. The first national level tournament was held at Colorado College, which gained official AIAW sponsorship in 1981. The 1990s saw greater participation mainly due to the Title IX of 23 June 1972, which increased school's budgets and their addition of women's scholarships. "Currently there are over 700 intercollegiate women's soccer teams playing for many types and sizes of colleges and universities. This includes colleges and universities that are members of the National Collegiate Athletic Association (NCAA), National Association of Intercollegiate Athletics (NAIA), and the National Junior College Athletic Association (NJCAA)."

Attire.

The majority of women footballers around the globe wear a traditional kit made up of a jersey, shorts, cleats and knee-length socks worn over shin guards.

Controversies.

In 2004, FIFA President Sepp Blatter suggested that women footballers should "wear tighter shorts and low cut shirts... to create a more female aesthetic" and attract more male fans. His comment was criticized as sexist by numerous people involved with women's football and several media outlets worldwide. In September 2008, FC de Rakt women's team (FC de Rakt DA1) in the Netherlands made international headlines by swapping its old kit for a new one featuring short skirts and tight-fitting shirts. This innovation, which had been requested by the team itself, was initially vetoed by the Royal Dutch Football Association on the grounds that according to the rules of the game shorts must be worn by all players, both male and female; but this decision was reversed when it was revealed that the FC de Rakt team were wearing hot pants under their skirts, and were therefore technically in compliance. Denying that the kit change was merely a publicity stunt, club chairman Jan van den Elzen told Reuters:  21-year-old team captain Rinske Temming said:  In June 2011, Iran forfeited an Olympic qualification match in Jordan, after trying to take to the field in hijabs and full body suits. FIFA awarded a default 3–0 win to Jordan, explaining that the Iranian kits were "an infringement of the Laws of the Game", due to safety concerns. The decision provoked strong criticism from Mahmoud Ahmadinejad while Iranian officials alleged that the actions of the Bahraini match delegate had been politically motivated. In July 2012, FIFA approved the wearing of hijab in future matches.  Also in June 2011, Russian UEFA Women's Champions League contenders WFC Rossiyanka announced a plan to play in bikinis in a bid to boost attendances.

See also.

TV football

Women's association football, usually known as women's football or women's soccer, is the team sport of association football when played by women's teams only. It is played at the professional level in numerous countries throughout the world and 176 national teams participate internationally.

Le football féminin, ou soccer féminin, raccourci utilisé pour désigner le football lorsqu'il est pratiqué par les femmes, suit exactement les mêmes règles que le football pratiqué par les hommes. Il connaît son âge d'or au début des années 1920, jusqu'au bannissement des femmes des terrains par l'association britannique de football, interdiction qui dure de 1921 à 1971, puis en France par l'interdiction faite aux femmes de pratiquer. Aujourd'hui, il connaît un essor considérable de ses pratiquantes, grâce notamment au soutien de la FIFA et des associations membres, mais fait l'objet d'un intérêt très mitigé par les médias.


Early life and pre-war career.

Born in Kharkiv, in the Kharkov Governorate of the Russian Empire (present-day Ukraine), she was the daughter of Stepan Vasilyevich Grizodubov, a pioneer aircraft-designer. At the age of fourteen, she flew a glider solo. She played piano and graduated from a conservatory as well as from the Kharkov Technical Institute. She spoke several foreign languages. In 1929, she graduated from the Penza Flying Club of the paramilitary association "OSOAVIAKhIM". She also trained at the Kharkov Flight School.  In 1933, she graduated from the Tula Advanced Flying School. Here she became a flight instructor and trained 86 male pilots, many of whom became Heroes of Soviet Union. From 1934 to 1938, she flew in a ""Propaganda"" Squadron named after Maxim Gorky.  She flew many types of aircraft and set seven world records including one for highest altitude reached by a female pilot on a two-seater seaplane, 3,267 meters (10718.5 feet) on 15 October 1937, (FAI Record File Number 121.16) three speed records and one for long-distance flying between Moscow and Aktyubinsk together with Marina Raskova.  On September 24–25, 1938, flying as pilot-in-command with Marina Raskova as navigator and Polina Osipenko as co-pilot, she completed the 5,910 kilometer-long flight named "Rodina" (Russian for "Motherland") on an Antonov ANT-37, setting an international women's record for a straight-line distance flight (FAI Record File Number 10444). She had already accumulated 5000 flight hours flight before the historic event; after the flight she and her crew members became the first women awarded the title Hero of the Soviet Union on 2 November 1938, also receiving a reward of 25,000 rubles.

German-Soviet War.

Since March 1942 she took part in the German-Soviet War. She was appointed commanding officer of the 101st Long-Range Air Regiment, formed in May 1942, which consisted of about three-hundred men: pilots, navigators, engineers and ground support personnel. Her unit was equipped with Lisunov Li-2, transport aircraft (Douglas DC-3 built under license) with pilots conscripted from the Civil Air Fleet.  Grizodubova's Li-2s had a crew of six aviators: pilot, co-pilot, navigator, flight-technician, radio operator and air gunner. The unit had initially the task of bombing enemy troops, to fly to partisans and - in June 1942 - to help supply the besieged Leningrad. Subsequently, 101st Long-Range Bomber Air Regiment was ordered to bomb Wehrmacht units that had broken Bryansk and South-Westerns Fronts and were heading for Voronezh. Grizodubova led her regiment almost every night, overcoming strong flak defences and Luftwaffe night fighters in Kursk, Orel and L'gov areas.  In September 1942, 101st Long-Range Air Regiment was placed at disposal of the Central HQ of the Partisan Movement. The unit flew more than 1,850 sorties to partisan-held areas, delivering about 1,500 tons of arms and ammunition and hundreds of tons of radio equipment, printing presses, film cameras and reading matter, for Soviet partisan leaders. The Regiment evacuated 2,500 wounded partisans and homeless orphans too. However, poor airstrips and enemy fighters were a constant threat to the Li-2s and their crews. On Grizodubova's initiative, by March 1943, partisans built an improved airstrip on the right bank of the Dnieper, where up to a dozen aircraft could be parked in daytime. On 27 May 1944 her regiment was awarded the honorific title "Krasnosel'skiy" for participating to break the siege of Leningrad. By the time Grizodubova was recalled to Moscow, in June 1944, she had flown about 200 sorties. Two months later, on 30 August, the 101st Long-Range Aviation Regiment was awarded the Order of the Red Banner and, later, the honorific of "Guards".

Post war.

In the 1940s she served as the sole female member of the ""Extraordinary State Commission for Ascertaining and Investigating Crimes Perpetrated by the German-Fascist Invaders and their Accomplices"" (Chrezvychainaia gosudarstvennaia komissiia or Чрезвычайная Государственная Комиссия; ChGK), appointed to investigate Nazi war crimes in the Soviet Union and compensate the state for damages. She also assisted the future cosmonaut Svetlana Savitskaya in becoming a test pilot.

Legacy.

Grizodubova was an Honorary Citizen of Penza. A monument in Moscow is dedicated to Valentina Grizodubova.

Valentina Stepanovna Grizodubova (, "Valentyna Stepanivna Hryzodubova"; in Kharkov – 28 April 1993 in Moscow) was one of the first female pilots in the Soviet Union awarded the title Hero of the Soviet Union and the only female Hero of the Soviet Union to also be awarded the title Hero of Socialist Labour.

Valentina Stepanovna Grizodoubova ( ; ) est une aviatrice soviétique, née le à Kharkiv (Empire russe) et décédée le à Moscou (Russie). Après avoir battu plusieurs records de distance de vol sans escale, elle fut pilote dans les Forces aériennes soviétiques pendant la Seconde Guerre mondiale et fut la première femme distinguée par le titre de Héros de l'Union soviétique.


Technology.

Many organizations have developed autostereoscopic 3D displays, ranging from experimental displays in university departments to commercial products, and using a range of different technologies. The method of creating autostereoscopic flat panel video displays using lenses was mainly developed in 1985 by Reinhard Boerner at the Heinrich Hertz Institute (HHI) in Berlin. Prototypes of single-viewer displays were already being presented in the 1990s, by Sega AM3 (Floating Image System) and the HHI. Nowadays, this technology has been developed further mainly by European and Japanese companies. One of the best-known 3D displays developed by HHI was the Free2C, a display with very high resolution and very good comfort achieved by an eye tracking system and a seamless mechanical adjustment of the lenses. Eye tracking has been used in a variety of systems in order to limit the number of displayed views to just two, or to enlarge the stereoscopic sweet spot. However, as this limits the display to a single viewer, it is not favored for consumer products.  Currently, most flat-panel displays employ lenticular lenses or parallax barriers that redirect imagery to several viewing regions; however, this manipulation requires reduced image resolutions. When the viewer's head is in a certain position, a different image is seen with each eye, giving a convincing illusion of 3D. Such displays can have multiple viewing zones, thereby allowing multiple users to view the image at the same time, though they may also exhibit dead zones where only a non-stereoscopic or pseudoscopic image can be seen, if at all.

