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Content Scramble System

The Content Scramble System is a digital rights management and encryption system employed on many commercially produced DVD-Video discs. CSS utilizes a proprietary 40-bit stream cipher algorithm; the system was introduced on October 29, 1996 and was first compromised in 1999. CSS is one of several complementary systems designed to restrict DVD-Video access, it has been superseded by newer DRM schemes such as Content Protection for Recordable Media, or by Advanced Encryption Standard in the Advanced Access Content System DRM scheme used by HD DVD and Blu-ray Disc, which have 56-bit and 128-bit key sizes providing a much higher level of security than the less secure 40-bit key size of CSS. The content scramble system is a collection of proprietary protection mechanisms for DVD-Video discs. CSS attempts to restrict access to the content only for licensed applications. According to the DVD Copy Control Association, the consortium that grants licenses, CSS is supposed to protect the intellectual property rights of the content owner.

The details of CSS are only given to licensees for a fee. The license, which binds the licensee to a non-disclosure agreement, wouldn't permit the development of open-source software for DVD-Video playback. Instead, there is libdvdcss, a reverse engineered implementation of CSS. Libdvdcss is a source for documentation, along with the publicly available DVD-ROM and MMC specifications. There has been some effort to collect CSS details from various sources. A DVD-Video can be produced with or without CSS; the publisher may for instance decide to go without CSS protection to save license and production costs. The content scramble system deals with three participants: the drive and the player; the disc holds the encrypted feature. The drive provides the means to read the disc; the player presents the audio and visual content of the feature. All participants must conform to the CCA's license agreement. There are three protection methods: Playback protection is based on encryption: the player requires a secret key to decrypt the feature.

Read protection is based on the drive: access to significant disc data is only granted if the player authenticates successfully. Regional restriction is based on the disc and the drive: the drive can deny access if the disc doesn't belong to the drive's region; the first two protection methods have been broken. Circumvention of regional protection is not possible with every drive -- if the drive grants access to the feature, prediction of title keys may fail. However, DVD players exist which do not enforce regional restrictions, which makes regional restrictions less effective as a component of CSS; the DVD-ROM's main-data, which are consecutive logical blocks of 2048 bytes, are structured according to the DVD-Video format. The DVD-Video contains an MPEG program stream. If CSS is applied to the disc a subset of all Packs is encrypted with a title-key. A DVD-ROM contains, besides the main-data, additional data areas. CSS stores there: a flag that indicates whether CSS is applied or not, the 8-bit region-management-information, a disc-key-block that holds 409 encrypted variants of the disc-key.

CSS uses six bytes in the frame header for each logical block of user data: one byte with copyright management information, five bytes holding an encrypted title-key. The drive treats a DVD-Video disc as any DVD-ROM disc; the player processes them according to the DVD-Video format. However, if the drive detects a disc, compiled with CSS, it denies access to logical blocks that are marked as copyrighted; the player has to execute an authentication handshake first. The authentication handshake is used to retrieve the disc-key-block and the title-keys; the drive may support Regional Playback Control to limit the playback of DVD-Video content to specific regions of the world. RPC Phase II drives hold an 8-bit region-code and adhere to all requirements of the CSS license agreement, it appears. However, reading of user-data may still work. CSS employs a stream cipher and mangles the keystream with the plain-text data to produce the cipher text; the stream cipher is set up with a 40-bit seed. Mangling depends on the type of operation.

There are three types: the decryption of a disc- or title-key, the decryption of a Pack and the encryption of keys for the authentication handshake. In order to decrypt a DVD-Video, the player reads the disc-key-block and uses its player-key to decrypt the disc-key. Thereafter, the player decrypts them with the disc-key. A different title-key can be assigned for each Video Title Set; the title-keys are used to decrypt the Packs. CSS employs cryptographic keys with a size of only 40 bits; this makes CSS vulnerable to a brute-force attack. At the time CSS was introduced, it was forbidden in the United States for manufacturers to export cryptographic systems employing keys in excess of 40 bits, a key length, shown to be wholly inadequate in the face of increasing computer processing power. Based on the leaked DeCSS source-code, Frank A. Stevenson published in November 1999 three exploits that rendered the CSS cipher ineffective: A correlation attack enables the recovery of a keystream's seed at complexity of 216.

