Tesis sobre el tema "Réseau de Poste"
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Buyukkaya, Eliya. "Une architecture pair-à-pair pour les environnements virtuels en réseau". Paris 6, 2011. http://www.theses.fr/2011PA066124.
Texto completoKhiat, Nassima. "Détection et mitigation de vers dans le coeur de réseau : application aux réseaux Pair-à-Pair". Thesis, Evry-Val d'Essonne, 2010. http://www.theses.fr/2009EVRY0033.
Texto completoThe Internet and its users are daily the object of attacks of malware. Among them, we can find the worms, which distinguish themselves from the other attacks by their automatic way of propagation. This makes them potentially very dangerous. To make their propagation easier and faster, the worms can attack popular applications. The generalization of the use of Peer-to-Peer networks makes them a perfect target of worms called "Peer-to-Peer worms". These worms, and in particular the passive ones, are characterized by their stealthy. Indeed, they generate no suspect traffic, and are so difficult to detect in the network. The purpose of this thesis is to propose an effective solution against the passive Peer-to-Peer worms, to make Peer-to-Peer networks, which begin to be used to distribute some legal contents such as the VoD (Video on Demand) ones, more secure. We propose several algorithms and an architecture to detect the passive Peer-to-Peer worms in the network. We evaluate our algorithms in a simulator which we have developed, as well as with an analytical study. We then study the mitigation issue of the detected worms
Weiss, Stéphane. "Edition collaborative massive sur réseaux Pair-à-Pair". Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00542853.
Texto completoVeglia, Paolo. "Applications TV pair-à-pair conscientes du réseau". Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00647980.
Texto completoLouati, Wassef. "Un système de nommage pair-à-pair pour la découverte et la mise en réseau de services dans les environnements dynamiques étendus". Evry, Institut national des télécommunications, 2007. http://www.theses.fr/2007TELE0019.
Texto completoBonnel, Nicolas Achille Jacques. "Adapnet : stratégies adaptatives pour la gestion de données distribuées sur un réseau pair-a pair". Lorient, 2008. http://www.theses.fr/2008LORIS134.
Texto completoIn the last few years, the amount of digital information produced has exponentially increased. This raises problems regarding the storage, the access and the availability of this data. Software and hardware architectures based on the peer-to-peer (p2p) paradigm seem to satisfy the needs of data storage but cannot handle efficiently both data accessibility and availability. We present ,in this thesis various contributions on p2p architectures for managing large volumes of information. We propose various strategies that operate on dedicated virtual topologies that can be maintained at low cost. More precisely, these topologies scale well because the cost for node arrival and node departure is on average constant, whatever the size of the network. We analyze the main paradigms of information sharing on a p2p network, considering successively the problem of access to typed information (semi-structured) and the general case that completely separates the nature of the queries and data location. We propose a routing strategy using structure and content of semi-structured information. We also propose strategies that efficiently explore the network when there is no assumption on the nature of data or queries. In order to manage a quality of service (which is expressed ln terms of speed and reliability), we, also investigate the problem of information availability, more precisely we replicate data stored ln the network. We propose a novel approach exploiting an estimation of local density of data
Blin, Eric. "La localisation des services publics : L'aménagement du réseau postal de Seine-Maritime". Rouen, 1993. http://www.theses.fr/1992ROUEL163.
Texto completoAs a legacy from the past, the postal network is not well adapted. The few creations and suppressions which have been made are quite insufficient in so far as urbanization and changes in social behaviour are concerned. Moreover, the post office don't have any rigorous and overall methods to reorganize its network at a regional level. Thus weakness perfectly suits the politicians who rule creations and suppressions. A location-allocation model, as the p-median problem, turns out to be an excellent means to solve the dilemma "efficiency-equity" which is typical of public facilities. This model has been adapted to the Seine-Maritime network, trying to get as close as possoble to reality. Its particularity is to face development at the level of a region combining both urban areas, while remaining simple, as population and distance are the only mainsprings. Thanks to simulations, it has been possible to define the guidelines of such a development. Even though the post office should gradually shrink, creations and suppressions must eventually lead to the constitution of a strong framework. Nevertheless, a model only remains e tool for development, leaving the post office and local authorities the ability to readjust the network proposed, and proceed to secondary developments. That should be convincing enough to get that model adopted
Moualla, Ghada. "Virtualisation résiliente des fonctions réseau pour les centres de données et les environnements décentralisés". Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4061.
Texto completoTraditional networks are based on an ever-growing variety of network functions that run on proprietary hardware devices called middleboxes. Designing these vendor-specific appliances and deploying them is very complex, costly and time-consuming. Moreover, with the ever-increasing and heterogeneous short-term services requirements, service providers have to scale up their physical infrastructure periodically, which results in high CAPEX and OPEX. This traditional paradigm leads to network ossification and high complexity in network management and services provisioning to address emerging use cases. Network Function Virtualization (NFV) has attracted notable attention as a promising paradigm to tackle such challenges by decoupling network functions from the underlying proprietary hardware and implementing them as software, named Virtual Network Functions (VNFs), able to work on inexpensive commodity hardware. These VNFs can be arranged and chained together in a predefined order, the so-called Service Function chaining (SFC), to provide end-to-end services. Despite all the benefits associated with the new paradigm, NFV comes with the challenge of how to place the functions of the users' requested services within the physical network while providing the same resiliency as if a dedicated infrastructure were used, given that commodity hardware is less reliable than the dedicated one. This problem becomes particularly challenging when service requests have to be fulfilled as soon as they arise (i.e., in an online manner). In light of these new challenges, we propose new solutions to tackle the problem of online SFC placement while ensuring the robustness of the placed services against physical failures in data-center (DC) topologies. Although recovery solutions exist, they still require time in which the impacted services will be unavailable while taking smart placement decisions can help in avoiding the need for reacting against simple network failures. First, we provide a comprehensive study on how the placement choices can affect the overall robustness of the placed services. Based on this study we propose a deterministic solution applicable when the service provider has full knowledge and control on the infrastructure. Thereafter, we move from this deterministic solution to a stochastic approach for the case where SFCs are requested by tenants oblivious to the physical DC network, where users only have to provide the SFC they want to place and the required availability level (e.g., 5 nines). We simulated several solutions and the evaluation results show the effectiveness of our algorithms and the feasibility of our propositions in very large scale data center topologies, which make it possible to use them in a productive environment. All these solutions work well in trusted environments with a central authority that controls the infrastructure. However, in some cases, many enterprises need to collaborate together in order to run tenants' application, e.g., MapReduce applications. In such a scenario, we move to a completely untrusted decentralized environment with no trust guarantees in the presence of not only byzantine nodes but also rational nodes. We considered the case of MapReduce applications in such an environment and present an adapted MapReduce framework called MARS, which is able to work correctly in such a context without the need of any trusted third party. Our simulations show that MARS grants the execution integrity in MapReduce linearly with the number of byzantine nodes in the system
Simatos, Florian. "Etudes de modèles probabilistes de réseaux par-à-pair et de réseaux avec mobilité". Palaiseau, Ecole polytechnique, 2009. http://pastel.paristech.org/5681/01/thesis.pdf.