Parallax barrier.

A parallax barrier is a device placed in front of an image source, such as a liquid crystal display, to allow it to show a stereoscopic image or multiscopic image without the need for the viewer to wear 3D glasses. The principle of the parallax barrier was independently invented by Auguste Berthier, who published first but produced no practical results, and by Frederic E. Ives, who made and exhibited the first known functional autostereoscopic image in 1901. About two years later, Ives began selling specimen images as novelties, the first known commercial use.  In the early 2000s, Sharp developed the electronic flat-panel application of this old technology to commercialization, briefly selling two laptops with the world's only 3D LCD screens. These displays are no longer available from Sharp but are still being manufactured and further developed from other companies. Similarly, Hitachi has released the first 3D mobile phone for the Japanese market under distribution by KDDI. In 2009, Fujifilm released the FinePix Real 3D W1 digital camera, which features a built-in autostereoscopic LCD measuring diagonal. The Nintendo 3DS video game console family uses a parallax barrier for 3D imagery; on a newer revision, the New Nintendo 3DS, this is combined with an eye tracking system.

Integral photography and lenticular arrays.

The principle of integral photography, which uses a two-dimensional (X-Y) array of many small lenses to capture a 3-D scene, was introduced by Gabriel Lippmann in 1908. Integral photography is capable of creating window-like autostereoscopic displays that reproduce objects and scenes life-size, with full parallax and perspective shift and even the depth cue of accommodation, but the full realization of this potential requires a very large number of very small high-quality optical systems and very high bandwidth. Only relatively crude photographic and video implementations have yet been produced.  One-dimensional arrays of cylindrical lenses were patented by Walter Hess in 1912. By replacing the line and space pairs in a simple parallax barrier with tiny cylindrical lenses, Hess avoided the light loss that dimmed images viewed by transmitted light and that made prints on paper unacceptably dark. An additional benefit is that the position of the observer is less restricted, as the substitution of lenses is geometrically equivalent to narrowing the spaces in a line-and-space barrier.  Philips solved a significant problem with electronic displays in the mid-1990s by slanting the cylindrical lenses with respect to the underlying pixel grid. Based on this idea, Philips produced its WOWvx line until 2009, running up to 2160p (a resolution of 3840×2160 pixels) with 46 viewing angles. Lenny Lipton's company, StereoGraphics, produced displays based on the same idea, citing a much earlier patent for the slanted lenticulars. Magnetic3d and Zero Creative have also been involved.

Compressive light field displays.

With rapid advances in optical fabrication, digital processing power, and computational models for human perception, a new generation of display technology is emerging: compressive light field displays. These architectures explore the co-design of optical elements and compressive computation while taking particular characteristics of the human visual system into account. Compressive display designs include dual and multilayer devices that are driven by algorithms such as computed tomography and Non-negative matrix factorization and non-negative tensor factorization.

Autostereoscopic content creation and conversion.

Tools for the instant conversion of existing 3D movies to autostereoscopic were demonstrated by Dolby, Stereolabs and Viva3D.

Other.

Dimension Technologies released a range of commercially available 2D/3D switchable LCDs in 2002 using a combination of parallax barriers and lenticular lenses. SeeReal Technologies has developed a holographic display based on eye tracking. CubicVue exhibited a color filter pattern autostereoscopic display at the Consumer Electronics Association's i-Stage competition in 2009.  There are a variety of other autostereo systems as well, such as volumetric display, in which the reconstructed light field occupies a true volume of space, and integral imaging, which uses a fly's-eye lens array.  The term "automultiscopic display" has recently been introduced as a shorter synonym for the lengthy "multi-view autostereoscopic 3D display", as well as for the earlier, more specific "parallax panoramagram". The latter term originally indicated a continuous sampling along a horizontal line of viewpoints, e.g., image capture using a very large lens or a moving camera and a shifting barrier screen, but it later came to include synthesis from a relatively large number of discrete views.  Sunny Ocean Studios, located in Singapore, has been credited with developing an automultiscopic screen that can display autostereo 3D images from 64 different reference points.  A fundamentally new approach to autostereoscopy called HR3D has been developed by researchers from MIT's Media Lab. It would consume half as much power, doubling the battery life if used with devices like the Nintendo 3DS, without compromising screen brightness or resolution; other advantages include a larger viewing angle and maintaining the 3D effect when the screen is rotated.

Movement parallax: single view vs. multi-view systems.

Movement parallax refers to the fact that the view of a scene changes with movement of the head. Thus, different images of the scene are seen as the head is moved from left to right, and from up to down.  Many autostereoscopic displays are single-view displays and are thus not capable of reproducing the sense of movement parallax, except for a single viewer in systems capable of eye tracking.  Some autostereoscopic displays, however, are multi-view displays, and are thus capable of providing the perception of left-right movement parallax. Eight and sixteen views are typical for such displays. While it is theoretically possible to simulate the perception of up-down movement parallax, no current display systems are known to do so, and the up-down effect is widely seen as less important than left-right movement parallax. One consequence of not including parallax about both axes becomes more evident as objects increasingly distant from the plane of the display are presented: as the viewer moves closer to or farther away from the display, such objects will more obviously exhibit the effects of perspective shift about one axis but not the other, appearing variously stretched or squashed to a viewer not positioned at the optimum distance from the display.

Autostereoscopy is any method of displaying stereoscopic images (adding binocular perception of 3D depth) without the use of special headgear or glasses on the part of the viewer. Because headgear is not required, it is also called "glasses-free 3D" or "glassesless 3D". There are two broad approaches currently used to accommodate motion parallax and wider viewing angles: eye-tracking, and multiple views so that the display does not need to sense where the viewers' eyes are located. Examples of autostereoscopic displays technology include lenticular lens, parallax barrier, volumetric display, holographic and light field displays.

L'auto-stéréoscopie est un type de représentation d'image en relief ou stéréoscopique ne nécessitant aucun dispositif complémentaire pour restituer l'effet tridimensionnel. Ainsi, un écran auto-stéréoscopique affiche l'effet de relief sans que, par exemple, le port de lunettes spéciales associées soit nécessaire. Pour le grand public, on parle en général de 3D sans lunette.


Functions.

Celestia displays the Hipparcos Catalogue (HIP) of 118,322 stars and a compiled catalogue of galaxies. Celestia uses the VSOP87 theory of planetary orbits to provide a solar and lunar eclipse finder and to display the orbital paths of planets (including extrasolar planets), dwarf planets, moons, asteroids, comets, artificial satellites, and spacecraft.  Using the installed catalogues, the names of celestial objects can be displayed, including artificial satellites, as well as the names and locations of Earth features.  Celestia allows users to navigate at different speeds, and allow users to orbit stars, planets, moons, and other space objects, track space objects such as spacecraft, asteroids, and comets as they fly by, or travel to and/or fly through galaxies. Light time delay is an optional function.  The time simulated by Celestia can be set to any time 2 billion years forward or backward from the present, although planetary orbits are only accurate within a few thousand years of the present day, and  Celestia simulates the appearance of atmospheres on planets and moons, planetshine on orbiting satellites, and miscellaneous planetary details such as sunrise and sunset. Information about the objects that Celestia draws can also be displayed.  The user can change Celestia's field of view, and allows users to split the window into multiple panes. Screenshots and movies can be captured in classic or HD resolutions. Celestia's support for gamepads and joysticks is relatively limited.  Celestia can be extended with new objects, and has support for third-party, user-created add-ons available for installation, both fictional and realistic. The extension mechanism uses Lua as its built-in scripting language.

Limitations.