The mangling of disc- and title-keys can be reversed at a complexity of 28. A

Satellite dish

A satellite dish is a dish-shaped type of parabolic antenna designed to receive or transmit information by radio waves to or from a communication satellite. The term most means a dish used by consumers to receive direct-broadcast satellite television from a direct broadcast satellite in geostationary orbit; the unicode character that depicts a satellite dish is U+1F4E1. The parabolic shape of a dish reflects the signal to the dish’s focal point. Mounted on brackets at the dish's focal point is a device called a feedhorn; this feedhorn is the front-end of a waveguide that gathers the signals at or near the focal point and'conducts' them to a low-noise block downconverter or LNB. The LNB converts the signals from electromagnetic or radio waves to electrical signals and shifts the signals from the downlinked C-band and/or Ku-band to the L-band range. Direct broadcast satellite dishes use an LNBF, which integrates the feedhorn with the LNB. A new form of omnidirectional satellite antenna, which does not use a directed parabolic dish and can be used on a mobile platform such as a vehicle was announced by the University of Waterloo in 2004.

The theoretical gain of a dish increases. The actual gain depends on many factors including surface finish, accuracy of shape, feedhorn matching. A typical value for a consumer type 60 cm satellite dish at 11.75 GHz is 37.50 dB. With lower frequencies, C-band for example, dish designers have a wider choice of materials; the large size of dish required for lower frequencies led to the dishes being constructed from metal mesh on a metal framework. At higher frequencies, mesh type designs are rarer though some designs have used a solid dish with perforations. A common misconception is that the LNBF, the device at the front of the dish, receives the signal directly from the atmosphere. For instance, one BBC News downlink shows a "red signal" being received by the LNBF directly instead of being beamed to the dish, which because of its parabolic shape will collect the signal into a smaller area and deliver it to the LNBF. Modern dishes intended for home television use are 43 cm to 80 cm in diameter, are fixed in one position, for Ku-band reception from one orbital position.

Prior to the existence of direct broadcast satellite services, home users would have a motorised C-band dish of up to 3 m in diameter for reception of channels from different satellites. Overly small dishes can still cause problems, including rain fade and interference from adjacent satellites. In Europe, the frequencies used by DBS services are 10.7–12.75 GHz on two polarisations H and V. This range is divided into a "low band" with 10.7–11.7 GHz, a "high band" with 11.7–12.75 GHz. This results in two frequency bands, each with a bandwidth of about 1 GHz, each with two possible polarizations. In the LNB they become down converted to 950–2150 MHz, the frequency range allocated for the satellite service on the coaxial cable between LNBF and receiver. Lower frequencies are allocated to FM radio, etc.. Only one of these frequency bands fits on the coaxial cable, so each of these bands needs a separate cable from the LNBF to a switching matrix or the receiver needs to select one of the 4 possibilities at a time.

In a single receiver residential installation there is a single coaxial cable running from the receiver set-top box in the building to the LNB on the dish. The DC electric power for the LNB is provided through the same coaxial cable conductors that carry the signal to the receiver. In addition, control signals are transmitted from the receiver to the LNB through the cable; the receiver uses different power supply voltages to select vertical / horizontal antenna polarization, an on/off pilot tone to instruct the LNB to select one of the two frequency bands. In larger installations each band and polarization is given its own cable, so there are 4 cables from the LNB to a'multiswitch' switching matrix, which allows the connection of multiple receivers to the multiswitch in a star topology using the same signalling method as in a single receiver installation. A satellite finder may aid in aiming the satellite dish. Professional satellite meters allow better dish alignment and provide received signal parameter values too.

A dish, mounted on a pole and driven by a stepper motor or a servo can be controlled and rotated to face any satellite position in the sky. Motor-driven dishes are popular with enthusiasts. There are three competing standards: DiSEqC, USALS, 36 V positioners. Many receivers support all of these standards; some designs enable simultaneous reception from multiple different satellite positions without re-positioning the dish. The vertical axis operates as an off-axis concave parabolic concave hyperbolic Cassegrain reflector, while the horizontal axis operates as a concave convex Cassegrain; the spot from the main dish wanders across the secondary, which corrects astigmatism by its varying curvature. The elliptic aperture of the primary is designed to fit the deformed illumination by the horns. Due to double spill-over, this makes more sense for a large dish. A common type of dish is the small aperture terminal; this provides two way satellite internet communications for both consumers and private networks for organizations.

