This thesis focuses on organized crime that has recently become one of the most serious global problems threatening the stability, security and development of civil society. At the beginning of the thesis, its author defines a basic term ,,organized crime" and its relation to the organized criminality. Then the author deals with the history of organized crime groups, describes the most important of the groups, and concentrates on new forms of organized crime. Furthermore, the author lists Czech and international substantive and procedural legal regulations with regard to the organized crime. Finally, the author discusses other non-legal means of the fight against the organized crime. The main part of the thesis is devoted to the methodology of investigation with a focus on specific initiatives and the subject of investigation, initial and subsequent acts, and the specific versions of investigation, planning, organization of investigation, and prevention. In greater detail, the thesis deals with methods of witnesses hearing, and especially with the legal concept of a secret witness, and protection provided to witnesses by special law, and the concept of a cooperating accused person. The thesis also analyzes operative and investigative means and other means of investigation.

Doctor of Philosophy / Department of Electrical and Computer Engineering / Balasubramaniam Natarajan / Widely recognized security vulnerabilities in current wireless radio access technologies undermine the benefits of ubiquitous mobile connectivity. Security strategies typically rely on bit-level cryptographic techniques and associated protocols at various levels of the data processing stack. These solutions have drawbacks that have slowed down the progress of new wireless services. Physical layer security approaches derived from an information theoretic framework have been recently proposed with secret key generation being the primary focus of this dissertation. Previous studies of physical layer secret key generation (PHY-SKG) indicate that a low secret key generation rate (SKGR) is the primary limitation of this approach. To overcome this drawback, we propose novel SKG schemes to increase the SKGR as well as improve the security strength of generated secret keys by exploiting multiple input and multiple output (MIMO), cooperative MIMO (co-op MIMO) networks. Both theoretical and numerical results indicate that relay-based co-op MIMO schemes, traditionally used to enhance LTE-A network throughput and coverage, can also increase SKGR. Based on the proposed SKG schemes, we introduce innovative power allocation strategies to further enhance SKGR. Results indicate that the proposed power allocation scheme can offer 15% to 30% increase in SKGR relative to MIMO/co-op MIMO networks with equal power allocation at low-power region, thereby improving network security. Although co-op MIMO architecture can offer significant improvements in both performance and security, the concept of joint transmission and reception with relay nodes introduce new vulnerabilities. For example, even if the transmitted information is secured, it is difficult but essential to monitor the behavior of relay nodes. Selfish or malicious intentions of relay nodes may manifest as non-cooperation. Therefore, we propose relay node reliability evaluation schemes to measure and monitor the misbehavior of relay nodes. Using a power-sensing based reliability evaluation scheme, we attempt to detect selfish nodes thereby measuring the level of non-cooperation. An overall node reliability evaluation, which can be used as a guide for mobile users interested in collaboration with relay nodes, is performed at the basestation. For malicious behavior, we propose a network tomography technique to arrive at node reliability metrics. We estimate the delay distribution of each internal link within a co-op MIMO framework and use this estimate as an indicator of reliability. The effectiveness of the proposed node reliability evaluations are demonstrated via both theoretical analysis and simulations results. The proposed PHY-SKG strategies used in conjunction with node reliability evaluation schemes represent a novel cross-layer approach to enhance security of cooperative networks.

University of Macau / Faculty of Arts and Humanities. / Department of English

A dissertação aborda a proteção da privacidade nas comunicações eletrônicas reservadas no Brasil. Objetiva apresentar a situação atual dessa questão no país e fazer uma análise crítica comparativa. Conceitua privacidade, comunicações, reservadas e dados pessoais como requisitos para a compreensão do assunto. Analisa o direito dos Estados Unidos da América, da União Européia e do Conselho da Europa, os Projetos de Lei em trâmite no Senado Federal e na Câmara dos Deputados e a situação brasileira atual. A metodologia de pesquisa consiste na consulta e interpretação de fontes jurídicas nacionais, internacionais e de direito estrangeiro, como os tratados, leis e jurisprudência atinentes à questão da privacidade nas comunicações eletrônicas, a partir da qual se desenvolve uma construção argumentativa, dedutiva e indutiva para uma crítica construtiva. Conclui que a mencionada proteção é desequilibrada e inadequada e propõe alterações interpretativas e legislativas. / The paper approaches the protection of the reserved electronic communications privacy in Brazil. Its goal is to present the current situation of this matter in the country and to develop a critical comparative analysis. It conceptualizes privacy, communications, reserved and personal data as requirements to understand the subject. It analyses the law of the United States of America, of the European Union and of the Council of Europe, the bills in the Federal Senate and in the House of Representatives and the current Brazilian legislation. Its methodology consists of examination and interpretation of national, international and foreign sources of law, such as treaties, statutes and case-law related to the electronic communications privacy question, which forms a basis from which it develops an argumentative, deductive and inductive reasoning for a constructive criticism. It concludes that the mentioned protection is imbalanced and inadequate and proposes legislative and interpretative changes.

