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Stream cipher

A stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream. In a stream cipher, each plaintext digit is encrypted one at a time with the corresponding digit of the keystream, to give a digit of the ciphertext stream. Since encryption of each digit is dependent on the current state of the cipher, it is known as state cipher. In practice, a digit is a bit and the combining operation is an exclusive-or; the pseudorandom keystream is generated serially from a random seed value using digital shift registers. The seed value serves as the cryptographic key for decrypting the ciphertext stream. Stream ciphers represent a different approach to symmetric encryption from block ciphers. Block ciphers operate on large blocks of digits with a fixed, unvarying transformation; this distinction is not always clear-cut: in some modes of operation, a block cipher primitive is used in such a way that it acts as a stream cipher. Stream ciphers execute at a higher speed than block ciphers and have lower hardware complexity.

However, stream ciphers can be susceptible to serious security problems. Stream ciphers can be viewed as approximating the action of a proven unbreakable cipher, the one-time pad. A one-time pad uses a keystream of random digits; the keystream is combined with the plaintext digits one at a time to form the ciphertext. This system was proved to be secure by Claude E. Shannon in 1949. However, the keystream must be generated at random with at least the same length as the plaintext and cannot be used more than once; this makes the system cumbersome to implement in many practical applications, as a result the one-time pad has not been used, except for the most critical applications. Key generation and management are critical for those applications. A stream cipher makes use of a more convenient key such as 128 bits. Based on this key, it generates a pseudorandom keystream which can be combined with the plaintext digits in a similar fashion to the one-time pad. However, this comes at a cost; the keystream is now pseudorandom and so is not random.

The proof of security associated with the one-time pad no longer holds. It is quite possible for a stream cipher to be insecure. A stream cipher generates successive elements of the keystream based on an internal state; this state is updated in two ways: if the state changes independently of the plaintext or ciphertext messages, the cipher is classified as a synchronous stream cipher. By contrast, self-synchronising stream ciphers update their state based on previous ciphertext digits. In a synchronous stream cipher a stream of pseudo-random digits is generated independently of the plaintext and ciphertext messages, combined with the plaintext or the ciphertext. In the most common form, binary digits are used, the keystream is combined with the plaintext using the exclusive or operation; this is termed a binary additive stream cipher. In a synchronous stream cipher, the sender and receiver must be in step for decryption to be successful. If digits are added or removed from the message during transmission, synchronisation is lost.

To restore synchronisation, various offsets can be tried systematically to obtain the correct decryption. Another approach is to tag the ciphertext with markers at regular points in the output. If, however, a digit is corrupted in transmission, rather than added or lost, only a single digit in the plaintext is affected and the error does not propagate to other parts of the message; this property is useful. Moreover, because of this property, synchronous stream ciphers are susceptible to active attacks: if an attacker can change a digit in the ciphertext, he might be able to make predictable changes to the corresponding plaintext bit. Another approach uses several of the previous N ciphertext digits to compute the keystream; such schemes are known as self-synchronizing stream ciphers, asynchronous stream ciphers or ciphertext autokey. The idea of self-synchronization was patented in 1946, has the advantage that the receiver will automatically synchronise with the keystream generator after receiving N ciphertext digits, making it easier to recover if digits are dropped or added to the message stream.

Single-digit errors are limited in their effect, affecting only up to N plaintext digits. An example of a self-synchronising stream cipher is a block cipher in cipher feedback mode. Binary stream ciphers are constructed using linear-feedback shift registers because they can be implemented in hardware and can be analysed mathematically; the use of LFSRs on their own, however, is insufficient to provide good security. Various schemes have been proposed to increase the security of LFSRs; because LFSRs are inherently linear, one technique for removing the linearity is to feed the outputs of several parallel LFSRs into a non-linear Boolean function to form a combination generator. Various properties of such a combining function are critical for ensuring the security of the resultant scheme, for example, in order to avoid correlation attacks. LFSRs are stepped regularly. One approach to introducing non-linearity is to have the LFSR clocked irregularly, controlled by the output of a second LFSR; such generators include the stop-and-go generator, the alternating

Stranded Nation

Stranded Nation: White Australia in an Asian Region is a nonfiction book written by David Walker, a scholar of Australian images of Asia. It is a sequel to Anxious Nation, it explores the evolution of Australia's engagement with Asia during World War II and in the post-war period to the 1980s Walker argues that Australia's place in Asia has been at the forefront of public discussion and controversy since the mid 19th century. Australians imagined themselves as being a ‘white’ nation surrounded by hoards of'Asiatics' whose magnitude and foreignness threatened the existence of Australia's European society. Australians believed that the support of other'white' nations the United Kingdom and the United States, was required to maintain their security in a hostile environment; as Britain withdrew into a closer relationship with Europe during and after World War II, Australians were forced to recognise an urgent need to come to an accommodation with Asia. This resulted in persistent calls for a better understanding of the "Asian psyche" and changes in the rhetoric and rationale supporting the White Australia Policy.

