Cryptology: A didactical transposition into grade 10 school Mathematics classroom

Philosophiae Doctor - PhDThis study in an extension of a Master's study, entitled Realistic Mathematics Education and the strategies grade 8 learners develop for the solution of two simultaneous linear equations. the current study investigates how new content could be introduced into a school mathematical curriculum. The new topic under discussion for this study is the topis of Cryptology. Two research cycles were carried out. For the first design research cycle there were three teaching experiments with teachers, grade 10 learners and students as participants. Seven activities weere developed from the second design research cycle which was worked through with gade 10 learners. All sessions for the second design research cycle were video taped. Important to the development of instrutional materials was the development of a hypothetical learning trajetory about the learning and teaching of each activity. the results of the study indicated that the way learners understood the content and the different ways in which they presented solutions augers well for the introduction of a specific new content strand, cryptology, into a new school mathematical curriculum. It is also important for developers of instructional material to have a strong mathematical content knowledge for the design of instructional materialsSouth Afric

The Cryptographic Imagination

Originally published in 1996. In The Cryptographic Imagination, Shawn Rosenheim uses the writings of Edgar Allan Poe to pose a set of questions pertaining to literary genre, cultural modernity, and technology. Rosenheim argues that Poe's cryptographic writing—his essays on cryptography and the short stories that grew out of them—requires that we rethink the relation of poststructural criticism to Poe's texts and, more generally, reconsider the relation of literature to communication. Cryptography serves not only as a template for the language, character, and themes of much of Poe's late fiction (including his creation, the detective story) but also as a "secret history" of literary modernity itself. "Both postwar fiction and literary criticism," the author writes, "are deeply indebted to the rise of cryptography in World War II." Still more surprising, in Rosenheim's view, Poe is not merely a source for such literary instances of cryptography as the codes in Conan Doyle's "The Dancing-Men" or in Jules Verne, but, through his effect on real cryptographers, Poe's writing influenced the outcome of World War II and the development of the Cold War. However unlikely such ideas sound, The Cryptographic Imagination offers compelling evidence that Poe's cryptographic writing clarifies one important avenue by which the twentieth century called itself into being. "The strength of Rosenheim's work extends to a revisionistic understanding of the entirety of literary history (as a repression of cryptography) and then, in a breathtaking shift of register, interlinks Poe's exercises in cryptography with the hyperreality of the CIA, the Cold War, and the Internet. What enables this extensive range of applications is the stipulated tension Rosenheim discerns in the relationship between the forms of the literary imagination and the condition of its mode of production. Cryptography, in this account, names the technology of literary production—the diacritical relationship between decoding and encoding—that the literary imagination dissimulates as hieroglyphics—the hermeneutic relationship between a sign and its content."—Donald E. Pease, Dartmouth Colleg

A Study in Authenticity : Admissible Concealed Indicators of Authority and Other Features of Forgeries : A Case Study on Clement of Alexandria, Letter to Theodore, and the Longer Gospel of Mark