Este estudo parte de uma visão teórica da literatura policial para analisar obras de três escritores latino-americanos: Machado de Assis, Jorge Luis Borges e Roberto Bolaño. O objetivo é fornecer um novo subsídio teórico para a leitura destes autores e, por outro lado, aprofundar a visão sobre o gênero policial no Brasil, ampliando, a partir dele, as discussões relacionadas à teoria literária. A causa secreta é um conto contemporâneo ao marco do nascimento do gênero policial nos Estados Unidos, com Edgar Allan Poe. Neste momento em que a literatura policial ainda não está consolidada, Machado de Assis cria também um personagem apaixonado pela análise dos caracteres humanos, o médico Garcia. Desde o título, como nos livros policiais, o leitor está procurando um segredo, cuja solução depende de sua confiança na autoridade narrativa, mas, em última análise, nunca pode ser realmente liquidado, porque nele reside o enigma fundamental da literatura: a impossibilidade de apropriação do Outro. Em El jardín de senderos que se bifurcan, Jorge Luis Borges usa o gênero para travar uma discussão sobre o tempo na narrativa e revolve o relato sobre si mesmo, usando uma autoinserção temporal. Foi considerado, assim, uma subversão na medida em que, pretensamente, destrói as balizas de gênero. Entretanto, segundo Jacques Derrida, um gênero é formado não só de marcas que identificam uma obra com a outra, mas também por alterações dentro da forma, que aumentam os limites genéricos. Desta forma, Borges, do ponto de vista da literatura policial, ajuda a criar um novo subgênero, o policial metafísico. Desde a perspectiva de um novo policial que discute seu próprio estatuto, analisamos o romance do escritor chileno Roberto Bolaño, Los detectives salvajes, em que lemos a história da busca de uma pessoa que, na verdade, está morta e só sabemos de sua morte no final da narrativa. Isso opera uma diferença fundamental: esta obra narra pela lente do luto, enquanto no policial esta dimensão é suplantada pela necessidade da intriga. De outra forma, o percurso dos personagens também responde à sombra do enigma que é a voz do Outro. A literatura policial, assim, é um gênero caracterizado por uma busca incessante, motivada por um enigma que o detetive precisa solucionar. Tradicionalmente, esta demanda é bem sucedida. Entretanto, nunca vemos o personagem, satisfeito por mais um trabalho resolvido, voltar para casa, o que prova que, de alguma forma, nem ele mesmo está convencido da solução do enigma. O segredo, portanto, exige uma dedicação infinita. De alguma forma, o personagem modelar do detetive reflete o trabalho do crítico literário. A busca incessante, o solilóquio que esconde o enigma, a necessidade de autoridade narrativa são questões importantes do nosso trabalho. Qual seria a responsabilidade, portanto, do crítico? Estaria disposto a sacrificar sua autoridade pela verdade? / This research begins with a theoretical vision of crime fiction to analyze works of three Latin-american authors: Machado de Assis, Jorge Luis Borges and Roberto Bolaño. The objective is to offer a new theoretical basis for reading these writers and also to deepen the study of crime fiction in Brazil, widening, thus, the debates regarding literary theory. A causa secreta is a short story contemporary of the birth of crime fiction in the United States, with Edgar Allan Poe. In that moment, when crime fiction wasnt consolidated yet, Machado de Assis also created a character passionate for the analysis of human character, doctor Garcia. From the title, as to the mystery book itself, the reader is looking for a secret, and the solution will only be brought through the readers distrust of the narrative settings. But the enigma, in fact, can never be solved because within it there is the fundamental secret of literature: the impossibility of appropriation of the Other. In El jardín de senderos que se bifurcan Jorge Luis Borges uses the genre to discuss time in fiction and turns the narrative upon itself by creating a temporal auto insertion. It is considered, thus, a subversion as it allegedly destroys the laws of the genre. However, according to Jacques Derrida, a genre is formed not only by the marks that defines it, but also by the alterations within its form, which enlarges its limits. In this way, through the point of view of crime fiction, Borges contributes to create a new subgenre: the metaphysical crime fiction. Through the perspective of a new crime fiction that questions its own statute, we analyzed the novel Los detectives salvajes, by Chilean author Roberto Bolaño, in which we read the story of a search of a person who, actually, is already dead, and we only get to know it in the end of the novel. This operates a structural difference: the book narrates through the lens of mourning, while in crime fiction this sentiment is superseded by the necessity of intrigue. In another way, the course of those characters also responds to the shadows of the enigma that is the voice of the Other. Crime fiction, thus, is a genre based on a relentless quest, motivated by an enigma that the detective has to solve. Traditionally, this demand is well succeeded. But we never see the detective, satisfied after another job well done, going back home, which proves that, in a way, not even he is convinced that the enigma is solved. In a way, the model character of the detective reflects, as some authors suggest, the work of the literary critic. The endless search, the monologue that hides the enigma, the necessity of narrative authority all this elements are important to our work. Then, what is the responsibility of the critic? Is he willing to sacrifice his authority for the truth?

