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Villain, Benjamin. "Nouvelle génération de contrôleur d'accès réseau : une approche par réseaux logiciels". Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066663.
Pełny tekst źródłaThis thesis presents the importance of cross-layer network information for network applications in the context of network access control. The dissertation exposes a novel architecture in which a network access controller is mutualized in the Cloud. This architecture allows to address a key market segment for clients unwilling to buy expensive hardware to control their network. Multiple challenges come into play when hosting the controller remotely. Indeed cross-layer information are no longer available which prevents the controller from correctly controlling users activity. A first implementation to share cross-layer information is presented in chapter 2. It leverages specialized session border controllers to send these data in the application protocol, here HTTP. Then chapter 3 presents an innovative solution for the cross-layering problem which allows to intrumentalize network flows with SDN protocols. The solution focuses on a web portal redirection but is extendable to any kind of protocols. The implementation permits to intercept and modify flows in order to input cross-layer data within another network protocol. This solution was implemented in the OpenDaylight OpenFlow controller and shows great results. The mutualized approach coupled with the SDN cross-layer framework allow to build flexible networks with almost no configuration of on-site equipments. The central network controller reduces the overal cost of the solution by being mutualized among multiple clients. Moreover, having the ability to intrumentalize network traffic in software allows to implement any kind of custom behavior on the runtime
Villain, Benjamin. "Nouvelle génération de contrôleur d'accès réseau : une approche par réseaux logiciels". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066663/document.
Pełny tekst źródłaThis thesis presents the importance of cross-layer network information for network applications in the context of network access control. The dissertation exposes a novel architecture in which a network access controller is mutualized in the Cloud. This architecture allows to address a key market segment for clients unwilling to buy expensive hardware to control their network. Multiple challenges come into play when hosting the controller remotely. Indeed cross-layer information are no longer available which prevents the controller from correctly controlling users activity. A first implementation to share cross-layer information is presented in chapter 2. It leverages specialized session border controllers to send these data in the application protocol, here HTTP. Then chapter 3 presents an innovative solution for the cross-layering problem which allows to intrumentalize network flows with SDN protocols. The solution focuses on a web portal redirection but is extendable to any kind of protocols. The implementation permits to intercept and modify flows in order to input cross-layer data within another network protocol. This solution was implemented in the OpenDaylight OpenFlow controller and shows great results. The mutualized approach coupled with the SDN cross-layer framework allow to build flexible networks with almost no configuration of on-site equipments. The central network controller reduces the overal cost of the solution by being mutualized among multiple clients. Moreover, having the ability to intrumentalize network traffic in software allows to implement any kind of custom behavior on the runtime
Ben, Fredj Mohamed Slim. "Un Contrôle d'admission pour les flots IP dans un réseau multiservices". Versailles-St Quentin en Yvelines, 2002. http://www.theses.fr/2002VERS003V.
Pełny tekst źródłaBasmadjian, Robert. "Un protocole contrôle de réplique d'une structure d'arborescence arbitraire". Toulouse 3, 2008. http://thesesups.ups-tlse.fr/460/.
Pełny tekst źródłaIn large distributed systems, replication is the most widely used approach to offer high data availability, low bandwidth consumption, increased faulttolerance and improved scalability of the overall system. Replication-based systems implement replica control (consistency) protocols that enforce a specified semantics of accessing data. Also, the performance depends on a host of factors chief of which is the protocol used to maintain consistency among the replicas. Several replica control protocols have been described in the literature. They differ according to various parameters such as their communication costs, their ability to tolerate replica failures (also termed as their availability), as well as the load they impose on the system when performing read and write operations. Moreover these replica control protocols can be classified into two families: some protocols assume that replicas of the system are arranged logically into a specific structure (Finite Projective Plane, Grid or Tree) whereas others do not require any specific structure to be imposed on the replicas. In this thesis, at group ASTRE of IRIT and under the supervision of professor Jean-Paul Bashoun, we are interested in studying the replication protocols that arrange logically the replicas into a tree structure and investigate how to circumvent the drawbacks of the root replica as the existing treestructured protocols suffer from the root replica's bottleneck
Francomme, Jackson. "Propositions pour un protocole déterministe de contrôle d'accès et de routage avec économie d'énergie dans les réseaux ZigBee". Phd thesis, Université Toulouse le Mirail - Toulouse II, 2008. http://tel.archives-ouvertes.fr/tel-00324196.