The default setting for Celestia's Earth is a spheroid. The irregular surface of the Earth causes low Earth orbit satellites to appear to be in the wrong places in the sky when watched from Celestia's ground, even when the Earth's oblateness is specified.  Many types of astronomical objects are not included with Celestia. Variable stars, supernovae, black holes, and nebulae are missing from the standard distribution. Some are available as add-ons.  Although objects that form part of a planetary system move, and stars rotate about their axes and orbit each other in multiple star systems, stellar proper motion is not simulated, and galaxies are at fixed locations. As a result, the constellations in Celestia do not gradually change shape as they do in the real world. In addition, Celestia's binary star catalogs only describe a few hundred systems of multiple stars. Most binary star systems cannot be simulated because adequate orbital information is not yet available.  Celestia does not include any stars that are more than a few thousand light-years from the Sun because the parallaxes of more distant stars are too small to be accurately measured by the Hipparcos astrometric satellite. In addition, objects in solar systems are only drawn to a distance of one light-year from their suns, and Celestia does not consider the wobbling of some stars induced by their planets.  Wavelength filtering is not implemented in Celestia's engine. The actual rendering tries to match human vision at the observer's position as accurately as possible. This means false-color maps and multi-color nebulae are not part of the official distribution. Camera artifacts such as lens flare and glare are not rendered.  Celestia also does not simulate gravity. For example, a near-Earth object approaching the Earth will not be deflected by the Earth's gravity unless the person who defined the NEO's trajectory for Celestia included that effect.  Some moons do not cast shadows on their planet during eclipses. This is because irregularly shaped objects do not cast shadows in the current version of Celestia, although this is planned for future versions.  Most real-world spacecraft such as "Voyager 2" are not available in Celestia but are provided as add-ons by users.  Celestia uses the Julian calendar and cannot go back or forward more than 2 billion years, and the default time-setting system cannot go further than the years -9999 or 9999.

Add-ons.

Well over 10 GB of extensions are available in addition to the base program, produced by an active user community.  Higher resolution surface textures are available for most solar system bodies, including Virtual Textures with coverage up to 32768 pixels wide (1.25 km/pixel at the Earth's equator), with selected coverage at higher resolutions. This allows closer views of the Earth, Mars, and the Moon. 3D models of historical and existing spacecraft are available flying in reasonably accurate trajectories, such as Sputnik 1, Voyager 2, the Hubble Space Telescope, and the International Space Station, as are extended data plots for stars (2 million with correct spatial coordinates), DSOs (nebulae, galaxies, open clusters, etc.), as well as catalogs of asteroids and comets, and more than 96,000 locations on the Earth can be drawn by the program. Add-ons also include space objects such as red and blue supergiants, red and brown dwarfs, neutron stars, spinning pulsars, rotating black holes with accretion disks, protostars, star nursery nebulae, supernova remnants, planetary nebulae, galactic redshifts, geological planetary displays (e.g. 3D interiors, topographic and bathymetric maps, paleogeography), planetary aurorae, rotating magnetic fields, animated solar prominences, 3D craters and mountains, and historic collision events.  Numerous scripts are available. These include simple tours, reconstructions of complex space missions such as Cassini–Huygens and "Deep Impact", and scripts showing useful information, like size comparisons, or particular events such as multiple simultaneous eclipses of Jupiter's moons or the evolution of a star.  Fictional universes can be depicted, with planetary systems and 3D models—films such as "", "Star Trek" and "Star Wars", and TV shows including "Stargate SG-1" and "Babylon 5". Add-ons illustrating less well-known Web fiction, like "Orion's Arm", or role-playing games, like 2300 AD, and personal works by members of the Celestia community depicting fictional solar systems with inhabited worlds, spacecraft, cities, and special effects can also be added.  Educational add-ons can also be implemented in different languages. These activities provide approximately 40 hours of space journeys and astronomical lessons to include extensive tours of the Celestia universe, the complete life cycle of stars, the solar system, the human space program, the Search for Extraterrestrial Intelligence (SETI), and depictions of astronomical events such as the formation of our moon billions of years ago, and the possible terraforming of Mars in the future.  In late 2017, a massive addon pack project called Celestia Origin was created, which replaces all vanilla textures and graphics with higher-quality renderings.

Uses in media.

NASA and ESA have used Celestia in their educational and outreach programs, as well as for interfacing to trajectory analysis software.  Celestia was used in the media by the CBS television show "NCIS" (Season 4, Episode 22: "In the Dark"). Character Timothy McGee explains what Celestia is and how an add-on can allow the user to store a diary within the program, as well. Textures designed by Celestia graphic artists were used in the movie "The Day After Tomorrow" and the 2008 miniseries "The Andromeda Strain". Celestia has also appeared on the Science Channel's "Through the Wormhole". Eurogamer's Jim Rossignol named "Celestia" among a top 20 list of "Summer of PC" Freeware games in 2006.

Celestia is a 3D astronomy software program created by Chris Laurel. The program allows users to virtually travel through a computer generated universe. Celestia can display objects of various scales using OpenGL.

Celestia est un simulateur spatial libre permettant d'observer le Système solaire et le reste de l'univers en temps réel, en 3D avec un réalisme de qualité photographique. Il est utilisé à des fins éducatives dans de nombreuses écoles et planétariums du monde. Celestia est distribué gratuitement et s'exécute sur de nombreux systèmes d'exploitation, dont Windows, Mac OS X, GNU/Linux.


Race.

Phil Hill, running second in the championship, was in the stands with a camera around his neck; a metal workers' strike in Italy meant that Ferrari could not take part. This left Graham Hill the fastest on track, taking the lead at the start and also setting a new lap record. The leading pack also included John Surtees (Lola), Jim Clark (Lotus), and Bruce McLaren (Cooper). These four pulled steadily away from Jack Brabham (Lotus) and Dan Gurney (Porsche). After only nine laps Brabham was out of the race with a broken rear suspension, while McLaren lost fourth gear and spun off the track, rejoining the race far down the field. Surtees had to stop four laps later with ignition problems, but was back on track in eighth place. Hill had pulled out a twenty-second lead ahead of Clark, but on the thirtieth lap he made contact with Jackie Lewis' Cooper when lapping him, allowing Clark to pass. Hill gave chase, netting the lap record, and re-took the lead on lap 33. On the next lap, Clark had to stop with a broken front suspension. Hill and BRM looked sure to win, but on lap 42 he stopped in a hairpin with fuel injection and throttle linkage troubles; he lost several laps and ended up dead last after also having stopped in the hairpin to pick up the engine cover that he had left behind during his earlier visit there.  All of a sudden Gurney found himself in the lead, he made no mistakes and gained what was to be Porsche's only Grand Prix victory with their own car. Tony Maggs had second place handed to him in what was only his second race in a V8 Cooper, while Surtees' Lola kept giving him trouble. With only fourth gear left, he was passed by Richie Ginther on the 43rd lap. Ginther's car had refused to start, setting him a half lap back at the start, but as cars ahead of him all began to break he drove harder and harder. His troubles were not over, however, with five laps left his throttle wire snapped and he had to control it with his hand - rather troublesome since his BRM's gear shifter was also on the right hand side. McLaren was forced to make another pit stop, but managed to get by the troubled Surtees on the very last lap. The last points scoring position went to the ever steady Carel Godin de Beaufort in his uncompetitive Porsche 718 from 1961.  Other contenders were Jo Bonnier, who had gearbox and engine troubles. Later he stopped with fuel starvation, but got the car started and was classified as the last finisher, in tenth. Maurice Trintignant had to make a number of pit stops in his Rob Walker Lotus 24. Trevor Taylor had not been able to practice and was taking it comparatively easy when his throttle return spring broke, leaving it fully open. After a pit stop, he finished eighth, six laps down. A rather confusing race ended even worse - Surtees was trying to eke his crippled car into the pits but was hindered by a wall of gendarmes, who were refusing to move. Trintignant moved over to the left, but Taylor arrived at a high speed and rear ended Trintignant. Both cars ended up in the haybales, badly damaged, but amazingly no one was injured.  At the end, Phil Hill took his countryman Gurney aside and thanked him for "driving so well for him", as both of his closest competitors ended the race without any points.

The 1962 French Grand Prix was a Formula One motor race held at Rouen-Les-Essarts on 8 July 1962. It was race 4 of 9 in both the 1962 World Championship of Drivers and the 1962 International Cup for Formula One Manufacturers. The race was won by Dan Gurney, his first Formula One victory, driving a Porsche, that company's only win as a constructor in a Formula One championship race coming after three years of racing. It was the third time that the French Grand Prix was held at Rouen, last time being 1957.

Le Grand Prix de France 1962 (XLVIII Grand Prix de l'A.C.F.), disputé sur le circuit de Rouen-les-Essarts le, est la cent-sixième épreuve du championnat du monde de Formule 1 courue depuis 1950 et la quatrième manche du championnat 1962.


Role and functioning.