Through a range of government policies and schemes Australia sought to position itself as an Asia-friendly neighbour and not an arrogant white intruder. These schemes were cosmetic in nature and had limited effect while the White Australia Policy remained effective until the mid 1970s. Walker's argument draws on a wide range of sources including archival records and the personal stories of visitors to and from Asia including writers, merchants and diplomats. Popular fiction is examined including the stories of W E Johns' Biggles; these sources illustrate the complexity of Australia's response to a changing world in which concepts of race and white prestige were shaken and transformed by decolonisation. Stephen FitzGerald has described Stranded Nation as "a recommended read for anyone and students alike, seeking to know the history of Australia’s agonising over Asia. Stranded Nation is told with authority and wit, the satisfying readability of a goodnovel, that makes it great history."On April 24, 2019 the book was discussed by Professor Walker and Richard Fidler on the ABC radio program Conversations.

Https://uwap.uwa.edu.au/products/stranded-nation

Liberty! (album)

Liberty! is an album by Mark O'Connor, which comprises his soundtrack to the six-part PBS series Liberty!. The album is composed of period songs arranged by O'Connor, with the exception of "Freedom" and the theme for the series, written by O'Connor, entitled "Song of the Liberty Bell". All tracks except for "Freedom" were written by Mark O'Connor. "Song of the Liberty Bell" – 5:45 "Johnny Has Gone for a Soldier" – 2:56 "Surrender the Sword" – 9:24 "Soldier's Joy" – 4:06 "When Bidden to the Wake or Fair" – 7:08 "The World Turned Upside Down" – 2:45 "Bunker Hill" – 5:43 "Freedom" – 3:40 "The Flowers of Edinburgh" – 4:15 "Brave Wolfe" – 6:47 "Devil's Dream" – 3:27 "Song of the Liberty Bell" – 6:45 Mark O'Connor - Violin James Taylor - Vocals, Guitar Yo-Yo Ma - Cello Wynton Marsalis - Trumpetalso: Mark O'Connor - Producer Laraine Perri - Executive Producer Dave Sinko, Charles Harbutt, Eric Prestige - Engineers Glenn Spinner, Tracy Hackney, Mark Wessel, Paul Falcone - Assistant Engineers Dave Sinko, Richard King - Mix Engineers Mark O'Connor - Editing and Additional Mixing

Kei Koizumi

Kei Koizumi is a Japanese football player who plays for Kashima Antlers in the J1 League. He is a central midfielder but can play at full-back. Koizumi started his career as a junior player with Yokohama F. Marinos, but the club did not promote him to their Under-18 team, he started playing for the school. He subsequently became a regular in the school team that won the Prince Takamado Cup in 2013. In 2014, Koizumi joined J. League Division 1 club Albirex Niigata and has added some versatility to the Albirex squad, his ability to play in a number of positions across defence and midfield made him an attractive proposition and boss Masaaki Yanagishita was delighted to be able to prise him away from The Big Swan Stadium. Updated to 12 January 2018. Profile at Albirex Niigata Kei Koizumi at J. League Kei Koizumi at Soccerway

2012 FIFA Futsal World Cup

The 2012 FIFA Futsal World Cup was the seventh FIFA Futsal World Cup, the quadrennial international futsal championship contested by the men's national teams of the member associations of FIFA. It took place from 1 to 18 November 2012 in Thailand. An extra four teams were competing at this World Cup; this was the first FIFA men's tournament held in Southeast Asia since the Malaysia 1997 FIFA World Youth Championship, was the first FIFA men's tournament held in the country, having hosted the 2004 FIFA U-19 Women's World Championship. Defending champions Brazil won the title for the fifth time, defeating Spain in a rematch of the 2008 final. Thailand beat bids from China, Azerbaijan, Czech Republic, Sri Lanka and Guatemala; the host nation, qualified automatically. The matches were due to take place across four venues. Due to construction delays and failure to meet the security requirement, early matches scheduled at the Bangkok Futsal Arena were moved to the Indoor Stadium Huamark. After the final inspection on 5 November, FIFA announced that the Bangkok Futsal Arena had not sufficiently met the criteria.

The two quarter-final matches would be played at Nimibutr Stadium, while Indoor Stadium Huamark would host the semifinals and the final. Each team submitted a squad of 14 players, including two goalkeepers; the squads were announced on 25 October 2012. The following were the officials for the 2012 FIFA Futsal World Cup; the official draw for the World Cup was held at the St. Regis Hotel in Bangkok, Thailand on 24 August 2012; the 24 teams were divided in each group with four teams. The group winners and runners up along with the 4 highest rank third places advanced to the round of 16; the ranking of each team in each group will be determined as follows: greatest number of points obtained in all group matches. All times are Thailand Standard Time. In the knockout stages, if a match is level at the end of normal playing time, extra time shall be played and followed, if necessary, by kicks from the penalty mark to determine the winner. However, for the third place match, no extra time shall be played and the winner shall be determined by kicks from the penalty mark.