A standard approach in historically minded disciplines to documents and other artefacts that have become suspect is to concentrate on their dissimilarities with known genuine artefacts. While such an approach works reasonably well with relatively poor forgeries, more skilfully done counterfeits have tended to divide expert opinions, demanding protracted scholarly attention. As there has not been a widespread scholarly consensus on a constrained set of criteria for detecting forgeries, a pragmatic maximum for such dissimilarities—as there are potentially an infinite numbers of differences that can be enumerated between any two artefacts—has been impossible to set. Thus, rather than relying on a philosophically robust critical framework, scholars have been accustomed to approaching the matter on a largely case-by-case basis, with a handful of loosely formulated rules for guidance. In response to these shortcomings, this dissertation argues that a key characteristic of inquiry in historically minded disciplines should be the ability to distinguish between knowledge-claims that are epistemically warranted—i.e., that can be asserted post hoc from the material reality they have become embedded in with reference to some sort of rigorous methodological framework—and knowledge-claims that are not. An ancient letter by Clement of Alexandria (ca. 150–215 CE) to Theodore, in which two passages from the Longer Gospel of Mark (also known as the Secret Gospel of Mark) are quoted, has long been suspected of having been forged by Morton Smith (1915–1991), its putative discoverer. The bulk of this dissertation consists of four different articles that each use different methodological approaches. The first, a discourse analysis on scholarly debate over the letter’s authenticity, illuminates the reasons behind its odd character and troubled history. Second, archival research unearths how data points have become corrupted through unintended additions in digital-image processing (a phenomenon labelled line screen distortion here). Third, a quantitative study of the handwriting in Clement’s Letter to Theodore shows the inadequacy of unwittingly applying palaeographic standards in cases of suspected deceptions compared to the standards adhered to in forensic studies. Additionally, Smith’s conduct as an academic manuscript hunter is found to have been consistent with the standard practices of that profession. Finally, a study of the conceptual distinctions and framing of historical explanations in contemporary forgery discourse reveals the power of the methodologic approach of WWFD (What Would a Forger Do?), which has recently been used in three varieties (unconcealed, concealed, and hyperactive) to construe suspected documents as potential forgeries—despite its disregard of justificatory grounding in favour of coming up with free-form, first-person narratives in which the conceivable functions as its own justification. Together, the four articles illustrate the pitfalls of scholarly discourse on forgeries, especially that surrounding Clement’s Letter to Theodore. The solution to the poor argumentation that has characterized the scholarly study of forgeries is suggested to be an exercise in demarcation: to decide (in the abstract) which features should be acceptable as evidence either for or against the ascription of the status of forgery to an historical artefact. Implied within this suggestion is the notion of constraint, i.e., such that a constrained criterion would be one that cannot be employed to back up both an argument and its counter-argument. A topical case study—a first step on the road to creating a rigorous standard for constrained criteria in determining counterfeits—is the alternative narrative of an imagined creation of Clement’s Letter to Theodore by Smith around the time of its reported discovery (1958). Concealed indicators of authority, or the deliberate concealment of authorial details within the forged artefact by the forger, is established as a staple of the literary strategy of mystification, and their post hoc construction as acceptable evidence of authorship is argued to follow according to criteria: 1) that the beginning of the act of decipherment of a concealed indicator of authority has to have been preceded by a literary primer that is unambiguous to a high degree, 2) that, following the prompting of the literary primer, the act of deciphering a concealed indicator of authority has to have adhered to a technique or method that is unambiguous to a high degree, and 3) that, following the prompting of the literary primer and the act of decipherment, both of which must have been practiced in an unambiguous manner to a high degree, the plain-text solution to the concealed indicator of authority must likewise be unambiguous to a high degree.Tässä väitöskirjassa tarkastellaan Klemens Aleksandrialaisen (n. 150-215 jaa.) kirjettä Theodorokselle, joka sisältää Salaisen Markuksen evankeliumin nimellä tunnettuja tekstikatkelmia. Näissä katkelmissa, jotka eivät sisälly kanonisoituun Uuteen testamenttiin, Jeesus mm. herättää nuorukaisen kuolleista ja opettaa tälle Jumalan valtakunnan salaisuuden. Klemensin kirje todistaa laajemmin kristinuskon varhaisvaiheen moninaisuudesta, mutta sitä on myös epäilty väärennökseksi. Historiallisten väärennösten tunnistamiseen ei ole löytynyt yleisesti hyväksyttyä metodia. Historiantutkijat ovat joutuneet arvioimaan epäiltyjä väärennöksiä tapauskohtaisesti, ja taidokkaasti toteutetut väärennökset johtavatkin usein pitkään ja kiivaaseen keskusteluun. Väitöskirjan ytimen muodostavat neljä artikkelia, joissa tarkastellaan Klemensin kirjettä eri näkökulmista ja kuvataan myös yleisemmin historiallisten väärennösten paljastamiseen liittyviä sudenkuoppia. Ensimmäinen artikkeli kuvaa diskurssianalyysin keinoin väärennösväitteistä käytyä sananvaihtoa, jota leimaa puhuminen toisten tutkijoiden ohi ja yli. Toinen ja kolmas artikkeli analysoivat Klemensin kirjeen käsialaa. Ne paljastavat, että digitaalinen kuvankäsittely on tahattomasti muokannut käsialan yksityiskohtia. Vertailuaineisto osoittaa, ettei Klemensin kirjeen käsiala sisällä "väärentäjän vapinaa" tai muita yleisiä väärennöksen tuntomerkkejä. Neljäs artikkeli tarkastelee ja problematisoi tutkijoiden tapaa perustella väärennösväitteitä luomalla kuvitteellisia tarinoita, joilla selitetään väärennöksien yksityiskohtien syntymistä. Väitöskirjassa ehdotetaan, että historiallisten väärennösten paljastamiseen täytyy kehittää vankka tieteellinen viitekehys. Väitöskirjan yhteenvetoluvussa otetaan tähän ensimmäinen askel tarkastelemalla, kuinka autenttisuuden kysymystä on lähestytty mm. kirjallisuustieteen alalla. Yhteenvetoluvussa analysoidaan mystifikaatiolle (kirjallinen genre) tyypillistä tapaa piilottaa "kätkettyjä tekijyyden indikaattoreita" väärennöksiin. Analyysin perusteella todetaan, että aiemmin tutkijat ovat saattaneet langeta kehittelemään villejä väärennösteorioita erilaisten kuviteltujen vihjeiden ja salakirjoitusten pohjalta. Jotta vältytään tämänkaltaiselta "kryptoanalyyttiseltä hyperaktiivisuudelta," tarvitaan "kätkettyjen tekijyyden indikaattoreiden" käytölle kriteerejä. Ehdotettujen kriteerien mukaan ainoastaan sellaiset "kätketyt tekijyyden indikaattorit" voidaan hyväksyä todellisiksi, joiden 1) olemassaoloon viitataan yksiselitteisesti, joiden 2) purkaminen tapahtuu yksiselitteisellä metodilla ja jotka 3) nimeävät tekijän yksiselitteisellä tavalla