Texto completoHenri, Camille. "La Poste et les transports : la messagerie et l’apprentissage de la concurrence (1969-2003)". Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1061.
Texto completoOn the late 60s till the early 21st century, this thesis describes the issue of La Poste shipment, a focus on the dynamic large technical system and the historical network architecture starting inside the firm. This analysis reveals the considerable change inside La Poste across the years: the evolution of the shipment, the expertise and especially the way how they improve their business because of their competitors. All this lead them to develop their business in the messaging field and to restructure the way of packaging inside La Poste Group. This study reveals that their business has grown considerably over the years and that shipment research has contributed to give them the knowledge inside the company. One of the assumptions of this thesis considers that the historical approach has lead the group to improve their way of shipment and to develop a change strategy : it's the reorganisation inside the group, the internal restructuring of the shipment and messaging, and also the new definition of a relationship between this exceptional way of shipment and the whole world. The aim challenge of the operator is to be able to develop the business of the company trying to have a pole position on the market and insure a public service. This thesis also reveals that one of the major issues of la Poste by the past, was to develop their business and to be identified as one of the leader in this section. This fundamental change linked to the expansion of the shipment messaging, make us consider that the influence of the shipment experience and the competitors postal service had contributed to define the knowledge of the firm, we consider it as a major step for la Poste and allow us to get more curious on the competitor's learning since the late 1970s
Delahaye, Hélène. "Dissonances et convergences entre conduites du quotidien et productions de service : le cas du réseau des bureaux de poste". Phd thesis, Université Paris-Est, 2009. http://tel.archives-ouvertes.fr/tel-00584400.
Texto completoBergé, Nathalie. "Modélisation au moyen des réseaux de Petri temporisés stochastiques d'une application de contrôle-commande de poste de transformation d'énergie électrique répartie sur le réseau de terrain FIP". Phd thesis, Université Paul Sabatier - Toulouse III, 1996. http://tel.archives-ouvertes.fr/tel-00139777.
Texto completoBourgougnon, Nathalie. "Modélisation au moyen des Réseaux de Petri Temporisés Stochastiques d'une application de contrôle-commande de poste de transformation d'énergie électrique répartie sur le réseau de terrain FIP". Toulouse 3, 1996. http://www.theses.fr/1996TOU30132.
Texto completoMadi, Ghadir. "Optimisation d'un réseau de capteurs par techniques MIMO coopératives". Poitiers, 2012. http://theses.univ-poitiers.fr/25302/2012-Madi-Ghadir-These.pdf.
Texto completoWireless sensor networks (WSN) have a wide range of applications in various fields and consist of a large number of low-cost, low-power distributed sensors. Energy efficiency of sensors is the most critical issue in the system design of the network. The aim of this thesis is to study the application of recent MIMO techniques in the context of cooperative MIMO forWSN in order to reduce energy consumption. These techniques are based on the max−dmin and P-OSM precoders which require the knowledge of the channel state information (CSI) at transmitter. To make the use of the CSI realistic in WSN, we quantized these two precoders. The idea is to reduce the information sent on the feedback channel while still having a good performance of the precoders. We used some techniques from the literature and proposed others to perform this quantization. We then proposed various energy-efficient cooperative schemes that allow the implementation of max−dmin and P-OSM precoders with a quantized feedback channel. Performances of the proposed schemes in terms of energy consumption and transmission delay are evaluated and analyzed by comparing them with the space-time block codes (STBC) based cooperative scheme used in literature. Results show that our proposed systems provide more energy savings than the STBC one even in the presence of synchronization errors between the sensors. We are further interested in the application of sensor networks in high-voltage substations in the context of the Smart Grid. The objective is to evaluate the performance of proposed cooperative systems in the presence of impulsive noise and in a real environment of high-voltage substation in Quebec. By using measured data of impulsive noise obtained from the Ecole de Technologie Supérieure of Montreal, we determined a statistical model of the impulsive noise. In order to use the multi-antenna system, we propose an extension of this model
Bellachehab, Anass. "Pairwise gossip in CAT(k) metric spaces". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0017.
Texto completoThis thesis deals with the problem of consensus on networks. Networks under study consists of identical agents that can communicate with each other, have memory and computational capacity. The network has no central node. Each agent stores a value that, initially, is not known by other agents. The goal is to achieve consensus, i.e. all agents having the same value, in a fully distributed way. Hence, only neighboring agents can have direct communication. This problem has a long and fruitful history. If all values belong to some vector space, several protocols are known to solve this problem. A well-known solution is the pairwise gossip protocol that achieves consensus asymptotically. It is an iterative protocol that consists in choosing two adjacent nodes at each iteration and average them. The specificity of this Ph.D. thesis lies in the fact that the data stored by the agents does not necessarily belong to a vector space, but some metric space. For instance, each agent stores a direction (the metric space is the projective space) or position on a sphere (the metric space is a sphere) or even a position on a metric graph (the metric space is the underlying graph). Then the mentioned pairwise gossip protocols makes no sense since averaging implies additions and multiplications that are not available in metric spaces: what is the average of two directions, for instance? However, in metric spaces midpoints sometimes make sense and when they do, they can advantageously replace averages. In this work, we realized that, if one wants midpoints to converge, curvature matters. We focused on the case where the data space belongs to some special class of metric spaces called CAT(k) spaces. And we were able to show that, provided initial data is "close enough" is some precise meaning, midpoints-based gossip algorithm – that we refer to as Random Pairwise Midpoints - does converge to consensus asymptotically. Our generalization allows to treat new cases of data spaces such as positive definite matrices, the rotations group and metamorphic systems
Veron, Maxime Pierre Andre. "Scalable services for massively multiplayer online games". Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066212.
