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🔗 Computing 🔗 Computing/Computer Security 🔗 Computing/Networking

In computer networking, port knocking is a method of externally opening ports on a firewall by generating a connection attempt on a set of prespecified closed ports. Once a correct sequence of connection attempts is received, the firewall rules are dynamically modified to allow the host which sent the connection attempts to connect over specific port(s). A variant called single packet authorization (SPA) exists, where only a single "knock" is needed, consisting of an encrypted packet.

The primary purpose of port knocking is to prevent an attacker from scanning a system for potentially exploitable services by doing a port scan, because unless the attacker sends the correct knock sequence, the protected ports will appear closed.

🔗 Organizations 🔗 Fashion

The Rational Dress Society was an organisation founded in 1881 in London, part of the movement for Victorian dress reform. It described its purpose thus:

The Rational Dress Society protests against the introduction of any fashion in dress that either deforms the figure, impedes the movements of the body, or in any way tends to injure the health. It protests against the wearing of tightly-fitting corsets; of high-heeled shoes; of heavily-weighted skirts, as rendering healthy exercise almost impossible; and of all tie down cloaks or other garments impeding on the movements of the arms. It protests against crinolines or crinolettes of any kind as ugly and deforming... [It] requires all to be dressed healthily, comfortably, and beautifully, to seek what conduces to birth, comfort and beauty in our dress as a duty to ourselves and each other.

In the catalogue of its inaugural exhibition, it listed the attributes of "perfect" dress as:

1. Freedom of Movement.
2. Absence of pressure over any part of the body.
3. Not more weight than is necessary for warmth, and both weight and warmth evenly distributed.
4. Grace and beauty combined with comfort and convenience.
5. Not departing too conspicuously from the ordinary dress of the time.

Leading members of the Society were Lady Harberton (who created the divided skirt), Mary Eliza Haweis and Constance Wilde (Irish author). Oscar Wilde helped spread the word by publishing the essay "The Philosophy of Dress" in which he stressed the important relationship between clothing and one’s soul. Woman cyclists, such as members of the Lady Cyclists' Association, were keen advocates of women's right to dress appropriately for the activity, as part of a belief that cycling offered women an opportunity to escape overly restrictive societal norms.

In 1889, a member of the Rational Dress Society, Charlotte Carmichael Stopes, staged a coup at a meeting of the British Association for the Advancement of Science in Newcastle upon Tyne, when she arranged an impromptu addition to the programme on the subject of rational dress. Her speech was reported by newspapers across Britain and the notion of rational dress was the biggest news from the meeting.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Automobiles 🔗 Military history/World War II 🔗 Military history/German military history 🔗 Military history/European military history 🔗 Containers

A jerrycan (also written as jerry can or jerrican) is a robust liquid container made from pressed steel. It was designed in Germany in the 1930s for military use to hold 20 litres (4.4 imp gal; 5.3 US gal) of fuel. The development of the jerrycan was a significant improvement on earlier designs, which required tools and funnels to use, and it contained many innovative features for convenience of use and robustness. After widespread use by both Germany and the Allies during the Second World War, today similar designs are used worldwide for fuel and water containers, some of which are also produced in plastic. The designs usually emulate the original steel design and are still known as jerrycans. The original design of jerrycan and various derivatives remain in widespread military use.

🔗 Statistics 🔗 Sociology

The Anna Karenina principle states that a deficiency in any one of a number of factors dooms an endeavor to failure. Consequently, a successful endeavor (subject to this principle) is one where every possible deficiency has been avoided.

The name of the principle derives from Leo Tolstoy's book Anna Karenina, which begins:

All happy families are alike; each unhappy family is unhappy in its own way.

In other words: happy families share a common set of attributes which lead to happiness, while any of a variety of attributes can cause an unhappy family. This concept has been generalized to apply to several fields of study.

In statistics, the term Anna Karenina principle is used to describe significance tests: there are any number of ways in which a dataset may violate the null hypothesis and only one in which all the assumptions are satisfied.

🔗 Apple Inc./Macintosh 🔗 Apple Inc. 🔗 Apple Inc./Mac

The Command key (sometimes abbreviated as Cmd key), ⌘, formerly also known as the Apple key or open Apple key, is a modifier key present on Apple keyboards. The Command key's purpose is to allow the user to enter keyboard commands in applications and in the system. An "extended" Macintosh keyboard—the most common type—has two command keys, one on each side of the space bar; some compact keyboards have one only on the left.

The ⌘ symbol (the "looped square") was chosen by Susan Kare after Steve Jobs decided that the use of the Apple logo in the menu system (where the keyboard shortcuts are displayed) would be an over-use of the logo. Apple's adaptation of the symbol—encoded in Unicode at U+2318—was derived in part from its use in Nordic countries as an indicator of cultural locations and places of interest. The symbol is known by various other names, including "Saint John's Arms" and "Bowen knot".

🔗 France 🔗 Languages

Verlan (French pronunciation: ​[vɛʁlɑ̃]), (verlan is the reverse of the expression "l'envers") is a type of argot in the French language, featuring inversion of syllables in a word, and is common in slang and youth language. It rests on a long French tradition of transposing syllables of individual words to create slang words. The name verlan itself is an example: it is derived from inverting the sounds of the syllables in l'envers ([lɑ̃vɛʁ], "the inverse", frequently used in the sense of "back-to-front").