Little interest has been shown in the leadership of voluntary providers of informal education for young people. This is true of one of the largest providers: the Scout Association. The thesis examines the nature, diversity and sources of the knowledge and understanding of leadership of Scout Association leaders in one English Midlands city. The understanding is compared with contemporary ways of understanding leadership in education using a typology established by Gunter and Ribbins (2003) and Gunter (2005). The impact of leader training on the understanding of leadership and its perceived effect on leader performance is explored. A case study methodology is used including a questionnaire method supported by documentary evidence and drawing on personal experience. Data analysis involves factor analysis, analysis of variance and Chi-square tests. Findings indicate that leadership is understood in terms of inclusion and success and has an ethical basis pointing to a belief in shared leadership. Variations in this understanding exist amongst different groups. Understanding of leadership mainly comes from sources within the Association. There is a degree of uncertainty amongst leaders about the impact of leader training. Leadership is interpreted in a range of ways as described by the Gunter and Ribbins (2003) and Gunter (2005) typology. The findings could have implications for how the Association develops an understanding of leadership in the future and could influence the thinking and decision making of all leaders in the Association, in particular training managers and trainers from local to national levels of the organisation. The findings may also have implications for researchers interested in the impact of market forces on leadership in the formal education sector.

Esta tese investiga os papéis políticos assumidos pela produção e o uso de estatísticas sobre crimes e criminosos na história recente das instituições que compõem o chamado sistema de justiça criminal brasileiro (polícias Civil e Militar, Ministério Público, Poder Judiciário e Estabelecimentos Carcerários), em São Paulo. Por meio da análise de documentos e formulários de coleta de dados, defende-se que, mesmo após a redemocratização e as pressões para a estruturação de procedimentos de controle público das agências estatais de pacificação social, o segredo permanece como modus-operandi desse sistema, no qual dados são produzidos, mas não há coordenação entre produtores e usuários; entre oferta e demanda da informação. Dessa forma, não havendo consenso sobre os papéis das estatísticas criminais disponíveis, há um movimento simultâneo de crescimento dos estoques de dados gerados como subproduto da adoção de modernas ferramentas de informática, de um lado, e, paradoxalmente, há o reforço da opacidade e da “experiência" institucional das práticas burocráticas no desenho e operação de políticas públicas de pacifi cação social, de outro. O resultado alcançado reforça a manutenção dos mecanismos de reprodução de verdades profissionais e institucionais nos modelos vigentes de segurança pública e justiça criminal, garantindo a permanência e a governabilidade em relação às pressões democráticas por mudanças nos padrões de policiamento e no acesso à justiça. / This thesis investigates the political roles taken by the production and use of crime and criminal offenders statistics on the recent history of the institutions that compose the Brasilian criminal justice system (the police, prosecution, judiciary and prisons) in São Paulo. Through the analysis of documents and data collecting forms, the thesis defends that, despite the redemocratization and the (political) pressure in order to organize the public control procedures of the governmental agencies of social pacifi cation, the secret remains the modus operandi of this system, in which data is produced but there is no coordination between producers and users or supply and demand of information. Along with the lack of consensus on the roles of the available criminal statistics, there is, on the one hand, an increment of data stores resulting from the constant use of technological tools. On the other hand, the opaqueness and institucional “experience" of bureaucratic practices are reinforced in planing and managing public policies of social pacifi cation. The consequence is the maintenance of mechanisms that reproduce institutional and professional truths in the current models of public law enforcement and criminal justice and that guarantee the permanence and governmentability in relation to democratic pressure for changes in the patterns of policing and access to justice.