Texto completoMassively Multi-player Online Games (MMOGs) aim at gathering an infinite number of players within the same virtual universe. Yet all existing MMOGs rely on centralized client/server architectures which impose a limit on the maximum number of players (avatars) and resources that can coexist in any given virtual universe. This thesis aims at proposing solutions to improve the scalability of MMOGs. To address the wide variety of their concerns, MMOGs rely on independent services such as virtual world hosting, avatar storage, matchmaking, cheat detection, and game design. This thesis explores two services that are crucial to all MMOG variants: matchmaking and cheat detection. Both services are known bottlenecks, and yet current implementations remain centralized. This thesis also shows that it is possible to design a peer to peer refereeing service on top of a reputation system. The resulting service remains highly efficient on a large scale, both in terms of performance and in terms of cheat prevention. Since refereeing is somewhat similar to failure detection, this thesis extends the proposed approach to monitor failures. The resulting failure detection service scales with the number of monitored nodes and tolerates jitter
Yeferny, Taoufik. "Proposition d'approches de routage de requêtes dans les systèmes pair-à-pair non structurés". Phd thesis, Institut National des Télécommunications, 2014. http://tel.archives-ouvertes.fr/tel-01048671.
Texto completoMoniak, Gérald. "Techniques MIMO pour un lien sans fil robuste entre un bus et un poste de contrôle pour une application de surveillance embarquée". Valenciennes, 2007. https://ged.uphf.fr/nuxeo/site/esupversions/916a3d61-2731-4b0c-9963-6e1e19557266.
Texto completoThis works deals with a wireless link between a bus and a control centre for embedded audio and video monitoring. Our work is split in three part: the MIMO channels and its modelling, the development of the transmission chain in simulation and its evaluation, the development of a real transmission chain. First, a state of the art of the modelling of the MIMO channel is presented. Real channels are measured and its modelling by the Kronecker and Weichselberger models are studied. The transmitter of the considered chained is based on the WiMAX standard. Two receivers are presented and evaluated: a simple receiver and a turbo receiver. Several channel models are used for the evaluation of the performance. The Turbo receiver proved more effective in terms of bits errors rate. It is more resistant to the spatial correlation and to the errors on the channel estimation. The correlation shows more prejudicial than line of sight for the system. Last, a real transmission module has been developed. The real chain corresponds to the RF part. The generation and the treatments of the signals are realized with developed software. First real transmissions show us a degradation of the performance in comparison with simulations. Alternatives solutions are proposed
Faria, Bernardes Daniel. "Information Diffusion in Complex Networks : Measurement-Based Analysis Applied to Modelling". Electronic Thesis or Diss., Paris 6, 2014. http://www.theses.fr/2014PA066066.
Texto completoUnderstanding information diffusion on complex networks is a key issue from a theoretical and applied perspective. Epidemiology-inspired SIR models have been proposed to model information diffusion. Recent papers have analyzed this question from a data-driven perspective. We complement these findings investigating if epidemic models calibrate with a systematic procedure are capable of reproducing key spreading cascade properties. We first identify a large-scale, rich dataset from which we can reconstruct the diffusion trail and the underlying network. Secondly, we examine the simple SIR model as a baseline model and conclude that it was unable to generate structurally realistic spreading cascades. We found the same result examining model extensions to which take into account heterogeneities observed in the data. In contrast, other models which take into account time patterns available in the data generate qualitatively more similar cascades. Although one key property was not reproduced in any model, this result highlights the importance of taking time patterns into account. We have also analyzed the impact of the underlying network structure on the models examined. In our data the observed cascades were constrained in time, so we could not rely on the theoretical results relating the asymptotic behavior of the epidemic and network topological features. Performing simulations we assessed the impact of these common topological properties in time-bounded epidemic and identified that the distribution of neighbors of seed nodes had the most impact among the investigated properties in our context. We conclude discussing identifying perspectives opened by this work
Bellachehab, Anass. "Pairwise gossip in CAT(k) metric spaces". Thesis, Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0017/document.
Texto completoThis thesis deals with the problem of consensus on networks. Networks under study consists of identical agents that can communicate with each other, have memory and computational capacity. The network has no central node. Each agent stores a value that, initially, is not known by other agents. The goal is to achieve consensus, i.e. all agents having the same value, in a fully distributed way. Hence, only neighboring agents can have direct communication. This problem has a long and fruitful history. If all values belong to some vector space, several protocols are known to solve this problem. A well-known solution is the pairwise gossip protocol that achieves consensus asymptotically. It is an iterative protocol that consists in choosing two adjacent nodes at each iteration and average them. The specificity of this Ph.D. thesis lies in the fact that the data stored by the agents does not necessarily belong to a vector space, but some metric space. For instance, each agent stores a direction (the metric space is the projective space) or position on a sphere (the metric space is a sphere) or even a position on a metric graph (the metric space is the underlying graph). Then the mentioned pairwise gossip protocols makes no sense since averaging implies additions and multiplications that are not available in metric spaces: what is the average of two directions, for instance? However, in metric spaces midpoints sometimes make sense and when they do, they can advantageously replace averages. In this work, we realized that, if one wants midpoints to converge, curvature matters. We focused on the case where the data space belongs to some special class of metric spaces called CAT(k) spaces. And we were able to show that, provided initial data is "close enough" is some precise meaning, midpoints-based gossip algorithm – that we refer to as Random Pairwise Midpoints - does converge to consensus asymptotically. Our generalization allows to treat new cases of data spaces such as positive definite matrices, the rotations group and metamorphic systems
Veron, Maxime Pierre Andre. "Scalable services for massively multiplayer online games". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066212/document.
Texto completoMassively Multi-player Online Games (MMOGs) aim at gathering an infinite number of players within the same virtual universe. Yet all existing MMOGs rely on centralized client/server architectures which impose a limit on the maximum number of players (avatars) and resources that can coexist in any given virtual universe. This thesis aims at proposing solutions to improve the scalability of MMOGs. To address the wide variety of their concerns, MMOGs rely on independent services such as virtual world hosting, avatar storage, matchmaking, cheat detection, and game design. This thesis explores two services that are crucial to all MMOG variants: matchmaking and cheat detection. Both services are known bottlenecks, and yet current implementations remain centralized. This thesis also shows that it is possible to design a peer to peer refereeing service on top of a reputation system. The resulting service remains highly efficient on a large scale, both in terms of performance and in terms of cheat prevention. Since refereeing is somewhat similar to failure detection, this thesis extends the proposed approach to monitor failures. The resulting failure detection service scales with the number of monitored nodes and tolerates jitter
Fayçal, Marguerite. "Routage Efficace pour les Réseaux Pair-à-Pair utilisant des Tables de Hachage Distribuées". Phd thesis, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00521935.