Pełny tekst źródłaElbiaze, Halima. "Application des techniques de contrôle d'accès à la garantie de QoS dans un réseau optique multiservice". Versailles-St Quentin en Yvelines, 2002. http://www.theses.fr/2002VERS004V.
Pełny tekst źródłaViéron, Jérôme. "Codage scalable et contrôle de congestion pour transmission vidéo sur réseaux hétérogène". Rennes 1, 2003. https://hal.archives-ouvertes.fr/tel-01131930.
Pełny tekst źródłaDiego, Maza William David. "Contrôle de trafic et gestion de la qualité de service basée sur les mécanismes IP pour les réseaux LTE". Thesis, Télécom Bretagne, 2016. http://www.theses.fr/2016TELB0406/document.
Pełny tekst źródłaThe mobile data landscape is changing rapidly and mobile operators are today facing the daunting challenge of providing cheap and valuable services to ever more demanding customers. As a consequence, cost reduction is actively sought by operators as well as Quality of Service (QoS) preservation. Current 3GPP standards for LTE/EPC networks offer a fine tuning QoS (per-flow level), which inherits many characteristics of legacy telco networks. In spite of its good performance, such a QoS model reveals costly and cumbersome and finally, it remains very rarely deployed, thereby giving way to basic best-effort hegemony. This thesis aims at improving QoS in mobile networks through cost-effective solutions; To this end, after an evaluation of the impact and cost of signaling associated with the standard QoS model, alternative schemes are proposed, such as the IP-centric QoS model (per aggregate) inspired from the DiffServ approach widely used in fixed IP networks. This model provides a simple, efficient and cost-effective IP level QoS management with a performance level similar to standardized solutions. However, as it requires enhancements in the eNB, this scheme cannot be expected in mobile networks before a rather long time.Thus, we introduce Slo-Mo, which is a lightweight implicit mechanism for managing QoS from a distant point when the congestion point (e.g. eNB) is not able to do it. Slo-Mo creates a self-adaptive bottleneck which adjusts dynamically to the available resources taking advantage of TCP native flow control. Straightforward QoS management at IP level is then performed in the Slo-Mo node, leading to enhanced customer experience at a marginal cost and short term
Saba, Ghassan. "Protocoles multipoint et interconnexion de réseaux FIP". Vandoeuvre-les-Nancy, INPL, 1996. http://docnum.univ-lorraine.fr/public/INPL_T_1996_SABA_G.pdf.
Pełny tekst źródłaZagrouba, Rachid. "Contrôle de la mobilité et de la QoS dans les réseaux cellulaires tout IP". Télécom Bretagne, 2007. http://www.theses.fr/2007TELB0051.
Pełny tekst źródłaThis study deals with QoS and mobility management in the wireless access networks. It is interested in the definition of wireless mobile IP networks both on the access network and the core network. The core network is supposed built on DiffServ and Mobile IP Protocol. We are thus focus mainly in the access network and in particular in the QoS signaling and handover management. The first part of this thesis consists in studying the basic concepts and proposals of QoS and mobility management in wireless IP networks. Then, we give an analysis and comparison of the main frameworks. Next, we define the new challenges for wireless operators and we address some important issues that arise when managing QoS within a wireless IP network. Lastly, we propose a new protocol to provide a set of scenarios and functions needed to couple QoS and mobility management. The proposed protocol, called QoS and Micro Mobility Management (Q3M), enables a network operator to use its network resources more efficiently, increase network performance and minimize signaling traffic. The implementation of Q3M protocol on the France Telecom R&D (Rennes) testbed, as well as the analytical and simulation results, show that Q3M protocol has a good performance in terms of delay establishment of QoS session and blocking probability. The performance of Q3M protocol is very reasonable compared to other related works. The Q3M advantage becomes more important when mobility is high and the network is congested
Dorel, Jean-Luc. "Techniques d'interconnexion et de contrôle des ressources dans un environnement de réseaux hétérogènes". Versailles-St Quentin en Yvelines, 1995. http://www.theses.fr/1995VERS0002.
Pełny tekst źródłaBournelle, Julien. "Vers un système d'authentification intégrant la configuration dynamique de la mobilité IPv6 et la prise en compte des déplacements". Evry, Institut national des télécommunications, 2004. http://www.theses.fr/2004TELE0005.