O tema do segredo jornalístico ecoa profundamente no campo do processo penal, com grandes discussões não apenas teóricas, mas de atual importância prática para o futuro do direito à informação e para uma necessidade de realização da justiça. É nesse ponto de intersecção ampla liberdade de imprensa e acertamento de uma verdade processual justa que se acirra o debate sobre ser absoluto ou relativo o sigilo da fonte, com apresentação de inúmeras razões favoráveis ou contrárias a essa espécie particular de segredo. O consenso doutrinário e jurisprudencial acerca da questão está longe de ser atingido, sobretudo porque o status jurídico constitucional do sigilo jornalístico parece protegê-lo de intervenções limitativas do legislador, sempre vistas, politicamente, como espécies de agressão. Este trabalho, portanto, dedica-se a examinar a confidencialidade da fonte de informação jornalística como limite à prova penal no contexto da sociedade contemporânea da comunicação midiática. A tese que ora propomos é que o sigilo da fonte de informação jornalística, regra de direito e garantia fundamental prevista no art. 5º XIV da Constituição Federal brasileira, é um limite à prova no processo penal. Do ponto de vista do direito à informação, o sigilo é instrumento destinado ao jornalista para o exercício de sua profissão e que também está a serviço da própria democracia. Com a tutela constitucional do anonimato da identidade da fonte, o profissional do meio de comunicação pode ser mais bem informado para informar a sociedade. Essa sociedade, por sua vez, através do conhecimento sobre a atuação dos Poderes do Estado, que a mídia lhes proporciona, tem a possibilidade de poder participar, efetivamente, do regime democrático. Do ponto de vista do processo penal, a busca da verdade processual é o caminho da realização da justiça no qual a prova é imprescindível para que Estado encontre solidez na legitimação de seu poder de punir, e o indivíduo acusado de crime, por sua vez, possa realizar o seu direito à liberdade. Quando surge o processo como garantia de liberdade do indivíduo e necessário para o ius puniendi estatal, nasce ínsito a ele um direito à prova dos fatos, que deve ser exercido na sua maior amplitude, mas dentro de limites legais e de dignidade humana, tudo como corolário de um justo e devido processo legal. A presente investigação analisa a conexão, a relação desses institutos distintos: se, e como será possível compatibilizar a garantia constitucional do sigilo da fonte e a garantia do acusado em obter provas para sua defesa, quando a testemunha for um profissional da comunicação e quando documentos necessários à comprovação dos fatos estiverem em poder do jornalista ou da redação do jornal. Evidencia-se, então, a dificuldade de conciliar valores tão relevantes num Estado Democrático de Direito. O sigilo do jornalista como limite à prova não encontra amparo no art. 207 do CPP, como os demais segredos profissionais, pois o profissional da mídia tem a função de publicar fatos, não mantê-los sob reserva, que é exigência da mencionada norma. Portanto, o tratamento jurídico que deve ser dispensado ao sigilo jornalístico, em relação à prova penal, não se assemelha ao empregado para análise dos demais segredos. No intuito de proteger a origem da informação e tão somente essa é tutelada - se necessário e a critério do profissional, o procedimento probatório exigirá das partes e do juiz algumas especificidades, sob pena de a prova colhida ser considerada ilícita, se produzida com ofensa à regra constitucional mencionada. Além do mais, com o progresso tecnológico dos meios de comunicação amplia-se o problema das questões relacionadas às fontes de prova. Assim, as informações confidenciais vazadas do Departamento de Estado dos Estados Unidos da América, publicadas pelo WikiLeaks, com o impacto que teve na opinião pública mundial e nas relações com diversos países, as notícias anônimas divulgadas em redes sociais como blogs, facebook, twiter, workut, vão gerar discussões sobre a necessidade, ou não, de estabelecimento de limites à prova, sobretudo de defesa de acusados de práticas de crimes. Concluímos que é possível assegurar um efetivo direito à prova das partes no processo penal, respeitando o limite constitucional da confidencialidade da fonte de informação jornalística. Ambos são valores tutelados pela Constituição de 1988 os quais, no entanto, se colidirem, encontram na regra mencionada a opção do legislador constituinte pelo sigilo da fonte, quando necessário ao exercício profissional. / Le thème du secret journalistique retentit profondément dans le domaine de la procédure pénale, suscitant de grandes discussions non seulement théoriques mais aussi d\'importance actuelle pratique pour l\'avenir du droit à l\'information et pour une nécessité de