🔗 United States 🔗 Internet 🔗 Law 🔗 Freedom of speech 🔗 Law Enforcement 🔗 United States/FBI

A warrant canary is a method by which a communications service provider aims to inform its users that the provider has been served with a government subpoena despite legal prohibitions on revealing the existence of the subpoena. The warrant canary typically informs users that there has not been a court-issued subpoena as of a particular date. If the canary is not updated for the period specified by the host or if the warning is removed, users are to assume that the host has been served with such a subpoena. The intention is to allow the provider to warn users of the existence of a subpoena passively, without technically violating the court order not to do so.

Some subpoenas, such as those covered under 18 U.S.C. §2709(c) of the USA Patriot Act, provide criminal penalties for disclosing the existence of the subpoena to any third party, including the service provider's users.

National Security Letters (NSL) originated in the 1986 Electronic Communications Privacy Act and originally targeted those suspected of being agents of a foreign power. Targeting agents of a foreign power was revised in 2001 under the Patriot Act to allow NSLs to target those who may have information deemed relevant to both counterintelligence activities directed against the United States and terrorism. The idea of using negative pronouncements to thwart the nondisclosure requirements of court orders and served secret warrants was first proposed by Steven Schear on the cypherpunks mailing list, mainly to uncover targeted individuals at ISPs. It was also suggested for and used by public libraries in 2002 in response to the USA Patriot Act, which could have forced librarians to disclose the circulation history of library patrons.

🔗 Biography

Ward Christensen (born 1945 in West Bend, Wisconsin, United States) was the co-founder of the CBBS bulletin board, the first bulletin board system (BBS) ever brought online. Christensen, along with partner Randy Suess, members of the Chicago Area Computer Hobbyists' Exchange (CACHE), started development during a blizzard in Chicago, Illinois, and officially established CBBS four weeks later, on February 16, 1978. CACHE members frequently shared programs and had long been discussing some form of file transfer, and the two used the downtime during the blizzard to implement it.

Christensen was noted for building software tools for his needs. He wrote a cassette-based operating system before floppies and hard disks were common. When he lost track of the source code for some programs, he wrote ReSource, an iterative disassembler for the Intel 8080, to help him regenerate the source code. When he needed to send files to Randy Suess, he wrote XMODEM.

Jerry Pournelle wrote in 1983 of a collection of CP/M public-domain software that "probably 50 percent of the really good programs were written by Ward Christensen, a public benefactor." Christensen received two 1992 Dvorak Awards for Excellence in Telecommunications, one with Randy Suess for developing the first BBS, and a lifetime achievement award "for outstanding contributions to PC telecommunications." In 1993, he received the Pioneer Award from the Electronic Frontier Foundation.

Christensen worked at IBM from 1968 until his retirement in 2012. His last position with IBM was field technical sales specialist.

In May 2005, Christensen and Suess were both featured in BBS: The Documentary.

🔗 Books 🔗 Psychology

The Origin of Consciousness in the Breakdown of the Bicameral Mind is the 1976 book by the Princeton psychologist, psychohistorian and consciousness theorist Julian Jaynes (1920-1997). The book addresses the problematic nature of consciousness – “the ability to introspect” – which in Jaynes’s view must be distinguished from sensory awareness and other processes of cognition. Jaynes presents his proposed solution: that consciousness is a “learned behavior” based more on language and culture than on biology; this solution, in turn, points to the origin of consciousness in ancient human history rather than in metaphysical or evolutionary processes; furthermore, archaeological and historical evidence indicates that prior to the “learning” of consciousness, human mentality was what Jaynes called "the bicameral mind" – a mentality based on verbal hallucination.

The first edition was released in January 1977 in English. Two later editions, in 1982 and in 1990, were released by Jaynes with additions but without alterations. It was Jaynes's only book, and it is still in print, in several languages. In addition to numerous reviews and commentaries, there are several summaries of the book's material, for example, in the journal Behavioral and Brain Sciences, in lectures and discussions published in Canadian Psychology, and in Art/World.

🔗 Internet 🔗 Computing 🔗 Brands 🔗 Microsoft 🔗 Home Living

The iLoo (short for Internet loo) was a cancelled Microsoft project to develop a Wi-Fi Internet-enabled portable toilet. The iLoo, which was to debut at British summer festivals, was described as being a portable toilet with wireless broadband Internet, an adjustable plasma screen, a membrane wireless keyboard, a six-channel speaker system, and toilet paper embossed with popular web site addresses. The iLoo was also to have an extra screen and keyboard on the outside, and was to be guarded. It was intended as the next in a series of successful initiatives by MSN UK which sought to introduce the internet in unusual locations, including MSN Street, MSN Park Bench and MSN Deckchair.

The project was announced by MSN UK on April 30, 2003, and was widely ridiculed before being declared a hoax by Microsoft on May 12. On May 13, another Microsoft press release stated that although the project had not been a hoax, it had been cancelled because it would do little to promote the MSN brand. There has since been speculation as to whether the project was cancelled for fear of being sued by Andrew Cubitt, who had invented the similarly named product "i-Loo". The iLoo was described as a public relations "debacle" by Online Journalism Review.