Pełny tekst źródłaIn the next future, equipments will access to the Internet while being mobile. One of the possible solution to remain reachable while moving is to use the new standardized IEFT protocol named Mobile IPv6. To achieve this goal, the equipment owns a home address and a home agent which is in charge of relaying IPv6 packets to its current location. To ease deployment of this protocol, a solution is needed in order to dynamically allocate those parameters and to bootstrap in the same time an IPsec security association between the mobile and its allocated home agent. In this PhD work, we proôsed to use the authentificationphase and thus the AAA infrastrructure to bootstrap the Mobile IPv6 service. In a first approach, we proposed a new application to the Diameter AAA Protocol to authenticate and configure Mobile IPv6 equipment. This proposition was implemented but due to some inherent deployment limitations we proposed a new approach which uses the EAP protocol to carry the needed Mobile Ipv6 parameters between the home domain and the IP client. These two propositions was submitted to the IETF. While authenticated and configured, the mobile is likely to move in the IP access network. In a mobile environment using PANA, IP clients risk to be re-authenticated from scratch by a new authentication agent while changing of access routers. To avoid this, we proposed using CTP to transfer the state created at the previous attachment to the new attachment. This proposition was also submitted to the IETF
Corbel, Romuald. "Évolution des protocoles de transport du point de vue de l'équité". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0160.
Pełny tekst źródłaThis thesis is in the context of measuring congestion on the network and the evolution of transport protocols. Changes are continually being made to meet the needs of users and new services. Congestion is one of the most critical issues because it has an impact on the performance of Internet networks, hence the need for congestion control algorithms to prevent or remove it. Today, no algorithm perfectly meets the expected requirements, and a lot of research is underway. Nevertheless, these new algorithms can affect network fainress since the behaviour of the transport protocol can change radically depending on the congestion control algorithm used in the endpoints. In addition, in recent years, transport protocols have undergone major changes. A recent significant exampleis Quick UDP Internet Connections (QUIC), a protocol introduced by Google, which aims to replace two widely used transport and security protocols, Transmission Control Protocol (TCP) and Transport Layer Security (TLS). QUIC is implemented in user applications (rather than in the operatingsystem kernel). It is designed to be resistant to ossification and therefore more versatile. This makes content providers, such as Google, hegemonic about the data rate of their users. Due to the progressive development of congestion control algorithms and the evolving nature of transport protocols, new challenges arise in fairness management. This is why, in this thesis, we focused on the development of a test platform to measure network fairness based on the flow rate of the different flows. In addition, in order to characterize fairness as perceived by a user, we focused on determining an impartial procedure for assessing fainress during an entire session of a transport flow (called Session Fairness Assessment(SFA) and Weighted Session Fairness Assessment(WSFA)). Based on these elements, we specifically analyzed the fairness of the protocols when TCP and QUIC flows coexist on a fixed and mobile network. In our fairness assessments, weidentified the impact of aspects of QUIC implementation such as: emulating multiple TCP connections, limiting the size of congestion windows and using the hystart option. The results show that these mechanisms have a strong influence on fairness on both fixed and mobile networks. Indeed,a wrong setting of the default parameters of these mechanisms or the activation of the hystart option can affect the performance of transport protocols and therefore fainress. With regard to the evaluation of congestion control algorithms, the results show that the fainress between two different algorithms depends on the network configuration. This conclusion demonstrates that a measurement procedure, such as the one presented in this thesis, is relevant to conducting the fairness assessment. In this thesis we can conclude that the lack of standardization, for example of emulating multiple TCP connections in QUIC, leads us to question more broadly how QUIC’s design philosophy takes fairness into account. In addition, the results obtained on the evaluation of the fainress of congestion control algorithms allow us to question the fainress evaluation of several contributions when it is not tested in enough network configurations
Luu, Thanh Tra. "Etude et mise en oeuvre d'une signalisation IP universelle". Paris, ENST, 2006. http://www.theses.fr/2006ENST0046.
Pełny tekst źródłaThe future generation of the Internet requires a powerful control plane wherein the signaling plays a key role in enabling information exchanges between the network elements to provide the existing and future network services. The thesis develops a generic IP signaling protocol, referred to as GISP, which provides common functionalities required by most IP signaling protocols including state management, transport and security services. The GISP implements a soft-state approach to manage the signaling states established within the network elements. In particular, a new soft-state management mechanism is proposed to significantly reduce the signaling traffic as well as the CPU resource consumption allowing the GISP to meet scalability in the number of signaling sessions. The GISP supports the signaling messages transport between the network elements. A variety of transport services have been specifically developed for GISP such as message bundling, message fragmentation, path MTU discovery, partially reliable transport and congestion control. These services have been designed to provide performance, flexibility and robustness for the generic signaling protocol. Finally, the GISP provides security services to protect the message transport as well as the network from vicious attacks. A GISP implementation has been realized in the context of the thesis to experience the GISP functionalities and evaluate its performance aspects
Pham, Van Quan. "Cloud-native optical network automation platforms". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAS005.