réalisation de justice. C\'est à ce point de convergence, entre l\'ample liberté de presse et l\'assurance d\'une vérité de procédure équitable, que s\'enflamme le débat sur les thèses absolutistes et relativistes du secret de la source où l\'on présente d\'innombrables raisons favorables ou contraires à cette variété particulière de secret. Le consensus doctrinaire et jurisprudentiel autour de la question est loin d\'être atteint surtout parce que le statut juridique constitutionnel du secret journalistique semble le protéger d\'interventions limitatives du législateur, toujours perçues politiquement comme des genres d\'agression. Ce travail a, donc, pour but d\'examiner la confidentialité de la source d\'information journalistique comme limite à la preuve pénale dans le contexte de la société contemporaine de communication médiatique. La thèse que nous proposons à présent est que le secret de la source d\'information journalistique règle de droit et garantie fondamentale prévue par l\'article 5ème XIV de la Constitution de la République fédérative du Brésil est une limite à la preuve dans la procédure pénale. Du point de vue du droit à l\'information, le secret est un outil destiné au journaliste pour l\'exercice de sa profession qui est aussi au service de la démocratie elle-même. Avec la protection constitutionnelle de l\'anonymat de l\'identité de la source, le professionnel du milieu de la communication peut être mieux informé pour informer la société. Avec la connaissance de l\'action des pouvoirs publics que les médias lui offrent, cette société a, à son tour, la possibilité de pouvoir participer effectivement du régime démocratique. Du point de vue de la procédure pénale, la quête de vérité de procédure est la voie d\'accomplissement de la justice, où la preuve est incontournable pour que l\'État retrouve de la solidité dans la légitimation de son pouvoir de punir et pour que l\'individu accusé de crime puisse, à son tour, exercer son droit à la liberté. Lorsque la procédure sourd comme gage de liberté de l\'individu et est nécessaire pour l\'ius puniendi de l\'État, il en provient un droit inné à la preuve des faits qui doit être exercé dans sa plus grande ampleur gardant, cependant, les limites légales et de dignité humaine, le tout comme corollaire d\'une procédure légale due et équitable. Cette recherche analyse la connexion, la relation de ces institutions distinctes : si et comment il sera possible de rendre compatibles l\'assurance constitutionnelle du secret de la source et l\'assurance pour l\'accusé de l\'obtention de preuves pour sa défense lorsque le témoin est un professionnel de la communication et lorsque les documents nécessaires à la preuve à l\'appui se trouvent en possession du journaliste ou de la rédaction du journal. Il appert, donc, la difficulté de concilier des valeurs si pertinentes dans un État de Droit et de Démocratie. Le secret du journaliste comme limite à la preuve ne trouve pas d\'appui dans l\'article 207 du CPP brésilien, comme les autres secrets professionnels, puisque le professionnel des médias a la fonction de publier les faits et non pas de les garder, ce qui est une exigence de la norme mentionnée. Par conséquent, le traitement juridique qui doit être accordé au secret journalistique en ce qui concerne la preuve pénale ne se ressemble pas à celui employé pour l\'analyse des autres secrets. Dans le but de protéger la source de l\'information elle seule protégée, si nécessaire, selon l\'appréciation du professionnel la procédure probatoire exigera des parties et du juge quelques spécificités, sous peine d\'avoir la preuve amassée considérée illicite si elle est produite offensant la règle constitutionnelle mentionnée. En outre, avec le progrès technologique des moyens de communication, le problème des questions liées aux sources des preuves s\'élargit. Ainsi, les fuites d\'informations confidentielles du Département d\'État des États-Unis d\'Amérique publiées par WikiLeaks et son impact sur l\'opinion publique mondiale et dans les relations avec plusieurs pays, les nouvelles anonymes divulguées dans les réseaux sociaux tels que blogs, facebook, twiter, workut, vont générer des discussions sur la nécessité ou le manque de nécessité d\'établir des limites à la preuve, surtout dans la défense des accusés de pratiques criminelles. Nous arrivons à la conclusion qu\'il est possible d\'assurer un droit effectif à la preuve des parties de la procédure pénale en respectant la limite constitutionnelle du secret de la source d\'information journalistique. Toutes les deux sont des valeurs protégées par la Constitution de 1988. En se heurtant, elles ont toutefois trouvé, dans la règle citée, l\'option du législateur constituant pour le secret de la source, \"lorsque nécessaire à l\'exercice de la profession\".