The history and sociology of computer science and technology, collected vol. 4

A historiography and source material

Furtive Encryption: Power, Trusts, and the Constitutional Cost of Collective Surveillance

Recent revelations of heretofore secret U.S. government surveillance programs have sparked national conversations about their constitutionality and the delicate balance between security and civil liberties in a constitutional democracy. Among the revealed policies asserted by the National Security Agency (NSA) is a provision found in the “minimization procedures” required under section 702 of the Foreign Intelligence Surveillance Act of 1978. This provision allows the NSA to collect and keep indefinitely any encrypted information collected from domestic communications—including the communications of U.S. citizens. That is, according to the U.S. government, the mere fact that a U.S. citizen has encrypted her electronic communications is enough to give the NSA the right to store that data until it is able to decrypt or decode it. Through this provision, the NSA is automatically treating all electronic communications from U.S. citizens that are hidden or obscured through encryption—for whatever reason—as suspicious, a direct descendant of the “nothing-to-hide” family of privacy minimization arguments. The ubiquity of electronic communication in the United States and elsewhere has led to the widespread use of encryption, the vast majority of it for innocuous purposes. This Article argues that the mere encryption by individuals of their electronic communications is not alone a basis for individualized suspicion. Moreover, this Article asserts that the NSA’s policy amounts to a suspicionless search and seizure. This program is therefore in direct conflict with the fundamental principles underlying the Fourth Amendment, specifically the protection of individuals from unwarranted government power and the establishment of the reciprocal trust between citizen and government that is necessary for a healthy democracy