Today most VSATs operate in Ku band. There is a move which started in 2005 towards new Ka band satellites operating at higher frequencies, offering greater performance at lower cost; these antennas vary from 74 to 120 cm in most applications though C-band VSATs may be as large as 4 m. Individual dishes s

Marc Ryan

Marc Ryan is a New Zealand racing cyclist. At the 2008 Summer Olympics in Beijing, Ryan won the bronze medal as part of the New Zealand team in team pursuit, together with Sam Bewley, Hayden Roulston, Jesse Sergent. At the 2009–2010 UCI Track Cycling World Cup Classics in Melbourne and Thomas Scully won the Men's Madison in a time of 44 minutes, 33 seconds, at an average speed of 53.9 km per hour. Second place went to the German riders, Robert Bengsch and Marcel Kalz, third place to Ukraine. At the 2012 London Olympics Ryan again won a bronze medal in the team pursuit, together with Jesse Sergent, Sam Bewley, Westley Gough and Aaron Gate

Stuart A. Robertson

Stuart A. Robertson was co-founder, with Wendell Milliman, of Milliman, Inc. Milliman & Robertson, which would grow to become one of the largest actuarial and business consulting firms in the world, encompassing more than 30 locations throughout the United States with offices in 16 other countries. Robertson, who attended the University of Washington before becoming an actuary, joined Milliman in the first consulting actuarial practice in the Pacific Northwest in 1950. Following Milliman's retirement in 1971, Robertson served as CEO and chairman until his retirement in 1983. Stuart Robertson was born on February 28, 1918, in Montesano, Wash. in Gray's Harbor County about 95 miles southwest of Seattle. The family was shaken when the father, a civil engineer, died just three months after Stuart's birth; because of their mother's efforts and working outside of school, all five children went to college. In 1934, Robertson at first entered the University of Idaho in Moscow, because of the low tuition.

But when he was told he must pay a higher out-of-state rate, he transferred to the University of Washington where he helped meet the costs of board and tuition by working part-time as a houseboy in a campus sorority and with a second job at the federally funded National Youth Administration. During summer breaks, he worked at a pea cannery. In his junior year at college, Robertson was reconsidering his future course when he saw a recruiting notice for actuaries on a bulletin board in the math department. After some research to find what an actuary did, he became intrigued. Milliman principal Stan Roberts once described actuaries as “doctors of probability,” in that their occupation involves calculating the likelihood of such things as how long an individual will live after retirement or how someone is to come down with a specific disease; these calculations are used by companies like insurance firms and financial institutions to calculate rates and decide what services to provide. From his research, Robertson learned that he could earn the status of Fellow in the Actuarial Institute by passing tests and decided this might better serve his goal than a bachelor's degree.

A day after his 19th birthday, he began a job as a clerk for the actuary at the Great Northwest Life Insurance Company in Spokane, Wash. He began studying for his first actuarial exam. From 1937 to 1947, he rose through the ranks at Great Northwest to become a vice president in the firm, he dealt with multiple aspects of insurance, including actuarial work, accounting and stockholder and policyholder relations. In 1939, he married childhood acquaintance Marjory Moch. In 1947, he returned to Seattle. At this point, anticipating his final actuarial exam, he began to consider a move to the East Coast to expand his prospects, but he met Wendell Milliman, who made the case for the potential of actuarial consulting. Milliman had established the first consulting actuarial practice in the Pacific Northwest in 1947, he worked for state government and firms that were too small to have their own actuarial departments. Robertson joined Milliman in his two-room office at 914 Second Avenue in Seattle, bringing Northwestern Life along as a client.

In one room, the two shared a phone and an enormous desk, with a top consisting of a five-foot-by-five-foot oak slab. The desk had “a full complement of drawers on either side,” Robertson recalled. Milliman and Robertson were so busy that they “spent little time conversing other than to say ‘pass the telephone.’"In addition to Northwestern Life, who by this time had experience working for small insurance firms, was assigned to work for eight or nine such clients. However, just six months after coming to work with Milliman, Robertson found himself in a novel situation. Wendell Milliman had been offered a job with a large Eastern firm, New York Life Insurance Company, to become a vice president in charge of organizing and administrating the firm's new group insurance department. While the pay—$25,000 per year—was good for 1950, it was the challenge that attracted him and he decided to go. Milliman offered to sell Robertson the firm and, though Robertson had concerns that he had no backup capital of his own, he accepted.

The terms included $1,000 up front and five yearly payments, which amounted to $9,630. Five years however, Milliman made a surprise visit to Robertson, at which point he asked if he would like a partner—namely one Wendell Milliman. Robertson agreed and soon they formed Milliman & Robertson. In 1957, the firm incorporated. By 1965, it had opened new offices in Los Angeles. At that point, Milliman & Robertson was the second largest actuarial firm in the country. Over the years and Robertson built on the firm's fundamentals. An entrepreneurial model gave principals the opportunity to invest in new expansion, either geographically or into new practice areas, enabled them to benefit from successes while taking on some of the risks; when Milliman retired in 1971, Robertson was named chairman of the firm. James Curtis became president. At the time, Robertson had been in the actuarial field for 30 years. In 1974, under his leadership, a peer-review process was adopted to check on the quality of work in real time.