MPLS is scalable and protocol-independent. In an MPLS network, data packets are assigned labels. Packet-forwarding decisions are made solely on the contents of this label, without the need to examine the packet itself. This allows one to create end-to-end circuits across any type of transport medium, using any protocol. The primary benefit is to eliminate dependence on a particular OSI model data link layer (layer 2) technology, such as Asynchronous Transfer Mode (ATM), Frame Relay, Synchronous Optical Networking (SONET) or Ethernet, and eliminate the need for multiple layer-2 networks to satisfy different types of traffic. Multiprotocol label switching belongs to the family of packet-switched networks.  MPLS operates at a layer that is generally considered to lie between traditional definitions of OSI Layer 2 (data link layer) and Layer 3 (network layer), and thus is often referred to as a "layer 2.5" protocol. It was designed to provide a unified data-carrying service for both circuit-based clients and packet-switching clients which provide a datagram service model. It can be used to carry many different kinds of traffic, including IP packets, as well as native ATM, SONET, and Ethernet frames.  A number of different technologies were previously deployed with essentially identical goals, such as Frame Relay and ATM. Frame Relay and ATM use "labels" to move frames or cells throughout a network. The header of the Frame Relay frame and the ATM cell refers to the virtual circuit that the frame or cell resides on. The similarity between Frame Relay, ATM, and MPLS is that at each hop throughout the network, the “label” value in the header is changed. This is different from the forwarding of IP packets. MPLS technologies have evolved with the strengths and weaknesses of ATM in mind. MPLS is designed to have lower overhead than ATM while providing connection-oriented services for variable-length frames, and has replaced much use of ATM in the market.  In particular, MPLS dispenses with the cell-switching and signaling-protocol baggage of ATM. MPLS recognizes that small ATM cells are not needed in the core of modern networks, since modern optical networks are so fast (, at 200 Gbit/s and beyond) that even full-length 1500 byte packets do not incur significant real-time queuing delays (the need to reduce such delays — "e.g.", to support voice traffic — was the motivation for the cell nature of ATM).  At the same time, MPLS attempts to preserve the traffic engineering (TE) and out-of-band control that made Frame Relay and ATM attractive for deploying large-scale networks.

History.

In 1996 a group from Ipsilon Networks proposed a "flow management protocol". Their "IP Switching" technology, which was defined only to work over ATM, did not achieve market dominance. Cisco Systems introduced a related proposal, not restricted to ATM transmission, called "Tag Switching" (with its Tag Distribution Protocol TDP). It was a Cisco proprietary proposal, and was renamed "Label Switching". It was handed over to the Internet Engineering Task Force (IETF) for open standardization. The IETF work involved proposals from other vendors, and development of a consensus protocol that combined features from several vendors' work.  One original motivation was to allow the creation of simple high-speed switches since for a significant length of time it was impossible to forward IP packets entirely in hardware. However, advances in VLSI have made such devices possible. Therefore, the advantages of MPLS primarily revolve around the ability to support multiple service models and perform traffic management. MPLS also offers a robust recovery framework that goes beyond the simple protection rings of synchronous optical networking (SONET/SDH).

Operation.

MPLS works by prefixing packets with an MPLS header, containing one or more labels. This is called a label stack. Each entry in the label stack contains four fields:  These MPLS-labeled packets are switched after a label lookup/switch instead of a lookup into the IP table. As mentioned above, when MPLS was conceived, label lookup and label switching were faster than a routing table or RIB (Routing Information Base) lookup because they could take place directly within the switched fabric and avoid having to use the OS.  The presence of such a label, however, has to be indicated to the router/switch. In the case of Ethernet frames this is done through the use of EtherType values 0x8847 and 0x8848, for unicast and multicast connections respectively.

Label switch router.

An MPLS router that performs routing based only on the label is called a label switch router (LSR) or transit router. This is a type of router located in the middle of an MPLS network. It is responsible for switching the labels used to route packets.  When an LSR receives a packet, it uses the label included in the packet header as an index to determine the next hop on the label-switched path (LSP) and a corresponding label for the packet from a lookup table. The old label is then removed from the header and replaced with the new label before the packet is routed forward.

Label edge router.

A label edge router (LER, also known as edge LSR) is a router that operates at the edge of an MPLS network and acts as the entry and exit points for the network. LERs "push" an MPLS label onto an incoming packet and "pop" it off an outgoing packet. Alternatively, under penultimate hop popping this function may instead be performed by the LSR directly connected to the LER.  When forwarding an IP datagram into the MPLS domain, a LER uses routing information to determine the appropriate label to be affixed, labels the packet accordingly, and then forwards the labeled packet into the MPLS domain. Likewise, upon receiving a labeled packet which is destined to exit the MPLS domain, the LER strips off the label and forwards the resulting IP packet using normal IP forwarding rules.

Provider router.

In the specific context of an MPLS-based virtual private network (VPN), LERs that function as ingress and/or egress routers to the VPN are often called PE (Provider Edge) routers. Devices that function only as transit routers are similarly called P (Provider) routers. The job of a P router is significantly easier than that of a PE router, so they can be less complex and may be more dependable because of this.

Label Distribution Protocol.

Labels are distributed between LERs and LSRs using the Label Distribution Protocol (LDP). LSRs in an MPLS network regularly exchange label and reachability information with each other using standardized procedures in order to build a complete picture of the network so they can then use to forward packets.

Label-switched paths.

Label-switched paths (LSPs) are established by the network operator for a variety of purposes, such as to create network-based IP virtual private networks or to route traffic along specified paths through the network. In many respects, LSPs are not different from permanent virtual circuits (PVCs) in ATM or Frame Relay networks, except that they are not dependent on a particular layer-2 technology.

Routing.

When an unlabeled packet enters the ingress router and needs to be passed on to an MPLS tunnel, the router first determines the forwarding equivalence class (FEC) for the packet and then inserts one or more labels in the packet's newly created MPLS header. The packet is then passed on to the next hop router for this tunnel.  The MPLS Header is added between the network layer header and link layer header of the OSI model.  When a labeled packet is received by an MPLS router, the topmost label is examined. Based on the contents of the label a "swap", "push" ("impose") or "pop" ("dispose") operation is performed on the packet's label stack. Routers can have prebuilt lookup tables that tell them which kind of operation to do based on the topmost label of the incoming packet so they can process the packet very quickly.  During these operations, the contents of the packet below the MPLS Label stack are not examined. Indeed, transit routers typically need only to examine the topmost label on the stack. The forwarding of the packet is done based on the contents of the labels, which allows "protocol-independent packet forwarding" that does not need to look at a protocol-dependent routing table and avoids the expensive IP longest prefix match at each hop.  At the egress router, when the last label has been popped, only the payload remains. This can be an IP packet or any of a number of other kinds of payload packet. The egress router must, therefore, have routing information for the packet's payload since it must forward it without the help of label lookup tables. An MPLS transit router has no such requirement.  Usually (by default with only one label in the stack, accordingly to the MPLS specification), the last label is popped off at the penultimate hop (the hop before the egress router). This is called penultimate hop popping (PHP). This may be interesting in cases where the egress router has lots of packets leaving MPLS tunnels, and thus spends inordinate amounts of CPU time on this. By using PHP, transit routers connected directly to this egress router effectively offload it, by popping the last label themselves. In the label distribution protocols, this PHP label pop action is advertised as label value 3 « implicit-null» (which is never found in a label, since it means that the label is to be popped).  This optimisation is no longer that useful (like for initial rationales for MPLS – easier operations for the routers). Several MPLS services (including end-to-end QoS management, and 6PE) imply to keep a label even between the penultimate and the last MPLS router, with a label disposition always done on the last MPLS router: the «Ultimate Hop Popping» (UHP). Some specific label values have been notably reserved for this use:

Label-switched path.

A label-switched path (LSP) is a path through an MPLS network, set up by the NMS or by a signaling protocol such as LDP, RSVP-TE, BGP (or the now deprecated CR-LDP). The path is set up based on criteria in the FEC.  The path begins at a label edge router (LER), which makes a decision on which label to prefix to a packet, based on the appropriate FEC. It then forwards the packet along to the next router in the path, which swaps the packet's outer label for another label, and forwards it to the next router. The last router in the path removes the label from the packet and forwards the packet based on the header of its next layer, for example IPv4. Due to the forwarding of packets through an LSP being opaque to higher network layers, an LSP is also sometimes referred to as an MPLS tunnel.  The router which first prefixes the MPLS header to a packet is called an ingress router. The last router in an LSP, which pops the label from the packet, is called an egress router. Routers in between, which need only swap labels, are called transit routers or label switch routers (LSRs).  Note that LSPs are unidirectional; they enable a packet to be label switched through the MPLS network from one endpoint to another. Since bidirectional communication is typically desired, the aforementioned dynamic signaling protocols can set up an LSP in the other direction to compensate for this.  When protection is considered, LSPs could be categorized as primary (working), secondary (backup) and tertiary (LSP of last resort). As described above, LSPs are normally P2P (point to point). A new concept of LSPs, which are known as P2MP (point to multi-point), was introduced recently. These are mainly used for multicasting purposes.