Texto completoFayçal, Marguerite. "Routage efficace pour les réseaux pair-à-pair utilisant des tables de hachage distribuées". Phd thesis, Paris, Télécom ParisTech, 2010. https://pastel.hal.science/pastel-00521935.
Texto completoThis dissertation is a synthesis of our research at Orange Labs (formerly France Telecom R&D) to answer a problem identified by the aforesaid network operator and concerning peer-to-peer (P2P) streams. The rise of P2P requires new systems to meet the needs of users, but also those of ISPs and other network operators. The former seek permanently quite noticeable high QoS; the latter aim to optimize the use of network resources and to reduce various operations’ and management costs. Hence the interest of this thesis, that aims to let a P2P network be aware of its underlying IP network in order to achieve a system with an efficient routing mechanism that leads to a win-win situation. Our research focuses on systems based on distributed hash tables (DHT), that we study and analyze first. This dissertation begins with an analysis of the main protocols for discovery of dynamic resources in the different P2P architectures. The requirements for efficient P2P routing are then established. Afterwards, discovery techniques for generating and providing underlay network proximity information are presented, followed by techniques and main systems that exploit such information. Our research led to the definition, design, specification and both individual and comparative analysis of two systems: CAP (Context-Aware P2P system) and NETPOPPS (Network Provider Oriented P2P System). The former introduces semantics in the identifiers of peers and objects and is context-aware. The latter simplifies the management of the different identifiers and is network operator oriented: it enables cooperation between P2P traffic and the underlay’s network operator (its policies and network topology)
Delpuech, Corinne. "Pourquoi et comment les grands groupes dépositaires d'une mission de service public s'approprient-ils les concepts de RSE et développement durable ? : application de la Poste et de GDF SUEZ". Thesis, Toulouse 1, 2012. http://www.theses.fr/2012TOU10008/document.
Texto completoThis research makes its contribution in the context of a decline in the traditional concept of “the public service” and, at the same time, the increasing importance of the notions of corporate social responsibility (CSR) and sustainable development (SD) in France. In the main we based our research on neo-institutional theory as applied to the study of two organizations : “La Poste” and “GDF Suez”. Our research shows that in these enterprises, both of which have a public service mission, the concept of CSR-SD is a rationalized myth of substitution, which becomes institutionalized allowing to find a cognitive and normative legitimacy in the internal as well as the external context, a legitimacy reduced and more and more disregarded during their shift from the public service model to the market economy model. The institutional contradictions between those models of public service andthe liberal market approach invite these corporate groups to look for an alternative institutional framework embodied in the particular case of CSR-SD. We used two complementary theoretical frameworks in our research. Actor Network theory showed how by spreading the idea of public interest, inherited from the public service, the issues of corporate social responsibility and sustainable development became a source of innovation in these companies. This innovation is evident when it emanates from an actors' network in which the State plays a significant role. We revealed mechanisms of organizational learning, mainly single-loop learning, during the process of embracing corporate social responsibility and sustainable development. This organizational learning is facilitated by the cognitive and cultural backgrounds of the actors, developed within the social framework of the public service, which strengthens the institutionalization of corporate social responsibility and sustainable development
Faria, Bernardes Daniel. "Information Diffusion in Complex Networks : Measurement-Based Analysis Applied to Modelling". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-01001763.
Texto completoTout, Rabih. "Sauvegarde des données dans les réseaux P2P". Phd thesis, Université Claude Bernard - Lyon I, 2010. http://tel.archives-ouvertes.fr/tel-00731829.
Texto completoRibeiro, Cardoso André. "Architecture basée sur les réseaux programmables et les réseaux pair-à-pair". Paris, ENST, 2007. http://www.theses.fr/2007ENST0038.
Texto completoToumlilt, Ilyas. "Colony : a Hybrid Consistency System for Highly-Available Collaborative Edge Computing". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS447.
Texto completoImmediate response, autonomy and availability is brought to edge applications, such as gaming, cooperative engineering, or in-the-field information sharing, by distributing and replicating data at the edge. However, application developers and users demand the highest possible consistency guarantees, and specific support for group collaboration. To address this challenge, COLONY guarantees Transactional Causal Plus Consistency (TCC+) globally, dovetailing with Snapshot Isolation within edge groups. To help with scalability, fault tolerance and security, its logical communication topology is tree-like, with replicated roots in the core cloud, but with the flexibility to migrate a node or a group. Despite this hybrid approach, applications enjoy the same semantics everywhere in the topology. Our experiments show that local caching and peer groups improve throughput and response time significantly, performance is not affected in offline mode, and that migration is seamless
Botero, Oscar. "Heterogeneous RFID framework design, analysis and evaluation". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2012. http://www.theses.fr/2012TELE0011.
Texto completoThe Internet of Things paradigm establishes interaction and communication with a huge amount of actors. The concept is not a new-from-scratch one; actually, it combines a vast number of technologies and protocols and surely adaptations of pre-existing elements to offer new services and applications. One of the key technologies of the Internet of Things is the Radio Frequency Identification just abbreviated RFID. This technology proposes a set of solutions that allow tracking and tracing persons, animals and practically any item wirelessly. Considering the Internet of Things concept, multiple technologies need to be linked in order to provide interactions that lead to the implementation of services and applications. The challenge is that these technologies are not necessarily compatible and designed to work with other technologies. Within this context, the main objective of this thesis is to design a heterogeneous framework that will permit the interaction of diverse devices such as RFID, sensors and actuators in order to provide new applications and services. For this purpose in this work, our first contribution is the design and analysis of an integration architecture for heterogeneous devices. In the second contribution, we propose an evaluation model for RFID topologies and an optimization tool that assists in the RFID network planning process. Finally, in our last contribution, we implemented a simplified version of the framework by using embedded hardware and performance metrics are provided as well as the detailed configuration of the test platform
Modrzejewski, Remigiusz. "Distribution et Stockage de Contenus dans les Réseaux". Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00917032.
Texto completoRahhal, Charbel. "Wikis sémantiques distribués sur réseaux pair-à-pair". Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00543961.
Texto completoSimonetta, Clio. "Le cheval de guerre au Japon, de son introduction au Xᵉsiècle". Electronic Thesis or Diss., Université Paris sciences et lettres, 2024. http://www.theses.fr/2024UPSLP028.
