Posts Tagged ‘communications’
“Engineering is the art of modeling materials we do not wholly understand, into shapes we cannot precisely analyze, so as to withstand forces we cannot properly assess, in such a way that the public has no reason to suspect”*…
… and so, for a very long time, it has been. Consider the case of the inventive Ismail al-Jazarī, a predecessor of Da Vinci…
… Al-Jazarī, who passed away in 1206, served as the chief engineer for the court of the Artuqids in Diyarbakir. His Book of Knowledge of Ingenious Mechanical Devices lives up to its name, detailing lock-like devices for raising water, sophisticated zodiac clocks, avian automata able to produce song, and a showering system for King Salih, who “disliked a servant or slave girl pouring water onto his hands for him”. He invented bloodletting technologies, mischievous fountains, segmental gears, and a chest (sundūq) that featured a security system with four combination dials — presumably a safe for storing valued possessions — and has been subsequently dubbed “the father of robotics”, due to his creation of a life-like butler who could offer guests a hand towel after their ablutions. Al-Jazarī’s contemporaries already recognized his eminence as an engineer, referring to him as unique and unrivaled, learned and worthy. He stood on the shoulders of Persian, Greek, Indian, and Chinese precursors, while Renaissance inventors, in turn, stood on his.
The Book of Knowledge of Ingenious Mechanical Devices contains some fifty mechanical devices divided into six categories: clocks; vessels and figures for drinking sessions; pitchers, basins, and other washing devices; fountains and perpetual flutes; machines for raising water; and a miscellaneous category, where we find a self-closing door. The second category is perhaps the most intriguing, and grants some insight into the extravagant concerns of al-Jazarī’s courtly patrons. One machine — “a standing slave holding a fish and a goblet from which he serves wine to the king” — is programmed to dispense clarified wine every eighth of an hour for a certain period. Numerous similar devices follow: robots that drink from goblets, which are filled from the recycled contents of their stomachs; automaton shaykhs that serve each other wine that each consumes in turn; a boat full of mechanical slave girls that play instruments during drinking parties. Not unlike our “AI assistants”, al-Jazarī’s inventions are never allowed to transcend the category of indentured laborer, reproducing the inequalities of social relations across the human-machine divide.
The illustrations from the Berlin manuscript are notably different than some of its sister specimens, such as the ornate pair of manuscripts held in Leiden. Here the images are mainly in-line illustrations and seem more focused on technical details and inner workings than other versions, which tend to lean toward aesthetic exteriors. Red and yellow predominate, offset by the occasional body of water in indigo blue. Gears and levers are rich in tone, while humanoid figures get left as simple, colorless sketches. To the contemporary viewer, the illustrations invert the power dynamic that is so present in al-Jazarī’s text. Machines come to the foreground; humans are incidental figures, almost irrelevant…
Putting material to work. More– and many more illustrations: “Ismail al-Jazarī’s Ingenious Mechanical Devices,” from @PublicDomainRev.
More of (and on) al-Jazarī’s creations here.
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As we imagine machines, we might spare a thought for Henry Christopher Mance; he died on this date in 1926. An electrical engineer and inventor, he was instrumental in laying the earliest underwater telecom cables (under the Persian Gulf) and developed the Mance method of detecting and locating the positions of defects in submarine cables. But he is better remembered as the inventor of the Mance heliograph (a wireless solar telegraph that signals by flashes of sunlight using Morse code reflected by a mirror), which found wide military, survey, and forest protection application and for which he was knighted.
“There are two types of encryption: one that will prevent your sister from reading your diary and one that will prevent your government”*…
… But sometimes the encryption you think will work against governments won’t even deter your sister. Joesph Cox on the recently-uncovered vulnerabilities in TETRA, the encryption standard used in radios worldwide…
A group of cybersecurity researchers has uncovered what they believe is an intentional backdoor in encrypted radios used by police, military, and critical infrastructure entities around the world. The backdoor may have existed for decades, potentially exposing a wealth of sensitive information transmitted across them, according to the researchers… The end result, however, are radios with traffic that can be decrypted using consumer hardware like an ordinary laptop in under a minute…
The research is the first public and in-depth analysis of the TErrestrial Trunked RAdio (TETRA) standard in the more than 20 years the standard has existed. Not all users of TETRA-powered radios use the specific encryption algorithim called TEA1 which is impacted by the backdoor. TEA1 is part of the TETRA standard approved for export to other countries. But the researchers also found other, multiple vulnerabilities across TETRA that could allow historical decryption of communications and deanonymization. TETRA-radio users in general include national police forces and emergency services in Europe; military organizations in Africa; and train operators in North America and critical infrastructure providers elsewhere.
Midnight Blue [presented] their findings at the Black Hat cybersecurity conference in August. The details of the talk have been closely under wraps, with the Black Hat website simply describing the briefing as a “Redacted Telecom Talk.” That reason for secrecy was in large part due to the unusually long disclosure process. Wetzels told Motherboard the team has been disclosing these vulnerabilities to impacted parties so they can be fixed for more than a year and a half. That included an initial meeting with Dutch police in January 2022, a meeting with the intelligence community later that month, and then the main bulk of providing information and mitigations being distributed to stakeholders. NLnet Foundation, an organization which funds “those with ideas to fix the internet,” financed the research.