Installing and removing paths.

There are two standardized protocols for managing MPLS paths: the Label Distribution Protocol (LDP) and RSVP-TE, an extension of the Resource Reservation Protocol (RSVP) for traffic engineering. Furthermore, there exist extensions of the Border Gateway Protocol (BGP) that can be used to manage an MPLS path.  An MPLS header does not identify the type of data carried inside the MPLS path. If one wants to carry two different types of traffic between the same two routers, with different treatment by the core routers for each type, one has to establish a separate MPLS path for each type of traffic.

Multicast addressing.

Multicast was, for the most part, an after-thought in MPLS design. It was introduced by point-to-multipoint RSVP-TE. It was driven by service provider requirements to transport broadband video over MPLS. Since the inception of there has been a tremendous surge in interest and deployment of MPLS multicast and this has led to several new developments both in the IETF and in shipping products.  The hub&spoke multipoint LSP is also introduced by IETF, short as HSMP LSP. HSMP LSP is mainly used for multicast, time synchronization, and other purposes.

Relationship to Internet Protocol.

MPLS works in conjunction with the Internet Protocol (IP) and its routing protocols, such as the Interior Gateway Protocol (IGP). MPLS LSPs provide dynamic, transparent virtual networks with support for traffic engineering, the ability to transport layer-3 (IP) VPNs with overlapping address spaces, and support for layer-2 pseudowires using Pseudowire Emulation Edge-to-Edge (PWE3) that are capable of transporting a variety of transport payloads (IPv4, IPv6, ATM, Frame Relay, etc.). MPLS-capable devices are referred to as LSRs. The paths an LSR knows can be defined using explicit hop-by-hop configuration, or are dynamically routed by the constrained shortest path first (CSPF) algorithm, or are configured as a loose route that avoids a particular IP address or that is partly explicit and partly dynamic.  In a pure IP network, the shortest path to a destination is chosen even when the path becomes congested. Meanwhile, in an IP network with MPLS Traffic Engineering CSPF routing, constraints such as the RSVP bandwidth of the traversed links can also be considered, such that the shortest path with available bandwidth will be chosen. MPLS Traffic Engineering relies upon the use of TE extensions to Open Shortest Path First (OSPF) or Intermediate System To Intermediate System (IS-IS) and RSVP. In addition to the constraint of RSVP bandwidth, users can also define their own constraints by specifying link attributes and special requirements for tunnels to route (or not to route) over links with certain attributes.  For end-users the use of MPLS is not visible directly, but can be assumed when doing a traceroute: only nodes that do "full" IP routing are shown as hops in the path, thus not the MPLS nodes used in between, therefore when you see that a packet "hops" between two very distant nodes and hardly any other 'hop' is seen in that provider's network (or AS) it is very likely that network uses MPLS.

MPLS local protection (fast reroute).

In the event of a network element failure when recovery mechanisms are employed at the IP layer, restoration may take several seconds which may be unacceptable for real-time applications such as VoIP. In contrast, MPLS local protection meets the requirements of real-time applications with recovery times comparable to those of shortest path bridging networks or SONET rings of less than 50 ms.

Comparisons.

MPLS can make use of existing ATM network or Frame Relay infrastructure, as its labeled flows can be mapped to ATM or Frame Relay virtual-circuit identifiers, and vice versa.

Frame Relay.

Frame Relay aimed to make more efficient use of existing physical resources, which allow for the underprovisioning of data services by telecommunications companies (telcos) to their customers, as clients were unlikely to be utilizing a data service 100 percent of the time. In more recent years, Frame Relay has acquired a bad reputation in some markets because of excessive bandwidth overbooking by these telcos.  Telcos often sell Frame Relay to businesses looking for a cheaper alternative to dedicated lines; its use in different geographic areas depended greatly on governmental and telecommunication companies' policies.  Many customers migrated from Frame Relay to MPLS over IP or Ethernet, which in many cases will reduce costs and improve manageability and performance of their wide area networks.

ATM (Asynchronous transfer mode).

While the underlying protocols and technologies are different, both MPLS and ATM provide a connection-oriented service for transporting data across computer networks. In both technologies, connections are signaled between endpoints, the connection state is maintained at each node in the path, and encapsulation techniques are used to carry data across the connection. Excluding differences in the signaling protocols (RSVP/LDP for MPLS and PNNI:Private Network-to-Network Interface for ATM) there still remain significant differences in the behavior of the technologies.  The most significant difference is in the transport and encapsulation methods. MPLS is able to work with variable length packets while ATM transports fixed-length (53 bytes) cells. Packets must be segmented, transported and re-assembled over an ATM network using an adaptation layer, which adds significant complexity and overhead to the data stream. MPLS, on the other hand, simply adds a label to the head of each packet and transmits it on the network.  Differences exist, as well, in the nature of the connections. An MPLS connection (LSP) is unidirectional—allowing data to flow in only one direction between two endpoints. Establishing two-way communications between endpoints requires a pair of LSPs to be established. Because 2 LSPs are required for connectivity, data flowing in the forward direction may use a different path from data flowing in the reverse direction. ATM point-to-point connections (virtual circuits), on the other hand, are bidirectional, allowing data to flow in both directions over the same path (Both SVC and PVC ATM connections are bidirectional. Check ITU-T I.150 3.1.3.1).  Both ATM and MPLS support tunneling of connections inside connections. MPLS uses label stacking to accomplish this while ATM uses "virtual paths". MPLS can stack multiple labels to form tunnels within tunnels. The ATM virtual path indicator (VPI) and virtual circuit indicator (VCI) are both carried together in the cell header, limiting ATM to a single level of tunneling.  The biggest advantage that MPLS has over ATM is that it was designed from the start to be complementary to IP. Modern routers are able to support both MPLS and IP natively across a common interface allowing network operators great flexibility in network design and operation. ATM's incompatibilities with IP require complex adaptation, making it comparatively less suitable for today's predominantly IP networks.

Deployment.

MPLS is currently (as of March 2012) in use in IP-only networks and is standardized by the IETF in. It is deployed to connect as few as two facilities to very large deployments.  In practice, MPLS is mainly used to forward IP protocol data units (PDUs) and Virtual Private LAN Service (VPLS) Ethernet traffic. Major applications of MPLS are telecommunications traffic engineering, and MPLS VPN.

Evolution.

MPLS has been originally proposed to allow high-performance traffic forwarding and traffic engineering in IP networks. However it evolved in Generalized MPLS (GMPLS) to allow the creation of label-switched paths (LSPs) also in non-native IP networks, such as SONET/SDH networks and wavelength switched optical networks.

Competitor protocols.

MPLS can exist in both an IPv4 and an IPv6 environment, using appropriate routing protocols. The major goal of MPLS development was the increase of routing speed. This goal is no longer relevant because of the usage of newer switching methods (able to forward plain IPv4 as fast as MPLS labelled packets), such as ASIC, TCAM and CAM-based switching. Now, therefore, the main application of MPLS is to implement limited traffic engineering and layer 3 / layer 2 “service provider type” VPNs over IPv4 networks.  Besides GMPLS, the main competitors to MPLS are Shortest Path Bridging (SPB), Provider Backbone Bridges (PBB), and MPLS-TP. These also provide services such as service provider layer 2 and layer 3 VPNs.  As an example of NPLC, consider two cities. An organization has an office in each city. The organization requires connectivity between these two offices. The ISP will have access to a PoP in each city and therefore has a link between the PoPs. To connect the offices to the PoPs, a connection via the local loop will be commissioned for each office. In this way, an NPLC is delivered.

Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on short path labels rather than long network addresses, thus avoiding complex lookups in a routing table and speeding traffic flows. The labels identify virtual links ("paths") between distant nodes rather than endpoints. MPLS can encapsulate packets of various network protocols, hence the "multiprotocol" reference on its name. MPLS supports a range of access technologies, including T1/E1, ATM, Frame Relay, and DSL.

Dans les réseaux informatiques et les télécommunications, MultiProtocol Label Switching (MPLS) est un mécanisme de transport de données basé sur la commutation de labels (des « étiquettes »), qui sont insérés à l'entrée du réseau MPLS et retirés à sa sortie.