Texto completoThe purpose of this project is to study in detail the role of the horse in the military system ofancient Japan, from a logistical and tactical point of view. This animal, which is not native to the archipelago, was imported from Korea during the proto-historic period and subsequently became a central element of the art of war, as well as of the identity construction in warrior culture. While historical research has long focused on the evolution of mounted archers and of their social class, the horse itself and the complexity of its role in the military sphere has not received as much attention. Our subject concerns first of all the qualitative and biological aspects of the animal (its origin, its ethology, its physiology, etc.), and then analyzes the historical mechanisms having led to its diffusion through Asia, its adoption in the Japanese Islands, and the development of a military equestrian culture specific to Japan. The period examined covers the first adoption of horse rearing, up to the 10th century. We aim to place the diffusion of equestrian culture in its proper historical context and to study its possible links with the social, political and military evolution of the society as a whole.This research is based on a scientific approach, which highlights the data on the zoologicalhistory of the animal and its biological characteristics, in order to better interpret the archaeological and historical data. In our analysis, we will take into account the different uses of the military horse within the Department of Military Affairs of the Imperial Court: pack horse, postal network horse, warhorse. We will research the logistical consequences of these types of functions (supply, care, travel, etc.), as well as their effects on the economic, social and military context. For this, we relied mainly on available archaeological data, as well as a vast corpus of ancient sources, including annals, administrative texts, regulations issued by the Imperial Court, etc. The study of the warhorse will thus allow us a better understanding of the war phenomenon in Japan, which may shed light on several aspects of social conflicts and the use of power in Japan
Cabani, Adnane. "Réseaux pair-à-pair et simulation distribuée : application à la simulation multiagent". St Etienne du Rouvray, INSA, 2007. http://www.theses.fr/2007ISAM0025.
Texto completoRosas, Erika. "Services à base de communautés de confiance dans les réseaux P2P". Paris 6, 2011. http://www.theses.fr/2011PA066573.
Texto completoPolentes, Jérôme. "Plasticité post-lésionnelle des réseaux neurovégétatifs centraux : cas du réseau respiratoire. Récupération fonctionnelle après lésion médullaire et transplantation de cellules gliales gainantes olfactives". Aix-Marseille 3, 2005. http://www.theses.fr/2005AIX30026.
Texto completoThis doctoral work studied, after cervical hemisection in the adult rat, the incidence of a post-traumatic strategy of cell transplantation (Olfactory Ensheathing Cells; CGO) on post-lesional plasticity of a central neurovegetative network (the respiratory network) and on its functional recovery. Three to 6 months post-trauma (or post-lesion), a substantial functional recovery of the ipsilateral phrenic and diaphragmatic activity (mean 80% and 73% of the contralateral activity; Sham group: mean 29% and 10%) is obtained in the Transplanted animals. 57% of the phrenic activity in these animals persisted after suppression of any contralateral pathways. No similar ipsilateral activity could be evidenced in the Sham group. In addition, occurrence of Ipsilateral post-synaptic phrenic response to supralesional stimulations, among the Transplanted group only, reveals the presence of a phrenic reinnervation due to the transplantation strategy
Imine, Abdessamad. "Conception Formelle d'Algorithmes de Réplication Optimiste Vers l'Edition Collaborative dans les Réseaux Pair-à-Pair". Nancy 1, 2006. http://www.theses.fr/2006NAN10184.
Texto completoCollaborative editing systems provide computer support for manipulating objects such as a text document, shared by two or more users that are temporally and spatially distributed. Object replication is essential in such systems, but it can leads to a data divergence problem. To overcome this problem, an optimistic approach, called the operational transformation, is used. This thesis is aimed to propose a formal framework for designing correct transformation algorithms that can be embedded in collaborative editing systems for achieving data convergence. Firstly, we have proposed a formal methodology for specifying and verifying collaborative objects synchronized by operational transformation approach. This methodology relies on using advanced automated deduction techniques. Thanks to our formal framework, we have detected divergence situations in many well-known systems. Ensuring convergence for linear objects (such as a list, a text, an ordered XML tree) still remains challenging. In this respect, we have noticed that the known convergence conditions are hardly to be satisfied. So, we have proposed a new tranformation algorithm based on relaxed form of these conditions. Moreover, we have designed an integration environment for collaborative edition based on linear objects. The novelty of this environment is that it can be deployed in peer-to-peer networks (P2P). Lastly, we have proposed a compositional technique enabling construction of complex objects from primitive objects by preserving convergence criterias imposed on transformation algorithms
Ha, Duong Hoa Dung. "Partage de données en mode pair à pair sur réseaux mobiles ad hoc". Paris, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00573976.
Texto completoDesigning software for mobile ad hoc networks presents news challenges : in a manet, devices are mobile, resources are scarce and in absence of infrastructure, everything is decentralized. Therefore, a new algorithmic, adapted to manet, has to be defined. This thesis proposes a set of algorithms for developing a distributed data sharing system for manets: - a clustering algorithm to create groups of terminals stable over time. This algorithm's main advantage is that it does not create any network load since it uses cross-layering information from the routing layer to know which terminals are reachable. - a proactive replication algorithm, which, for each data, creates and maintains a number of replica proportional to the number of terminals, that it places on the devices where they are most likely to be used. This algorithm enhances data availability and data sharing reliability. - a cache management algorithm which tries to regulate the best number of replica so as to optimize the use of the network, while maintaining data availability. First of all, when a cache replacement is needed, the algorithm eliminates data less recently used, and for which the number of replica is high enough to maintain availability. It also reduces the network load by removing useless replica which generate network traffic (not used by their host)
Pianese, Fabio. "Systèmes pair à pair pour la diffusion de données vidéo : PULSE, un système adaptatif pour le streaming en direct sur Internet". Nice, 2007. http://www.theses.fr/2007NICE4058.
Texto completoLive Streaming consists in distributing live media (video and audio) to large audiences over a computer network. The traditional client-server approach to live streaming has a serious scalability limit, as the upload capacity requirement at the server grows linearly with the user population. A P2P solution has the big advantage of seamlessly scaling to arbitrary population sizes, as every node that receives the video, while consuming resources, can at the same time offer its own upload bandwidth to serve other nodes. In theory, if every node contributed on average at least as much as it consumed, the P2P system would have enough resources to grow indefinitely. This work presents and evaluates PULSE, a practical P2P live streaming system intended for large-scale deployment over the Internet. PULSE uses an unstructured mesh-based design and relies on local pairwise incentives as its peer selection mechanism. The most innovative feature of PULSE is the unique coupling of incentives with feedback derived from data reception, which leads to the emergence of clusters that regroup nodes with similar resources. By exploiting this intrinsic clustering phenomenon and by leveraging latency measurements to estimate network locality, PULSE is capable to successfully operate in a wide range of resource-constrained real world scenarios and to support dynamic user populations and heterogeneous node upload capacities
Vuillemin, Philippe. "Calcul itératif asynchrone sur infrastructure pair-à-pair : la plate-forme JaceP2P". Besançon, 2006. http://www.theses.fr/2006BESA2028.