Analyse et Conception d'Algorithmes de Chiffrement Légers

The work presented in this thesis has been completed as part of the FUI Paclido project, whose aim is to provide new security protocols and algorithms for the Internet of Things, and more specifically wireless sensor networks. As a result, this thesis investigates so-called lightweight authenticated encryption algorithms, which are designed to fit into the limited resources of constrained environments. The first main contribution focuses on the design of a lightweight cipher called Lilliput-AE, which is based on the extended generalized Feistel network (EGFN) structure and was submitted to the Lightweight Cryptography (LWC) standardization project initiated by NIST (National Institute of Standards and Technology). Another part of the work concerns theoretical attacks against existing solutions, including some candidates of the nist lwc standardization process. Therefore, some specific analyses of the Skinny and Spook algorithms are presented, along with a more general study of boomerang attacks against ciphers following a Feistel construction.Les travaux présentés dans cette thèse s’inscrivent dans le cadre du projet FUI Paclido, qui a pour but de définir de nouveaux protocoles et algorithmes de sécurité pour l’Internet des Objets, et plus particulièrement les réseaux de capteurs sans fil. Cette thèse s’intéresse donc aux algorithmes de chiffrements authentifiés dits à bas coût ou également, légers, pouvant être implémentés sur des systèmes très limités en ressources. Une première partie des contributions porte sur la conception de l’algorithme léger Lilliput-AE, basé sur un schéma de Feistel généralisé étendu (EGFN) et soumis au projet de standardisation international Lightweight Cryptography (LWC) organisé par le NIST (National Institute of Standards and Technology). Une autre partie des travaux se concentre sur des attaques théoriques menées contre des solutions déjà existantes, notamment un certain nombre de candidats à la compétition LWC du NIST. Elle présente donc des analyses spécifiques des algorithmes Skinny et Spook ainsi qu’une étude plus générale des attaques de type boomerang contre les schémas de Feistel

Computer and data security: a comprehensive annotated bibliography.

Massachusetts Institute of Technology, Alfred P. Sloan School of Management. Thesis. 1973. M.S.MICROFICHE COPY ALSO AVAILABLE IN DEWEY LIBRARY.M.S

Genre games: Edward Gorey's play with generic form

This thesis examines Edward Gorey's play with form and content across five literary genres, how that play results in the style that has come to be known as the "Goreyesque" and how the Goreyesque has influenced later artists and writers. Gorey consistently places style ahead of thematic and moral considerations, removing the purpose of each genre to reveal what remains in its absence. In doing so, Gorey maps out the boundaries of each form, providing genre- and period-specific details that act as signposts to how his audience should approach each narrative. With these markers in place, Gorey's readers are thus made aware of which genre expectations rule each piece. These expectations, however, are undermined as Gorey removes the audience-understood literary endgame, so that the work appears in all respects to be an accurate representation of the chosen genre, yet is missing the central heart. Gorey's melodramas present scenarios in which deep familial loss and suffering are at the forefront of each narrative, yet as a result of the distance that Gorey places between the text and his readers, these works ultimately lack sentimentality. His Dickensian narratives, while populated with virtuous orphans and embittered, isolated men, lack moral pronouncements and just rewards, resulting in exceptionally bleak, nihilistic endings that provide little or no social commentary. His children's literature, although full of mnemonic systems, rejects all pedagogical functions in favour of inviting in adult audiences to luxuriate in sound and linguistic form. His mystery and detective fiction, while containing secrets, crimes and criminals, ignores any pretence of decoding the central mysteries. His Gothic horror revels in supernatural excesses, yet engenders no fear. By tracing Gorey's play with genre, we can identify the aesthetic parameters of the Goreyesque, and examine how they manifest in the works of other artists and writers, notably Tim Burton, Neil Gaiman and Roman Dirge. In manipulating genre expectations, Gorey does more than simply leave readers with the shell of narrative purpose. Instead, he draws attention to the absence and pushes beyond expectation to reinvention. He normalizes the strange and fantastic by removing the very things that make the ordinary extraordinary. He infuses his works with a distance that shifts their purpose from generating high emotion and strong reactions to encouraging minute attention to narrative detail. Gorey's fantasies therefore represent odd, underwhelming moments that are otherwise ignored in the search for the uncommon and unique. By underplaying the significance of the events in his stories, Gorey represents and refreshes our concepts of the fantastic, and highlights the strangeness in the overlooked