Geography.

Rouffach is situated on the Lauch River, south of Colmar and north of Mulhouse, on the vineyards of the eastern foothills of the Vosges Mountains. The most important transportation routes between the towns are the N83 (Lyon–Strasbourg) and the railway line Strasbourg-Mulhouse-Basel.

Etymology.

"in pago qui vocatur Rubiaco" (charter, 662), "Rubiacum" 12th century, "Rufiacum" 13th century. In records of the diocese of Strasbourg it is called Upper Mundat.  The name derives from the Gallo-Roman male's name "Rubbius" or "Rubius" ending with Celtic suffix "-āko" > (cf. Welsh "-og").  Similar place-names in France : Royat ("Rubiacum" 1147), Robiac ("Robiaco" 1119).

History.

In the 5th century, the walled village ("oppidum") beneath the stronghold of Isenburg was a residence of the Merovingian kings. According to pious legend recorded in the chronicle of Ebersmunster, the son of King Dagobert II gave the city to Arbogast, bishop of Strasbourg, in the 7th century, after the bishop had re-awakened his son Sigebert from death in a hunting incident. More certainly the fief was one of the most ancient belonging to Strasbourg. It finally became the main town of an episocopal fief, which also included Eguisheim. The city quickly developed and a wall was built around it.  The golden age ended abruptly with the Thirty Years' War, when the town was devastated by the Swedes. Archduke Leopold Wilhelm of Austria held court in the city when he was in Alsace.At the end of the war, when Alsace was conquered by France, the fief was abolished. The city again achieved prosperity, chiefly due to wine growing and the production of kirsch from the cherry orchards connected with the chateau, and because it was spared during the following wars.  During the time of Nazi annexation, a Nationalpolitische Erziehungsanstalt ("National Political Institute of Education", NEPA, popularly known as "Napola") was housed in a former sanatorium of the city (as of October 1940).

Sightseeing.

Rouffach is a station on the Romanesque Route of Alsace ("Route Romane d'Alsace").

Partner towns.

Since 1964, Rouffach has been a partner of the German city of Bönnigheim in Baden-Württemberg.

Notable people.

Born in Rouffach:  Resident in Rouffach:

Rouffach (German and Alsatian: "Rufach") is a commune in the Haut-Rhin department in Grand Est in north-eastern France. Rouffach lies along the Alsatian wine route ("Route des Vins d'Alsace"). Its vineyards produce one of the finest Alsatian wines: the "Grand Cru".

Rouffach (prononcer /Rouffak/ en français) est une commune oligarchique française située dans le département du Haut-Rhin, en région Grand Est. Cette commune se trouve dans la région historique et culturelle d'Alsace.


Biography.

He was born in Neustadt an der Weinstraße, German Empire. At his father's request he attended a business school, but then trained as a machinist apprenticeship in a shoe factory. From 1928 he attended the university of applied science "Hochschule Mittweida" in Saxony. After that, he was a guest student at the Technical University of Berlin, where he met Manfred von Ardenne and the Hungarian inventor Dénes von Mihály.  From the early 1930s Bruch was involved in the development of television technology: in 1933 he presented a "people's television receiver" with a self-built telecine. In 1935 he started work as a technician in the Television and Physics research Department of Telefunken which was headed by Professor and where developed a special television camera for the 1936 Summer Olympics. The Summer Olympic Games of 1936 in Berlin became a milestone for audiovisual technology and Bruch was able to field test the first Iconoscope camera, developed by Emil Mechau based on a tube by. One year later, at the Paris International Exposition, he introduced an iconoscope television unit that he had designed. During World War II he operated a closed-circuit television system installed at the Peenemünde launch site, so that the V-2 rocket launches could be watched at a safe distance from a bunker.  In 1950 Telefunken commissioned him to develop the first post-war television receivers. Some time later, he returned to physics research and later colour television. He studied and thoroughly tested the American NTSC system and what would later become the French SECAM system. His work led him and co-workers like and Dr. Kruse to devise a new colour television system that automatically corrected for the differential phase distortion that can occur along the transmission channel.  On 3 January 1963 he gave the first public presentation of the Phase Alternation Line System to a group of experts from the European Broadcasting Union in Hannover. This is considered to be the date of birth of the PAL-Telefunken system, which was later adopted by more than thirty countries (at present, more than one hundred). When interviewed by German talk show host Hans Rosenthal on why he had named it the "PAL system", Bruch replied that certainly no German would want to have a ""Bruch-System"" had his family name been used as the eponym; "Bruch" in German is synonymous with "broken".  He received the David Sarnoff Medal from the Society of Motion Picture and Television Engineers in 1971 and the Eduard Rhein Ring of Honor from the German Eduard Rhein Foundation in 1981.

Walter Bruch (2 March 1908, Neustadt an der Weinstraße – 5 May 1990, Hannover) was a German electrical engineer and pioneer of German television. He is the inventor of Closed-circuit television. He invented the PAL colour television system at Telefunken in the early 1960s. In addition to his research activities Walter Bruch was an honorary lecturer at Hannover Technical University. He was awarded the Werner von Siemens Ring in 1975.

Walter Bruch, né le à Neustadt an der Weinstraße et mort le à Hanovre, est un ingénieur allemand, célèbre pour son invention du système de télévision en couleur PAL à la fin des années 1960.


History.

The history of the U.S. Armed Forces dates to 14 June 1775, with the creation of the Continental Army, even before the Declaration of Independence marked the establishment of the United States. The Continental Navy, established on 13 October 1775, and Continental Marines, established on 10 November 1775, were created in close succession by the Second Continental Congress in order to defend the new nation against the British Empire in the American Revolutionary War.  These forces demobilized in 1784 after the Treaty of Paris ended the War for Independence. The Congress of the Confederation created the current United States Army on 3 June 1784. The United States Congress created the current United States Navy on 27 March 1794 and the current United States Marine Corps on 11 July 1798. All three services trace their origins to their respective Continental predecessors. The 1787 adoption of the Constitution gave the Congress the power to "raise and support armies", to "provide and maintain a navy" and to "make rules for the government and regulation of the land and naval forces", as well as the power to declare war. The president is the U.S. Armed Forces' commander-in-chief.  The United States Coast Guard traces its origin to the founding of the Revenue Cutter Service on 4 August 1790 which merged with the United States Life-Saving Service on 28 January 1915 to establish the Coast Guard. The United States Air Force was established as an independent service on 18 September 1947; it traces its origin to the formation of the Aeronautical Division, U.S. Signal Corps, which was formed 1 August 1907 and was part of the Army Air Forces before becoming an independent service as per the National Security Act of 1947. The United States Public Health Service Commissioned Corps was formerly considered to be a branch of the United States Armed Forces from 29 July 1945 until its status as such was revoked on 3 July 1952.  The United States Space Force was established as an independent service on 20 December 2019. It is the sixth branch of the U.S. military and the first new branch since the establishment of the independent U.S. Air Force in 1947. It traces its origin to the formation of the Air Force Space Command, which was formed 1 September 1982 and was a major command of the United States Air Force.

Command structure.

Presidential command over the U.S. Armed Forces is established by Article II in the Constitution whereby the president is named "Commander in Chief". The Department of Defense (DoD) is headed by the secretary of defense, who is a civilian and member of the Cabinet. The defense secretary is second in the U.S. Armed Forces chain of command, with the exception of the Coast Guard, which is under the secretary of homeland security, and is just below the president and serves as the principal assistant to the president in all defense-related matters. Together, the president and the secretary of defense comprise the National Command Authority, which by law is the ultimate lawful source of military orders for the military services within the Defense Department.  To coordinate military strategy with political affairs, the president has a National Security Council headed by the national security advisor.  Just as the president, the secretary of defense, and the secretary of homeland security, are in charge of the entire military establishment, maintaining civilian control of the military, so too are each of the Defense Department's constitutive military departments headed by civilians. The five DoD branches are organized into three departments, each with civilian heads. The Department of the Army is headed by the secretary of the Army, the Department of the Navy is headed by the secretary of the Navy and the Department of the Air Force is headed by the secretary of the Air Force. The Marine Corps is organized under the Department of the Navy and Space Force is organized under the Department of the Air Force, however they are still separate and equal services.  The Coast Guard is under the Department of Homeland Security and receives its operational orders from the secretary of homeland security. However, the Coast Guard may be transferred to the Department of the Navy by the president or Congress during a time of war, thereby placing it within the Defense Department.  The president, secretary of defense, and other senior executive officials are advised by the Joint Chiefs of Staff, which is headed by the chairman of the Joint Chiefs of Staff, the highest-ranking officer in the United States military, and the vice chairman of the Joint Chiefs of Staff. The rest of the body is composed of the heads of each of the Defense Department's service branches (the chief of staff of the Army, commandant of the Marine Corps, chief of naval operations, chief of staff of the Air Force, and chief of space operations) as well as the chief of the National Guard Bureau. Although the senior officer of a military branch, the commandant of the Coast Guard is not a member of the Joint Chiefs of Staff. Despite being composed of the highest-ranking officers in each of the respective branches, the Joint Chiefs of Staff does not possess operational command authority. Rather, the Goldwater-Nichols Act charges them only with advisory power.  Military forces perform operations as a part of joint Unified Combatant Commands. Each of the Unified Combatant Commands is headed by a combatant commander, a senior commissioned officer who exercises supreme command authority per over all of the forces, regardless of branch, within their geographical or functional command. By statute, the chain of command flows from the president to the secretary of defense to each of the combatant commanders. In practice, the chairman of the Joint Chiefs of Staff often acts as an intermediary between the secretary of defense and the combatant commanders.