Texto completoDesprat, Caroline. "Architecture événementielle pour les environnements virtuels collaboratifs sur le web : application à la manipulation et à la visualisation d'objets en 3D". Thesis, Toulouse 2, 2017. http://www.theses.fr/2017TOU20103/document.
Texto completoWeb technologies evolutions during last decades fostered the development of collaborative virtual environments for 3D design at large scale. Despite the fact that collaborative environments gather in a same shared space geographically distant users in a common objective, the hardware ressources of their clients (calcul, storage, graphics ...) are often underused because of the challenge it represents. It is indeed a matter of offering an easy-to-use, efficient and transparent collaborative system to the user supporting both computationnal and 3D design visualisation and business logic needs in heterogeneous web environments. To scale well, numerous systems use a network architecture called "hybrid", combining both client-server and peer-to-peer. Optimistic replication is well adapted to distributed application such as 3D collaborative envionments : the dynamicity of users and their numbers, the 3D data type used and the large amount and size of it.This document presents a model for 3D web-based collaborative editing systems. This model integrates 3DEvent, an client-based architecture allowing us to bring 3D business logic closer to the user using events. Indeed, the need of traceability and history awareness is required during 3D design especially when several experts are involved during the process. This aspect is intrinsec to event-sourcing design pattern. This architecture is completed by a peer-to-peer middleware responsible for the synchronisation and the consistency of the system. To implement it, we propose to use the recent web standard API called WebRTC, close to cloud development services know by developers. To evaluate the model, two user studies were conducted on several group of users concerning its responsiveness and the acceptance by users in the frame of cooperative assembly tasks of 3D models
Tomozei, Dan-Cristian. "Distributed algorithms for peer-to-peer networks". Paris 6, 2011. http://www.theses.fr/2011PA066059.
Texto completoPellet--Mary, Alice. "Réseaux idéaux et fonction multilinéaire GGH13". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN048/document.
Texto completoLattice-based cryptography is a promising area for constructing cryptographic primitives that are plausibly secure even in the presence of quantum computers. A fundamental problem related to lattices is the shortest vector problem (or SVP), which asks to find a shortest non-zero vector in a lattice. This problem is believed to be intractable, even quantumly. Structured lattices, for example ideal lattices or module lattices (the latter being a generalization of the former), are often used to improve the efficiency of lattice-based primitives. The security of most of the schemes based on structured lattices is related to SVP in module lattices, and a very small number of schemes can also be impacted by SVP in ideal lattices.In this thesis, we first focus on the problem of finding short vectors in ideal and module lattices.We propose an algorithm which, after some exponential pre-computation, performs better on ideal lattices than the best known algorithm for arbitrary lattices. We also present an algorithm to find short vectors in rank 2 modules, provided that we have access to some oracle solving the closest vector problem in a fixed lattice. The exponential pre-processing time and the oracle call make these two algorithms unusable in practice.The main scheme whose security might be impacted by SVP in ideal lattices is the GGH13multilinear map. This protocol is mainly used today to construct program obfuscators, which should render the code of a program unintelligible, while preserving its functionality. In a second part of this thesis, we focus on the GGH13 map and its application to obfuscation. We first study the impact of statistical attacks on the GGH13 map and on its variants. We then study the security of obfuscators based on the GGH13 map and propose a quantum attack against multiple such obfuscators. This quantum attack uses as a subroutine an algorithm to find a short vector in an ideal lattice related to a secret element of the GGH13 map
Cunha, de Almeida Eduardo. "Test et validation des systèmes pair-à-pair". Nantes, 2009. http://www.theses.fr/2009NANT2132.
Texto completoLe pair-à-pair (P2P) offre de bonnes solutions pour de nombreuses applications distribuées, comme le partage de grandes quantités de données et ou le support de collaboration dans les réseaux sociaux. Il apparaît donc comme un puissant paradigme pour développer des applications distribuées évolutives, comme le montre le nombre croissant de nouveaux projets basés sur cette technologie Construire des applications P2P fiables est difficile, car elles doivent être déployées sur un grand nombre de noeuds, qui peuvent être autonomes, refuser de répondre à certaines demandes, et même quitter le système de manière inattendue. Cette volatilité des noeuds est un comportement commun dans les systèmes P2P et peut être interprétée comme une faute lors des tests. Dans cette thèse, nous proposons un cadre et une méthodologie pour tester et valider des applications P2P. Ce cadre s’appuie sur le contrôle individuel des noeuds, permettant de contrôler précisément la volatilité des noeuds au cours de leur exécution. Nous proposons également trois différentes approches de contrôle d’exécution de scénarios de test dans les systèmes distribués. La première approche étend le coordonnateur centralisé classique pour gérer la volatilité des pairs. Les deux autres approches permettent d’éviter le coordinateur central afin de faire passer à l’échelle l’exécution des cas de tests. Nous avons validé le cadre et la méthodologie à travers la mise en oeuvre et l’expérimentation sur des applications P2P open-source bien connues (FreePastry et OpenChord). Les expérimentations ont permis de tester le comportement des systèmes sur différentes conditions de volatilité, et de détecter des problèmes d’implémentation complexes
El, Dick Manal. "P2P Infrastruture for content distribution". Nantes, 2009. http://www.theses.fr/2009NANT2127.
Texto completoLe Web connaît ces dernières années un essor important qui implique la mise en place de nouvelles solutions de distribution de contenu répondant aux exigences de performance, passage à l’échelle et robustesse. De plus, le Web 2. 0 a favorisé la participation et la collaboration entre les utilisateurs tout en mettant l’accent sur les systèmes P2P qui reposent sur un partage de ressources et une collaboration décentralisée. Nous avons visé, à travers cette thèse, la construction d’une infrastructure P2P pour la distribution de contenu. Toutefois, cette tâche est difficile étant donné le comportement dynamique et autonome des pairs ainsi que la nature des overlays P2P. Dans une première étape, nous nous intéressons au partage de fichiers en P2P. Nous abordons le problème de consommation de bande passante sous deux angles : l’inefficacité de la recherche et les transferts de fichiers longue distance. Notre solution Locaware consiste à mettre en cache des index de fichiers avec des informations sur leurs localités. Elle fournit également un support efficace pour les requêtes par mots clés qui sont courantes dans ce genre d’applications. Dans une deuxième étape, nous élaborons une infrastructure CDN P2P qui permet à tout site populaire et sous-provisionné de distribuer son contenu, par l’intermédiaire de sa communauté d’utilisateurs intéressés. Pour un routage efficace, l’infrastructure Flower-CDN combine intelligemment différents types d’overlays avec des protocoles épidémiques tout en exploitant les intérêts et les localités des pairs. PetalUp-CDN assure le passage à l’échelle alors que les protocoles de maintenance garantissent la robustesse face à la dynamicité des pairs. Nous évaluons nos solutions au travers de simulations intensives ; les résultats montrent des surcoûts acceptables et d’excellentes performances, en termes de taux de hit et de temps de réponse
Belblidia, Nadjet. "Capacité des réseaux opportunistes : caractérisation et impact sur la dissémination de contenus volumineux". Paris 6, 2012. http://www.theses.fr/2012PA066064.