In 1976, the firm reorganized. Colleagues praised Robertson for his contribution to the firm's professionalism and for a slight streak of conservatism that kept the firm on course, he p

Mathias Lauridsen

Mathias Lauridsen is a Danish model. He broke onto the international fashion scene debuting at Marc by Marc Jacobs in New York and Miu Miu in Paris, for the Spring 2004 collections, his consistent work for major international fashion brands and publications has solidified his status as a male supermodel. In 2014, Vogue listed him as one of the top 10 male models of all time. Lauridsen was discovered in 2003 and is signed with Ford Models in Paris, IMG in New York and Scoop in Copenhagen, he is considered to be one of the best male models, has landed many lucrative contracts, for example the Gucci Pour Homme II fragrance. His runway credentials include opening shows for Hermès, Jill Stuart and closing for Missoni, Gucci and John Galliano. Lauridsen has been featured in numerous major fashion campaigns including Prada, Jil Sander, Hugo Boss, Louis Vuitton, Christian Dior, Hermès, Calvin Klein, Marc Jacobs, DKNY, Tommy Hilfiger, Aldo, Bottega Veneta, Carolina Herrera, Emporio Armani, Cartier, Burberry, H&M, Salvatore Ferragamo, Nina Ricci, Massimo Dutti and Filippa K.

He has appeared in dozens of editorials for major fashion publications such as Vogue Italia, L'Uomo Vogue, Vogue Paris, Numéro Homme, numerous international editions of GQ and Details. Some of the photographers he has worked with include Mario Testino, Steven Meisel, Karl Lagerfeld, David Sims, Patrick Demarchelier, Craig McDean and Richard Avedon. Avedon photographed Lauridsen for a Hermes campaign in 2004 that proved to be one of the photographers last works, he was ranked number 1 on models.com Top 50 Male Models list for more than two years. Lauridsen was the youngest model, he is ranked #2 in the list of the most successful male models in the world, published by Forbes. As of July 2014, he's ranked in The Money Guys on Models.com. His distinguishing feature is a scar. IMG Models - New York City Premium Models - Paris Kult Model Agency - Hamburg Scoop Models - Copenhagen Avenue Modeller - Gothenburg Sight Management Studio - Barcelona Mother agency: Scoop Models Copenhagen See Mathias Lauridsen at: models.com and New York Magazine

Battle of Jarosław (1656)

The Battle of Jarosław took place during the Deluge in March 15, 1656. Polish-Lithuanian Commonwealth forces under the command of Stefan Czarniecki defeated the Swedish forces commanded by Charles X Gustav of Sweden. After the Battle of Golab, the Swedish army under King Charles X Gustav marched towards Lwow, where Polish forces concentrated, where King Jan Kazimierz stayed. In early March 1656, Charles X Gustav received news that up to 20,000 Polish-Lithuanian soldiers concentrated in Red Ruthenia; the Swedish King realized that his forces were not adequate to face the enemy, so he ordered a retreat towards the San river. Furthermore, the Swedes were attacked by Polish guerrilla forces. On March 11, first Swedish units reached the town of Jaroslaw, where they defeated a regiment of Hetman Jerzy Sebastian Lubomirski, which guarded the river crossings. Soon afterwards, the division of Stefan Czarniecki arrived in the area, surprising the Swedes, as they thought it had been destroyed in the Battle of Golab.

In a skirmish, which took place near Wielkie Oczy, Czarniecki destroyed a 1,000 strong unit of the reiters, commanded by Colonel Peter Hammerskjold. He attacked Robert Douglas, Count of Skenninge, who came to rescue the reitars; the skirmish ended in a Swedish defeat, Douglas with his soldiers fled to Jaroslaw. Soon afterwards, Czarniecki attacked the town itself, clashing with Swedish guards, who oversaw labourers working on improvements of the town fortifications. Since Charles Gustav was well aware of Czarniecki’s presence, he called reinforcements from units stationed in local villages. Arrival of main Swedish forces resulted in Polish retreat into the local forests; the battle, or rather the series of skirmishes, had a significant impact on those Polish units, which still remained loyal to Charles Gustav. After the battle, several such regiments abandoned the Swedes, while Charles Gustav came to the conclusion that a further march towards southeast was fruitless. A tactical retreat towards Sandomierz was ordered, soon afterwards, the Swedish army was encircled in the confluence of the San and the Vistula.

Leszek Podhorodecki: Rapier i koncerz. Warszawa: 1985. ISBN 83-05-11452-X. Tadeusz M. Nowak, Jan Wimmer: Historia oręża polskiego 963-1795. Warszawa: Wiedza Powszechna, 1981. ISBN 83-214-0133-3