Pełny tekst źródłaOptical communication management and control are transforming to integrate new capabilities such as intent-based network management, closed-loop control automation, and multi-stakeholder orchestration. These capabilities are driven by the new connectivity requirements between data centers to enable future generations of services: Beyond 5G (B5G) and 6G applications offered at the edges of optical networks. The next generation of optical network management and control architectures will entail Software-Defined Networking (SDN) principles for the disaggregation of future optical systems. The current optical network controllers and managers are intrinsically proprietary and, consequently, restricted in openness, scalability, and flexibility. This Ph.D. thesis investigates and proposes breakthrough software architectures with: (i) their control functions for the optical systems and (ii) their management functions for optical connection services of Open Disaggregated Optical Networks. After explaining SDN architectures in the context and the constraints of optical switching and transmission networks, the thesis explains the challenges of current optical networks to transition towards the control of Partially Disaggregated Optical Networks as a first step and the control of Fully Disaggregated Optical Networks as the ultimate step. Novel software-defined optical network automation platforms with control functions based on micro-services are described pragmatically, considering open-source software frameworks and several open forums providing their languages and their data models. Their protocols are being developed for devices, network topology, and communication services. Next, the thesis described how control functions are designed as cloud-native network functions (CNF), enabling continuous integration and continuous development of cloud-native optical networking platforms. Automated optical channel path computation functions as services a re first addressed. These optical channel path computation services are described by explaining how the routing constraints defined by the evolutions of optical system capabilities can be integrated into the path computation engines (PCE). Several PCE algorithms for optical channel routing and spectrum allocation are presented, and their performances are compared in terms of reasonable or possibly optimal spectrum allocation.Subsequent to the concepts of automated optical channel path computation functions as services, the thesis proposes automated optical channel defragmentation functions as services to re-arrange the placements of optical channels for better and possibly optimal use of the spectrum grid to gain resources.From the evaluations of these different container-based optical control functions, several optical channel control automation scenarios are described to prove their concepts using a network bench in a lab and demonstrate the potential applications of optical CNFs.Finally, the thesis concludes with the synthesis of these research works and the future challenges to make the control and the management of optical networks more unified and streamlined to enable optical communications to be designed and an asset as connectivity services for future generation services
Zhang, Xiaofei. "Contrôle de transmission multi-chemin et gestion de mobilité pour protocoles de transport multihoming". Paris 6, 2012. http://www.theses.fr/2012PA066130.
Pełny tekst źródłaMost of mobile devices today are equipped with multiple network interfaces that could be connected to different network and obtain multiple IP addresses. In this dissertation, we investigate the multihoming problems at transport layer to improve the end-to-end performance in wireless networks. Moreover, the coordination between multihoming and mobility management is studied which permit us to propose a cooperative mobility management for an environment Post-IP. Firstly, we propose a cross-layer solution for performance optimization with the Concurrent Multipath Transfer (CMT) extension of SCTP in wireless networks. Two parameters, Frame Error Rate (FER) at the link layer and Round Trip Time (RTT) at the transport layer are used to evaluate the path conditions. The simulation results show that our proposal improves the goodput. Secondly, we focus on the heterogeneous wireless links. We chose Kalman filter for the estimation of path conditions. The simulation results show that our proposal reduces the reordering degree and increases the total goodput. Finally, a cooperative mobility management architecture is proposed for Post-IP. Multihoming and end-to-end features are analyzed to present the proposal of Multihoming-based Cooperative Mobility Management (MCMM). The cooperative mobility management optimizes the handover delay in the heterogeneous access networks. The MCMM is implemented in C++ under Linux with a test-bed. The experimental results show that the handover delay can be reduced by sending update messages over the interface of the fastest path
LARRIEU, Nicolas. "Contrôle de congestion et gestion du trafic à partir de mesures pour l'optimisation de la QdS dans l'internet". Phd thesis, INSA de Toulouse, 2005. http://tel.archives-ouvertes.fr/tel-00009745.