Texto completoA common assumption in intermittently-connected (or opportunistic) mobile networks is that any contact has enough capacity to transfer any amount of data. Although such an assumption is reasonable for analytical purposes and when contents are small, it does not hold anymore when users produce contents that are larger than the contact capacity. In the first part of this thesis, we define and evaluate the surround indicator as a metric to exhibit a contact's surrounding environment in opportunistic networks. Whereas communication opportunities are limited in terms of both duration and surrounding environment, users conversely generate, consume, and share contents that are becoming increasingly larger. In such a situation, content-sharing solutions must be reformulated to enable exchanging large contents. Users must slice data and send fragments separately, which leads to a better use of short-lived contacts and promotes progressive dissemination of large contents. The main question here is to design the best strategy for deciding which piece(s) to transmit whenever nodes meet. We present the design and evaluation of PACS, a completely distributed algorithm that selects pieces to transfer based on a local view of their popularity. Finally, we present some experimental results obtained using PePiT, an Android application based on PACS that enables the dissemination of multimedia files among collocated Android devices in ad hoc mode. Then, we go one step further in the investigation of large content dissemination challenges in opportunistic networks. We argue that uniform random inter-content selection may not be sufficient in real-world deployment. We propose EPICS, a distributed strategy that enables fulfilling dissemination policy objectives. EPICS is based on the grey relational analysis to weight content selection. In our study, we use EPICS to reduce the dissemination delay variability due to the uniform random inter-content selection
Nafa, Mehdi. "Optimisation des applications de streaming peer to peer pour des réseaux ad hoc mobiles". Thesis, Evry-Val d'Essonne, 2009. http://www.theses.fr/2009EVRY0010/document.
Texto completoVideo content production has reached, nowadays, a big volume of traffic over the internet. Emerging social and professional networks (i.e. Facebook) and video portals (i.e. Youtube) acted as veritable accelerators for this phenomenon. In addition to IPTV and VoD applications, personal video sharing is also in the run. Our initial concern in this thesis was infrastructure wireless networks. We were focusing on how to provide a seamless mobile multimedia streaming service during horizontal handovers over cellular WLAN networks. This includes the proposal of a prediction based buffering scheme to cope with the video service disruption during the blackout periods. The work ended with a comparison between simulated and real test-bed implemented results. After file sharing and IP telephony, p2p streaming applications are getting a great concern from both academia and industry. The main goal of this technology is to allow nodes to cooperate and exchange contents among themselves. A lot of p2p streaming applications are currently used, over the Internet, for both video on demand and real-time streaming services like IPTV such as PPStream, UUSee, SopCas, TVants and Joost. At the same time we are seeing the development of new type of infrastructure-less communications using different types of devices PDA, telephones, computers, etc called Mobile Ad Hoc Networks. With this communication technology, networks can be created spontaneously at any place (home, office, street, bus, etc.). In a second phase our aim was to show how these MANET and P2P technologies can stimulate the emergence of new types of experience sharing in the society. We can easily imagine a scenario where mobile users build their own swarm, without resorting to the infrastructure, to exchange videos among them with no cost. Relying on their built-in wireless communication interfaces, they form a spontaneous network based on their preferences and including their friend, colleagues, etc. The two last contribution chapters are targeting the modeling and simulation of a mobile p2p streaming solution for MANETs. Relying on a mobility model based on the social communities we have shown the feasibility of P2P streaming over MANETs
Riahla, Mohamed Amine. "Contributions au routage et l'anonymat des échanges dans les réseaux dynamiques". Limoges, 2013. http://aurore.unilim.fr/theses/nxfile/default/092038da-e61a-46b8-81d6-5690d2cbece3/blobholder:0/2013LIMO4051.pdf.
Texto completoThe quick development of internet technologies gave birth to new types of network architectures with highly decentralized services that are organized independently. These characteristics have a real advantage : the deployment and implemetion are rapid and inexpensive for this type of networks. But in return, these networks can lead to difficulties when setting-up some services such as routing and security in general. In this thesis, we have taken as a case study P2P networks and ad hoc networks. We propose in this paper a set of contributions that we classify into two parts : the exchange anonymity in a P2P network and routing in an ad hoc networks
Al, Sukkar Ghazi. "Discovering the synergy between wireless ad hoc routing protocols and peer-to-peer abstractions". Evry, Institut national des télécommunications, 2008. http://www.theses.fr/2008TELE0018.