9 goals Eder Lima8 goals Rodolfo Fortino7 goals 6 goals Jé5 goals 4 goals 3 goals 2 goals 1 goal Own goals Jhonathan Toro Jairo Toruño Saad Assis Alemao The following awards were given for the tournament: Per statistical convention in football, matches decided in extra time are counted as wins and losses, while matches decided by penalty shoot-out are counted as draws. The official song of 2012 FIFA Futsal World Cup was "Heart & Soul", a single by the Thai band Slot Machine. FIFA Futsal World Cup Thailand 2012, FIFA.com FIFA Technical Report

Michael Pointer (character)

Michael Pointer is a fictional character code-named Omega, a mutant appearing in American comic books published by Marvel Comics. He first appeared in New Avengers #16 as the Collective before becoming a member of the Omega Flight team. Pointer worked as a postman in North Pole, not knowing he was a mutant with the ability to absorb the energy and personalities of other mutants, he inadvertently became the focal point of the mutant energy displaced after the Decimation event, which had hovered above Earth, maintaining the disembodied mind of the deceased mutant Xorn, amongst others. After absorbing the energy, Pointer became the being known as the Collective. With his body possessed by Xorn's consciousness, Pointer went on a rampage across North America, killing over 2,000 people. Upon entering Canada, the Collective killed most of the original members of Alpha Flight. In Cleveland, outside the Rock and Roll Hall of Fame, he faced Iron Man, Ms. Marvel and the Sentry in battle. Through that encounter, Spider-Man and the Vision, with the assistance of S.

H. I. E. L. D. Were able to determine the nature of his powers; the Collective went to Genosha and began to transfer its powers to the depowered Magneto. After the ensuing battle between Magneto and the Collective and the New Avengers, Pointer still possessed a large amount of residual energy. After the super-hero Civil War, he was forced to join Omega Flight as a means of atoning for the damage he caused while being the Collective; as a member of Omega Flight, Pointer wore a suit designed by Reed Richards to regulate his mutant absorption powers. During Omega Flight's first mission, Pointer aided the group against the combined forces of the Wrecking Crew and the Great Beast known as Tanaraq. After the battle, Sasquatch apologizes for forcing Richard's suit onto Michael, instructing him to avoid dwelling on the past and to instead do right by the Guardian-styled uniform and the nation it represents. Pointer gains the forgiveness of Talisman, who realizes Pointer is remorseful for the indirect role he played in the Alpha Flight incident.

Under the code name of Weapon Omega, Pointer next appeared in the ongoing Marvel Comics Presents series, which lasted 12-issues. The Canadian government was using Pointer in a Weapon Omega project, in which villains captured by Omega Flight were used to provide Pointer with energy, as his Collective energy was beginning to trail off; the source of the energy was unknown to the other members of Omega Flight. The government would use Mutant Growth Hormone to pump up the criminals' powers and make their DNA more compatible to Pointer's, while using the Guardian suit to regulate the flow; this caused Pointer to become an addict of the energy, only with the help of the other members of Omega Flight was he able to put a stop to the government plans. At the end of this series he rejected his role in Omega Flight, he appeared in Incredible Hercules #117 in a flashback scene where he asked Snowbird to join Omega Flight. She violently refused, since he killed her former teammates as the Collective and was now wearing a suit similar to the original Guardian's uniform.

Weapon Omega was recruited to join Emma Frost's "Dark X-Men". Norman Osborn gets Omega to join his X-Men to'atone' for all the deaths. Osborn attempts to use a device created by Dark Beast to siphon powers away from mutants and place them into Pointer. Pointer seems to develop an addiction to this yelling that he needs "more juice" during his power ups from the device. Pointer's uniform stopped looking like the Guardian suit and he would drop Weapon from his code name. After the reshuffle of Osborn's X-Men, the power-ups are shown to be affecting Pointer's psyche where it seems remnants of the personalities of the mutants he is draining energy from seep into his mind. After Osborn was taken down by the Avengers during the Siege storyline and Weapon Omega left H. A. M. M. E. R, but Weapon Omega's powers started acting up. Mimic went to Hank McCoy for help, as he had been the only person who had always aided him when he needed help. Mimic took Weapon Omega to the Xavier Institute where Beast found out that Weapon Omega was about to explode.

The X-Men tried various ways to prevent the explosion. But in the end, the only way left. Weapon Omega asked his only friend to do it and Mimic complied. Borrowing powers from Rachel Grey, Mimic put Omega to sleep promising to stay by his side until he wakes up. Michael Pointer is a mutant with the ability to absorb the energy and abilities of other mutants, he does not need touch. His absorption results in a commensurate loss of ability in his victims, he wears a suit designed to focus absorbed energies into flight and energy blasts, but would otherwise demonstrate the same mutant powers he has absorbed. He is limited by guilt, inexperience with various mutant powers, a lack of confidence and the confusion caused by absorbing strong personalities or many personalities; as the Collective, he contained the inherent power of every mutant on the planet. When Mimic copied Michael's absorption ability, the two of them were able to neutralize X-Man. AlphaFlight.net Alphanex Entry on Guardian IV