The European Telecommunications Standards Institute (ETSI), an organization that standardizes technologies across the industry, first created TETRA in 1995. Since then, TETRA has been used in products, including radios, sold by Motorola, Airbus, and more. Crucially, TETRA is not open-source. Instead, it relies on what the researchers describe in their presentation slides as “secret, proprietary cryptography,” meaning it is typically difficult for outside experts to verify how secure the standard really is.
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Bart Jacobs, a professor of security, privacy and identity, who did not work on the research itself but says he was briefed on it, said he hopes “this really is the end of closed, proprietary crypto, not based on open, publicly scrutinised standards.”…
The veil, pierced: “Researchers Find ‘Backdoor’ in Encrypted Police and Military Radios,” from @josephfcox in @motherboard. (Not long after this article ran– and after the downfall of Vice, Motherboard’s parent), Cox and a number of his talented Motherboard colleagues launched 404 Media. Check it out.)
Remarkably, some of the radio systems enabling critical infrastructure are even easier to hack– they aren’t even encrypted.
* Bruce Schneier (@schneierblog)
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As we take precautions, we might recall that it was on this date in 1980 that the last IBM 7030 “Stretch” mainframe in active use is decommissioned at Brigham Young University. The first Stretch was was delivered to Los Alamos National Laboratory in 1961, giving the model almost 20 years of operational service.
The Stretch was famous for many things, but perhaps most notably it was the first IBM computer to use transistors instead of vacuum tubes; it was the first computer to be designed with the help of an earlier computer; and it was the world’s fastest computer from 1961 to 1964.
“Whoever wishes to keep a secret must hide the fact that he possesses one”*…
… or, as Sheon Han explains, maybe not…
Imagine you had some useful knowledge — maybe a secret recipe, or the key to a cipher. Could you prove to a friend that you had that knowledge, without revealing anything about it? Computer scientists proved over 30 years ago that you could, if you used what’s called a zero-knowledge proof.
For a simple way to understand this idea, let’s suppose you want to show your friend that you know how to get through a maze, without divulging any details about the path. You could simply traverse the maze within a time limit, while your friend was forbidden from watching. (The time limit is necessary because given enough time, anyone can eventually find their way out through trial and error.) Your friend would know you could do it, but they wouldn’t know how.
Zero-knowledge proofs are helpful to cryptographers, who work with secret information, but also to researchers of computational complexity, which deals with classifying the difficulty of different problems. “A lot of modern cryptography relies on complexity assumptions — on the assumption that certain problems are hard to solve, so there has always been some connections between the two worlds,” said Claude Crépeau, a computer scientist at McGill University. “But [these] proofs have created a whole world of connection.”…
More about how zero-knowledge proofs allow researchers conclusively to demonstrate their knowledge without divulging the knowledge itself: “How Do You Prove a Secret?,” from @sheonhan in @QuantaMagazine.
* Johann Wolfgang von Goethe
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As we stay sub rosa, we might recall that today (All Saints Day) is the (fictional) birthday of Hello Kitty (full name: Kitty White); she was born in a suburb of London. A cartoon character designed by Yuko Shimizu (currently designed by Yuko Yamaguchi), she is the property of the Japanese company Sanrio. An avatar of kawaii (cute) culture, Hello Kitty is one of the highest-grossing media franchises of all time; Hello Kitty product sales and media licensing fees have run as high as $8 billion a year.
“One of the most singular characteristics of the art of deciphering is the strong conviction possessed by every person, even moderately acquainted with it, that he is able to construct a cipher which nobody else can decipher.”*…
And yet, for centuries no one has succeeded. Now, as Erica Klarreich reports, cryptographers want to know which of five possible worlds we inhabit, which will reveal whether truly secure cryptography is even possible…
Many computer scientists focus on overcoming hard computational problems. But there’s one area of computer science in which hardness is an asset: cryptography, where you want hard obstacles between your adversaries and your secrets.
Unfortunately, we don’t know whether secure cryptography truly exists. Over millennia, people have created ciphers that seemed unbreakable right until they were broken. Today, our internet transactions and state secrets are guarded by encryption methods that seem secure but could conceivably fail at any moment.
To create a truly secure (and permanent) encryption method, we need a computational problem that’s hard enough to create a provably insurmountable barrier for adversaries. We know of many computational problems that seem hard, but maybe we just haven’t been clever enough to solve them. Or maybe some of them are hard, but their hardness isn’t of a kind that lends itself to secure encryption. Fundamentally, cryptographers wonder: Is there enough hardness in the universe to make cryptography possible?
In 1995, Russell Impagliazzo of the University of California, San Diego broke down the question of hardness into a set of sub-questions that computer scientists could tackle one piece at a time. To summarize the state of knowledge in this area, he described five possible worlds — fancifully named Algorithmica, Heuristica, Pessiland, Minicrypt and Cryptomania — with ascending levels of hardness and cryptographic possibility. Any of these could be the world we live in…
Explore each of them– and their implications for secure encryption– at “Which Computational Universe Do We Live In?” from @EricaKlarreich in @QuantaMagazine.
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As we contemplate codes, we might we might send communicative birthday greetings to a frequently–featured hero of your correspondent, Claude Elwood Shannon; he was born on this date in 1916. A mathematician, electrical engineer– and cryptographer– he is known as “the father of information theory.” But he is also remembered for his contributions to digital circuit design theory and for his cryptanalysis work during World War II, both as a codebreaker and as a designer of secure communications systems.
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