Texto completoNowadays the rapid developments in most technologies, such as WiFi, WiMax, Bluetooth, etc. Promote the use of wireless communications in every daily life. Though cellular networks have been considered as the main wireless media for data and voice communications during the last few decays, through, their first and second generations, they have failed to provide seamless applications to mobile users except for voice and low data rate services. On the other hand, with the rapid growth of the Internet, a huge number of applications require high data rates such as audio and video streaming, voice over IP, video conferencing services, etc. Current use of wireless networking is generally limited to a single-hop wireless connection, or access link, connecting a mobile or nomadic terminal to a wired gateway. The transition from such single-hop networks to multi-hop wireless networks introduces an abundance of interesting and challenging problems. Multi-hop wireless networks are expected to play an important role in future communications, already, non-military technologies and applications seem to point towards future networks such as: Ad hoc networks, Mesh Networks, Sensor Networks, and Vehicular Networks. However, such networks are associated with a number of challenging problems, several of which are addressed in the literature; one of the most important is the design of routing protocols. There are some barriers that make the design of such routing protocols a tough task. On the other side, the increased demand on traditional internet services imposes the appearance a new type of services which try to avoid any central point of dependence, these services need to form an overlay network built on top of the existing IP network called Peer-to-Peer overlay network (P2P overlay). Such services have gained popularity as a mechanism for users to share files without the need for centralized servers. A P2P network provides a scalable and fault-tolerant mechanism to locate nodes anywhere on a network without maintaining a large amount of routing state. This allows for a variety of applications beyond simple file sharing, which include multicast systems, anonymous communications systems, web caches, and new P2P IP Telephony systems such as Skype and P2P SIP. Our aim is to provide a way to discover the synergy between P2P overlay networks and Multi-hop wireless networks in order to be able to design better routing protocols for these kinds of networks, and apply P2P applications on top of these networks in an optimized way. Therefore, in this thesis we propose an addressing and routing mechanism that address part of the challenges faced by Multi-hop wireless networks, this mechanism acts as a standalone network layer that facilitate the interaction with the P2P applications in a way that minimizes the overall overhead, which in the typical solutions result from the need to implement and maintain two separate routing tables, one serve the P2P abstraction, while the other is the one implemented at the network layer. In the first part of this dissertation we introduce PARTY protocol which is intended to be applied in environments with large number of MANET nodes with high density, where the scalability of the routing protocol plays an important role. We also study the security issues in this protocol in order to prevent malicious attacks. In the second part, we propose MeshPARTY as a mobility management solution in Mesh networks. Finally, we propose SenPARTY as an efficient mechanism for data-centric storage in Sensor networks. The reliability and the efficiency of each of the three solutions have been demonstrated by both analytical and simulation studies where we compared them to the legacy protocols
Jégou, Arnaud. "Réseaux sociaux implicites et explicites, exploiter leur puissance grâce à la décentralisation". Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S069/document.
Texto completoContent personalization became an important functionality on the Internet, as it helps users to filter out uninteresting content. These systems collect a lot of data to provide accurate recommendations. This implies that the users loose control over their data, which causes a problem of privacy. Peer-to-peer (P2P) systems offer an interesting alternative to centralized services. In these systems, each user is responsible for her own data and control which ones are used by the system. Nevertheless, these systems solve only partially the privacy issue as, in general, all users of the system can access the data of the other users. In addition, it is difficult to know the true identity of users, and thus it is difficult to trust them. Thus is a problem in a context such as an online marketplace, such as eBay. In a P2P context, it is difficult to ensure that a user is really who she says she is, and that she will do her part of the job. Despites these weaknesses, we believe that P2P is the best way to solve the privacy issue. It is however necessary to improve P2P systems in order to better protect the users data and increase the trust between users. In this thesis we present four contributions going in that direction. The first one, TAPS, provides users with an estimation of the trustworthiness of other users based on information extracted from a social network, as well as a path linking the two users in this network. For example, TAPS will inform a user, Bob, that another user, Carol, is the sister of a colleague of his wife, Alice. Thus, Bob knows the identity of Carole and knows if he can trust her. The second one, PTAPS, is an alternative version of TAPS preserving the users' privacy. In TAPS, users provide the system with their list of friends. In PTAPS this information is hidden and only accessible by the user's friends. The third one, FreeRec, is a personalization system ensuring the users' anonymity. Privacy issues in P2P systems are mainly caused by the fact that it is possible to associate the action of a user with her identity. A solution is to hide the user's identity to the other users. FreeRec provides recommendations while ensuring users's anonymity thanks to onion routing. The last contribution, DPPC, is an algorithm hiding users' data in a recommendation system. Users data can contain precise information about the user. It has been showed that these data are sometimes enough to discover the user's true identity. DPPC hides these data while allowing the user to receive recommendations
Monnier, Damien. "Dynamique de mise en place des réseaux d'intrusions sableuses dans les bassins sédimentaires : impact sur l'évolution post-dépôt des réservoirs et le réseau de migration associé". Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20006.
Texto completoSand intrusions (or injectites) are most often the product of post-depositional remobilization of sand leading to its injection into the surrounding rocks. While injectites were recognized for the first time nearly 200 years ago, their emplacement process has been studied for a couple of decades only, since the concepts of deep sea depositional environments have allowed us to better understand their emplacement processes. However, these processes are still relatively poorly understood. Our approach is based on the study of injectites in the Lower Congo Basin from seismic and well data, which we compare to a fossil system in the SE France basin. We have shown that:(1) In buried turbidite channel systems draping deposits on the channel flanks and terraces of channels have the same geophysical signature as ‘wing-like' injectites. Finally, the only criterion for identifying seismic injectites is the presence of bedding-discordant seismic reflections, and in the best case the associated uplift of the overlying seismic reflectors.(2) Seismic-scale conical and saucer-shaped sand injectites have been identified in the Lower Congo Basin. The remobilization is likely due to overpressuring induced by the buoyancy effect of hydrocarbons trapped in the margins of a lobe buried underneath 160 m of sediment, followed by the sudden injection of fluidized sand associated with fault reactivation of faults (with a possible role of nearby salt diapirs).(3) A network of injectites (dykes, sills/wings and laccoliths) was formed in the Vocontian basin during the late Albian and/or early Cenomanian, from a lower-middle Albian turbidite channel. The emplacement is probably due to the early compartmentalization of the channel during its burial and the increase of the sedimentation rate generating overpressure; and the subsequent large influx of deep fluids triggering injection. The injection of sand was polyphased: a first episode formed the sills and another emplaced the dykes. Sills/wings and dykes propagated about 2 km laterally away from the parent sand body and about 200 m up to the surface, revealing a much more extended lateral than vertical reach, contrary to the classically accepted idea from the interpretation of seismic data.(4) The emplacement of this large network of injectites was governed by hydrofracturing. Therefore, its morphology is dependent on the host rock heterogeneity (isotropy, fractures), the paleo-stress orientation (σ3 = NW-SE) and the burial depth of the source (300-600 m) at the time of injection. The study of this fossil network allows us to define the relationship between morphology of the injected network and stress state at the time of injection. This relationship can be extrapolated to constrain the morphology of subsurface networks beyond seismic visibility.(5) Sands injected into low permeability lithologies bear evidence to a major event of fluid escape in the studied basin, but also channeled fluids long after their formation. In this way, injectites both attest to specific episodes of fluid migration in sedimentary basins and contribute to long-lived re-routing of migrating fluids once emplaced.The injection of sand is associated with the sudden escape of fluids, probably resulting from a significant tectonic and/or sedimentary event; in addition, the architecture of injectite networks is governed by the local paleo-stress and heterogeneity in the host rock. Consequently, characterizing injectite networks is an important step in understanding the plumbing systems of continental margins, i.e. the post-depositional evolution of sedimentary basins