Radio Frequency Identification (RFID) technology has been expanded to be used in different fields that need automatic identifying and verifying of tagged objects without human intervention. RFID technology offers a great advantage in comparison with barcodes by providing accurate information, ease of use and reducing of labour cost. These advantages have been utilised by using passive RFID tags. Although RFID technology can enhance the efficiency of different RFID applications systems, researchers have reported issues regarding the use of RFID technology. These issues are making the technology vulnerable to many threats in terms of security and privacy. Different RFID solutions, based on different cryptography primitives, have been developed. Most of these protocols focus on the use of passive RFID tags. However, due to the computation feasibility in passive RFID tags, these tags might be vulnerable to some of the security and privacy threats. , e.g. unauthorised reader can read the information inside tags, illegitimate tags or cloned tags can be accessed by a reader. Moreover, most consideration of reserchers is focus on single tag authentication and mostly do not consider scenarios that need multi-tag such as supply chain management and healthcare management. Secret sharing schemes have been also proposed to overcome the key management problem in supply chain management. However, secret sharing schemes have some scalability limitations when applied with high numbers of RFID tags. This work is mainly focused on solving the problem of the security and privacy in multi-tag RFID based system. In this work firstly, we studied different RFID protocols such as symmetric key authentication protocols, authentication protocols based on elliptic curve cryptography, secret sharing schemes and multi-tag authentication protocols. Secondly, we consider the significant research into the mutual authentication of passive RFID tags. Therefore, a mutual authentication scheme that is based on zero-knowledge proof have been proposed . The main object of this work is to develop an ECC- RFID based system that enables multi-RFID tags to be authenticated with one reader by using different versions of ECC public key encryption schemes. The protocol are relied on using threshold cryptosystems that operate ECC to generate secret keys then distribute and stored secret keys among multi RFID tags. Finally, we provide performance measurement for the implementation of the proposed protocols.

Le projet de recherche se propose d’explorer le rapport particulier entre « l’écrire » et la magie en se plaçant au plus près de la matérialité de l’écriture : avec quoi et sur quoi écrit-on ? Les romans antiques et les aventures du roi Arthur et des chevaliers de la Table Ronde, des XIIème et XIIIème siècles, œuvres qui constituent notre corpus*, font état de parchemins, de « lettres », de tissus ou vêtements, de peaux d’animaux ou humaine, de supports végétaux, de pierres tombales, d’armes sur lesquels on écrit, parfois avec deux ou trois couleurs, avec différents « instruments » : plumes d’oiseau (avec des encres), stylets pointus par exemple. De manière atypique, des substrats éphémères comme la farine, la cendre, la neige apparaissent ; le sang des hommes (ou des animaux), souvent, y laisse des traces, des signes. Les messages ainsi écrits ne sont pas toujours fondés sur l’alphabet (par exemple dans le Lai du Chèvrefeuille). Le support et la forme de ces écritures ont un sens particulier et confèrent une valeur magique aux messages laissés, par les personnages, hommes ou femmes, magiciens ou initiés. L’imaginaire de l’écrire est différent de celui de l’écriture: il repose sur le support, sa matérialité et sera la piste à privilégier dans notre enquête. Nous nous poserons donc la question de l’intentionnalité des signes dans ces messages, en fonction du choix du support, quel qu’il soit. Les œuvres de notre corpus ont été écrites dans une période qui connaît l’immense développement, en langue vernaculaire, de la littérature médiévale ; elle a un lien très fort avec l’oralité et le folklore. Notre enquête accordera une importance particulière aux traditions populaires, au folklore, aux croyances magiques ; les contes, les légendes, les textes hagiographiques ainsi que des textes à valeurs non littéraires seront considérés pour comprendre la part de l’imaginaire dans l’acte d’écrire, en prenant en compte, le cas échéant, des récits d’autres aires culturelles, extra-européennes et en réfléchissant sur la dimension anthropologique de l’acte d’écrire. De même, les noms (des personnes, des lieux) ainsi que les dates seront considérés avec attention. Le concept d’«écriture magique » sera défini et cerné : qu’envisageons-nous dans cette magie qui peut être liée aux supports, aux signes, à la langue utilisée pour rédiger le message, et à la