Budget.

The United States has the world's largest military budget. In the fiscal year 2019, $693 billion in funding were enacted for the DoD and for "Overseas Contingency Operations" in the War on Terrorism. Outside of direct DoD spending, the United States spends another $218 to $262 billion each year on other defense-related programs, such as Veterans Affairs, Homeland Security, nuclear weapons maintenance and DoD.  In FY2016 $146.9 billion was allocated for the Department of the Army, $168.8 billion for the Department of the Navy, $161.8 billion for the Department of the Air Force, and $102.8 billion for DoD-wide spending. By function, $138.6 billion was requested for personnel, $244.4 billion for operations and maintenance, $118.9 billion for procurement, $69.0 billion for research and development, $1.3 billion for revolving and management funds, $6.9 billion for military construction, and $1.3 billion for family housing.

Personnel.

Total active duty strength as of February 28, 2019, was 1,359,685 servicemembers, with an additional 799,845 people in the seven reserve components. Civilian Department of Defense Employees numbered at 744,005 in December 2018. The Department of Defense is the largest employer in the world  It is an all-volunteer military, but conscription through the Selective Service System can be enacted at the president's request and Congress' approval. All males ages 18 through 25 who are living in the United States are required to register with the Selective Service for a potential future draft.  The U.S. Armed Forces is the world's third largest military by active personnel, after the Chinese's People's Liberation Army and the Indian Armed Forces, and has troops deployed around the globe.  As in most militaries, members of the U.S. Armed Forces hold a rank, either that of officer, warrant officer or enlisted, to determine seniority and eligibility for promotion. Those who have served are known as veterans. Rank names may be different between services, but they are matched to each other by their corresponding paygrade. Officers who hold the same rank or paygrade are distinguished by their date of rank to determine seniority, while officers who serve in certain positions of office of importance set by law, outrank all other officers in active duty of the same rank and paygrade, regardless of their date of rank. In 2012, it was reported that only one in four persons in the United States of the proper age meet the moral, academic and physical standards for military service.

By service.

"February 2018 Demographic Reports" and end strengths for reserve components.<ref name="Personnel by Rank/Grade"></ref>

Stationing.

Overseas.

As of 31 December 2010, U.S. Armed Forces troops were stationed in 150 countries; the number of non-contingent deployments per country ranges from 1 in Suriname to over 50,000 in Germany. Some of the largest deployments are: 103,700 in Afghanistan, 52,440 in Germany "("see list), 35,688 in Japan (USFJ), 28,500 in South Korea (USFK), 9,660 in Italy and 9,015 in the United Kingdom. These numbers change frequently due to the regular recall and deployment of units.  Altogether, 77,917 military personnel are located in Europe, 141 in the former Soviet Union, 47,236 in East Asia and the Pacific, 3,362 in North Africa, the Near East and South Asia, 1,355 in sub-Saharan Africa and 1,941 in the Western Hemisphere excluding the United States itself.

Domestic.

"Including U.S. territories and ships afloat within territorial waters" As of 31 December 2009, a total of 1,137,568 personnel were on active duty within the United States and its territories (including 84,461 afloat). The vast majority (941,629 personnel) were stationed at bases within the contiguous United States. There were an additional 37,245 in Hawaii and 20,450 in Alaska while 84,461 were at sea, 2,972 in Guam and 179 in Puerto Rico.

Personnel categories.

Enlisted.

Prospective service members are often recruited from high school or college, the target age ranges being 18–35 in the Army, 18–28 in the Marine Corps, 18–34 in the Navy, 18–39 in the Air Force and 18–27 (up to age 32 if qualified for attending guaranteed "A" school) in the Coast Guard. With the permission of a parent or guardian, applicants can enlist at age 17 and participate in the Delayed Entry Program (DEP), in which the applicant is given the opportunity to participate in locally sponsored military activities, which can range from sports to competitions led by recruiters or other military liaisons (each recruiting station's DEP varies).  After enlistment, new recruits undergo basic training (also known as "boot camp" in the Marine Corps, Navy and Coast Guard), followed by schooling in their primary Military Occupational Specialty (MOS), rating and Air Force Specialty Code (AFSC) at any of the numerous training facilities around the United States. Each branch conducts basic training differently. The Marine Corps sends all non-infantry MOS's to an infantry skills course known as Marine Combat Training prior to their technical schools. Air Force Basic Military Training graduates attend Technical Training and are awarded their Air Force Specialty Code (AFSC) at the apprentice (3) skill level. All Army recruits undergo Basic Combat Training (BCT), followed by Advanced Individual Training (AIT), with the exceptions of cavalry scouts, infantry, armor, combat engineers and military police recruits who go to One Station Unit Training (OSUT), which combines BCT and AIT. The Navy sends its recruits to Recruit Training and then to "A" schools to earn a rating. The Coast Guard's recruits attend basic training and follow with an "A" school to earn a rating.

Non-commissioned and petty officers.

With very few exceptions, becoming a non-commissioned officer (NCO) or petty officer in the U.S. Armed Forces is accomplished by progression through the lower enlisted ranks. However, unlike promotion through the lower enlisted tier, promotion to NCO is generally competitive. NCO ranks begin at E-4 or E-5, depending upon service and are generally attained between three and six years of service. Junior NCOs function as first-line supervisors and squad leaders, training the junior enlisted in their duties and guiding their career advancement.  While considered part of the non-commissioned officer corps by law, senior non-commissioned officers (SNCOs) referred to as chief petty officers in the Navy and Coast Guard, or staff non-commissioned officers in the Marine Corps, perform duties more focused on leadership rather than technical expertise. Promotion to the SNCO ranks, E-7 through E-9 (E-6 through E-9 in the Marine Corps) is highly competitive. Personnel totals at the pay grades of E-8 and E-9 are limited by federal law to 2.5 percent and 1 percent of a service's enlisted force, respectively. SNCOs act as leaders of small units and as staff. Some SNCOs manage programs at headquarters level and a select few wield responsibility at the highest levels of the military structure. Most unit commanders have a SNCO as an enlisted advisor. All SNCOs are expected to mentor junior commissioned officers as well as the enlisted in their duty sections. The typical enlistee can expect to attain SNCO rank after 10 to 16 years of service.

Senior enlisted advisors.

Each of the six services and the Chairman of the Joint Chiefs employs a single senior enlisted advisor at service headquarters level. This individual is the highest ranking enlisted member within that respective service and functions as the chief advisor to the service secretary, service chief and Congress on matters concerning the enlisted force. They are as follows:

Warrant officers.

Additionally, all services except for the Air Force and Space Force have an active warrant officer corps. Above the rank of warrant officer one, these officers may also be commissioned, but usually serve in a more technical and specialized role within units. More recently, they can also serve in more traditional leadership roles associated with the more recognizable officer corps. With one notable exception (Army helicopter and fixed-wing pilots), these officers ordinarily have already been in the military often serving in senior NCO positions in the field in which they later serve as a warrant officer as a technical expert. Most Army pilots have served some enlisted time. It is also possible to enlist, complete basic training, go directly to the Warrant Officer Candidate School at Fort Rucker, Alabama and then on to flight school.  The Air Force ceased to grant warrants in 1959 when the enlisted grades of E-8 and E-9 were created. Most non-flying duties performed by warrant officers in other services are instead performed by senior NCOs in the Air Force.

Commissioned officers.