personne qui écrit ? Il s’agira donc de donner un sens au mot « magie » en se fondant sur l’étymologie, sa relation au sacré, à la religion, à la sorcellerie. Nous nous appuierons dans cette recherche sur ce qui est connu des supports cités dans le corpus, en nous fondant sur le relevé des occurrences des termes décrivant l’acte d’écrire, et leur étymologie. Cette magie a une incidence sur l’imaginaire qui n’est pas un simple état de fait. Les œuvres de notre corpus gardent des traces de mythes anciens sur l’apparition de l’écriture (sans la confondre avec le dessin ou la peinture), de ses pouvoirs, de sa relation à la magie et au sacré. Ces mythes évoluent, coexistent avec la vision chrétienne mais ne meurent pas. Ils seront ainsi parties prenantes de notre recherche pour questionner les différents imaginaires de la cryptographie. * Corpus : - Les romans antiques o Le roman d’Eneas o Le roman de Thèbes o Le roman de Troie o Le roman d’Alexandre - La matière arthurienne o Chrétien de Troyes (Bibliothèque de la Pléiade) o Les poèmes tristaniens français, Le lai du Chèvrefeuille (et des références possibles à d’autres lais de Marie de France) o Continuations de Perceval o Le livre du Graal (Bibliothèque de la Pléiade) ; Le Livre du Graal I : Joseph d'Arimathie ; Merlin ; Les premiers faits du roi Arthur, ; Le Livre du Graal. II, Lancelot : de "La Marche de Gaule" à "La première partie de la quête de Lancelot", ; Le Livre du Graal. III Lancelot : la seconde partie de la quête de Lancelot. La Quête du saint Graal. La Mort du roi Arthur / The research project suggests exploring the particular relationship between " to write " and the magic by taking place as closely as possible to the materiality of the writing: with what and on what do we write? The antique novels and the adventures of king Arthur and Knights of the Round Table, XIIth and XIIIth centuries, works which constitute our corpus, state parchments, "letters", tissues or clothes, of skins of animals or human, plant supports, gravestones, weapons on which we write, sometimes with two or three colors, with various "instruments": feathers of bird (with ink), sharp stylets for example. In a atypical way, substrata short-lived as the flour, the ash, the snow appear; the blood of people (or animals), often, leaves with it signs. Messages written are not still established on the alphabet (for example in the Lay of the Honeysuckle). The support(medium) and the shape of these writings have a particular sense and confer a magic value on the left messages, by the characters, the menor the women, the magicians or the initiated people. The imagination of this kind of cryptography is different from that of the writing: it bases on the support, its materiality and will be the track to favor in our survey(investigation). We shall thus ask ourselves the question of the intentionality of the signs in these messages, according to the choice of the support(medium), whatever it is. The works of our corpus were written for a period which knows the immense development, in vernacular language, the medieval literature; it has a very strong link with the oral character and the folklore. Our survey(investigation) will grant(tune) a particular importance for the popular traditions, for the folklore, for the magic faiths; the tales, the legends, the hagiographic texts as well as the texts with not literary values will be considered to include the part of the imagination in the act to write, by taking into account, where necessary, narratives of the other cultural, extra-European areas and by thinking about the anthropological dimension of the act to write. Also, names (people, places) as well as dates will be considered with attention. The concept of " magic writing " will be defined and encircled: what do we envisage in this magic which can be bound(connected) to supports(media), to signs, to language(tongue) used to draft the message, and to the person who writes? Il will thus involve of giving a sense(direction) to the word "magic" by basing(establishing) itself on the etymology, its relation in the sacred, in the religion, in the witchcraft. We shall lean in this search(research) on what is known supports(media) quoted in the corpus, by basing(establishing) us on the statement of the cases(occurrences) of the terms describing the act to write, and their etymology. This magic has an incidence on the imagination which is not a simple established fact. The works of our corpus keep(guard) tracks of former(old) myths on the appearance of the writing (without her(it) confusing(merging) with the drawing or the paint(painting)), of its powers, his(her,its) relation for the magic and for the sacred. These myths evolve, coexist with the Christian vision but do not die. They will so be stakeholders of our search(research) to question the various imagination of cryptography