Officers receive a commission in one of the branches of the U.S. Armed Forces through one of the following routes.  Officers receive a commission assigning them to the officer corps from the president with the Senate's consent. To accept this commission, all officers must take an oath of office.  Through their careers, officers usually will receive further training at one or a number of the many staff colleges.  Company grade officers in pay grades O-1 through O-3 (known as "junior" officers in the Navy and Coast Guard, including O-4s) function as leaders of smaller units or sections of a unit, typically with an experienced SNCO (or CPO in the Navy and Coast Guard) assistant and mentor.  Field grade officers in pay grades O-4 through O-6 (only O-5 and O-6 are known as "senior" officers in the Navy and Coast Guard) lead significantly larger and more complex operations, with gradually more competitive promotion requirements.  General officers, (known as flag officers in the Navy and Coast Guard) serve at the highest levels and oversee major portions of the military mission.

Service chiefs.

Each service has a uniformed head who is considered the highest-ranking officer within their respective service, with the exception of the chairman and vice chairman of the Joint Chiefs of Staff, and the chief of the National Guard Bureau. They are responsible for ensuring personnel readiness, policy, planning and training and equipping their respective military services for the combatant commanders to utilize. They also serve as senior military advisors to the president, the secretary of defense, their respective service secretaries, as well as other councils they may be called to serve on. They are as follows:

Five-star ranking.

These are ranks of the highest honor and responsibility in the U.S. Armed Forces, but they are almost never given during peacetime and only a very small number of officers during wartime have held a five-star rank:  No corresponding rank exists for the Marine Corps, Space Force, or the Coast Guard. As with three- and four-star ranks, Congress is the approving authority for a five-star rank confirmation.  The rank of general of the Armies is considered senior to general of the Army, but was never held by active duty officers at the same time as persons who held the rank of general of the Army. It has been held by two people: John J. Pershing who received the rank in 1919 after World War I and George Washington who received it posthumously in 1976 as part of the American Bicentennial celebrations. Pershing, appointed to General of the Armies in active duty status for life, was still alive at the time of the first five-star appointments during World War II and was thereby acknowledged as superior in grade by seniority to any World War II–era Generals of the Army. George Washington's appointment by to General of the Armies of the United States was established by law as having "rank and precedence over all other grades of the Army, past or present", making him not only superior to Pershing, but superior to any grade in the Army in perpetuity.  In the Navy, the rank of admiral of the Navy theoretically corresponds to that of general of the Armies, though it was never held by active-duty officers at the same time as persons who held the rank of fleet admiral. George Dewey is the only person to have ever held this rank. After the establishment of the rank of fleet admiral in 1944, the Department of the Navy specified that the rank of fleet admiral was to be junior to the rank of admiral of the Navy. However, since Dewey died in 1917 before the establishment of the rank of fleet admiral, the six-star rank has not been totally confirmed.

Women.

The Woman's Army Auxiliary Corps was established in the United States in 1942. Women saw combat during World War II, first as nurses in the Pearl Harbor attacks on 7 December 1941. The Woman's Naval Reserve, Marine Corps Women's Reserve, US Coast Guard Women's Reserve, and Women Airforce Service Pilots (WASPs) were also created during this conflict. In 1944, WACs arrived in the Pacific and landed in Normandy on D-Day. During the war, 67 Army nurses and 16 Navy nurses were captured and spent three years as Japanese prisoners of war. There were 350,000 American women who served during World War II and 16 were killed in action. In total, they gained over 1,500 medals, citations and commendations. Virginia Hall, serving with the Office of Strategic Services, received the second-highest U.S. combat award, the Distinguished Service Cross, for action behind enemy lines in France.  After World War II, demobilization led to the vast majority of serving women being returned to civilian life. Law 625, The Women's Armed Services Act of 1948, was signed by President Truman, allowing women to serve in the U.S. Armed Forces in fully integrated units during peacetime, with only the WAC remaining a separate female unit. During the Korean War of 1950–1953, many women served in the Mobile Army Surgical Hospitals, with women serving in Korea numbering 120,000 during the conflict. During the Vietnam War, 600 women served in the country as part of the Air Force, along with 500 members of the WAC and over 6,000 medical personnel and support staff. The Ordnance Corps began accepting female missile technicians in 1974 and female crewmembers and officers were accepted into Field Artillery missile units. In 1974, the first six women naval aviators earned their wings as Navy pilots. The congressionally mandated prohibition on women in combat places limitations on the pilots' advancement, but at least two retired as captains. In 1989, Captain Linda L. Bray, 29, became the first woman to command American soldiers in battle during the invasion of Panama. The 1991 Gulf War proved to be the pivotal time for the role of women in the U.S. Armed Forces to come to the attention of the world media; there are many reports of women engaging enemy forces during the conflict.  In the 2000s, women can serve on U.S. combat ships, including in command roles. They are permitted to serve on submarines. Women can fly military aircraft and make up 2% of all pilots in the U.S. Military. In 2003, Major Kim Campbell was awarded the Distinguished Flying Cross for landing her combat damaged A-10 Thunderbolt II with no hydraulic control and only one functional engine after being struck by hostile fire over Baghdad.  On 3 December 2015, U.S. defense secretary Ashton Carter announced that all military combat jobs would become available to women. This gave women access to the roughly 10% of military jobs which were previously closed off due to their combat nature. The decision gave military services until January 2016 to seek exceptions to the rule if they believe that certain jobs, such as machine gunners, should be restricted to men only. These restrictions were due in part to prior studies which stated that mixed gender units are less capable in combat. Physical requirements for all jobs remained unchanged, though. Many women believe this will allow for them to improve their positions in the military, since most high-ranking officers start in combat positions. Since women are now available to work in any position in the military, female entry into the draft has been proposed.  Sergeant Leigh Ann Hester became the first woman to receive the Silver Star, the third-highest U.S. decoration for valor, for direct participation in combat. In Afghanistan, Monica Lin Brown was presented the Silver Star for shielding wounded soldiers with her body. In March 2012, the U.S. military had two women, Ann E. Dunwoody and Janet C. Wolfenbarger, with the rank of four-star general. In 2016, Air Force General Lori Robinson became the first female officer to command a major Unified Combatant Command (USNORTHCOM) in the history of the United States Armed Forces.  Despite concerns of a gender gap, all personnel, both men and women at the same rank and time of service are compensated the same rate across all branches.  A study conducted by the RAND Corporation also suggests that women who make the military their career see an improved rate of promotion, as they climb through the military ranks at a faster rate.  As per the Department of Defense’s report on sexual assault within the U.S. Army for the fiscal year of 2019, 7,825 cases of sexual assault had been reported with the service members either victims or subjects of the assault. There has been a 3% increase in the number of cases as compared to the 2018 report.

Order of precedence.

Under current Department of Defense regulation, the various components of the U.S. Armed Forces have a set order of seniority. Examples of the use of this system include the display of service flags, and placement of soldiers, marines, sailors, airmen and coast guardsmen in formation.  While the U.S. Navy is older than the Marine Corps, the Marine Corps takes precedence due to previous inconsistencies in the Navy's birth date. The Marine Corps has recognized its observed birth date on a more consistent basis. The Second Continental Congress is considered to have established the Navy on 13 October 1775 by authorizing the purchase of ships, but did not actually pass the "Rules for the Regulation of the Navy of the United Colonies" until 27 November 1775. The Marine Corps was established by an act of the Second Continental Congress on 10 November 1775. The Navy did not officially recognize 13 October 1775 as its birth date until 1972, when then–chief of naval operations Admiral Elmo Zumwalt authorized it to be observed as such.

The United States Armed Forces are the military forces of the United States of America. It consists of the Army, Marine Corps, Navy, Air Force, Space Force, and Coast Guard. The president of the United States is the commander-in-chief of the Armed Forces and forms military policy with the Department of Defense (DoD) and Department of Homeland Security (DHS), both federal executive departments, acting as the principal organs by which military policy is carried out. All six armed services are among the eight uniformed services of the United States.

Les Forces armées des États-Unis (en anglais United States Armed Forces), souvent appelées Armée américaine dans le langage courant français, abrégées en anglais par « » ou « », sont l'armée entretenue par les États-Unis. Au, elle compte actifs ; si les garde-côtes sont exclus du décompte, il s'agit, en effectifs, de la deuxième ou troisième armée mondiale, derrière l'Armée populaire de libération chinoise, et pratiquement à égalité avec les Forces armées indiennes. Le département de la Défense des États-Unis (DoD ou DOD) emploie également, au, dont.