Pełny tekst źródłaJourjon, Guillaume. "Toward a versatile transport protocol". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2008. http://tel.archives-ouvertes.fr/tel-00309959.
Pełny tekst źródłaCousin, Bernard. "Méthodologie de validation des systèmes structurés en couches par réseaux de Petri : application au protocole Transport". Phd thesis, Université Pierre et Marie Curie - Paris VI, 1987. http://tel.archives-ouvertes.fr/tel-00864063.
Pełny tekst źródłaWan, Haitao. "Efficacité énergétique, synchronisation et contrôle de puissance pour l'implémentation des communications coopératives dans les réseaux de capteurs sans fil". Nantes, 2010. http://archive.bu.univ-nantes.fr/pollux/show.action?id=cafed1b3-99cf-40b5-916d-617fa4edbee1.
Pełny tekst źródłaIn this dissertation, we explore the energy efficiency and low complex implementation of cooperative schemes in wireless sensor networks. Considering the requirement on signal arrival time synchronization, we proposed a physical layer synchronization scheme for the distributed MISO cooperative communication in wireless sensor networks. The proposed scheme is adequate for the cooperative communication but introduces less complexity to the network design. It provides better BER performance in the existence of initial synchronization error. According to the simulation results, it is supposed to be practically implemented in the sensor nodes. Upon this assumption, optimal power allocation strategies for AF cooperative relaying scheme and distributed MISO cooperative scheme are proposed for cooperative communication in wireless sensor networks. With a given requirement on BER performance, they help to minimize the total transmit power in Rayleigh fading channel. Moreover, without direct link between the source and destination nodes, we proposed two energy efficient cooperative strategies to incorporate the AF cooperative relaying and distributed MISO cooperative schemes. A heuristic policy to select the cooperative nodes and choose the appropriate cooperative strategy is derived. Furthermore, we analyzed the energy efficiency of three error control protocols considering SISO AWGN for short distance communication and MISO Rayleigh fading for long distance communication. We proposed thresholds of the coding gain for various code rates to make the hybrid ARQ protocol more energy efficient
Nassrallah, Rabih. "Modèle domanial pour la gestion et le contrôle de la qualité de service de bout en bout dans les réseaux IP hétérogènes". Troyes, 2007. http://www.theses.fr/2007TROY0014.
Pełny tekst źródłaThe uses of Internet network extended in last years by integrating new services IP. Contrary to the applications known as elastic, these advanced services induce constraints for their operations. However, traditional network IP (Best Effort) was conceived to transport information without guarantee neither of time nor of availability of bandwidth. Several evolutions of the network however made it possible to take into account the requirements for quality of service of the applications in a single domain managed overall by an operator. In this document, we are interested in the problem of the en-to-end quality of service over multiple domains networks. We focus on the heterogeneous aspect of the quality of service control over theses domains that can lead to an incoherent treatment of the IP packet of the same application through the various networks thus resulting a degradation of the service. This thesis proposes a model for the control of the en-to-end quality of service and the available bandwidth management over various networks. This model must help the operators to offer a homogeneous en-to-end service to flows in a real environment such as the Internet. Our model is based on an evaluation of the en-to-end quality of service prior to the flow admission in the network, associated to a degradation monitoring over all the duration of the service
Kabir-Querrec, Maëlle. "Cyber sécurité des systèmes industriels pour les smart-grids : détection d'intrusion dans les réseaux de communication IEC 61850". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT032/document.
Pełny tekst źródłaInformation and Communication Technologies have been pervading Industrial Automation and Control Systems (IACS) for a few decades now. Initially, IACS ran proprietary protocols on closed networks, thus ensuring some level of security through obscurity and isolation. Technologies and usages have evolved and today this intrinsic security does not exist any longer, though. This transition is in progress in the electricity domain, the power infrastructure turning into the "smart grid".The IEC 61850 standard is key to the smart grid development. It is aimed at making interoperability possible in ``Communication networks and systems for power utility automation''. It thus defines a common data object model and a stack of protocols answering different purposes.Although the cyber risk in IACS is now widely acknowledged, IEC 61850 does not address cyber security in any way whatsoever.This work tackles the question of cyber security through network intrusion detection in IEC 61850 networks, and more specifically in real-time GOOSE communications. The idea is to get the most out of the protocol specifications and system configuration while developing a tailored NIDS. This enables detection accuracy
Amadou, Ibrahim. "Protocoles de routage sans connaissance de voisinage pour réseaux radio multi-sauts". Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00763865.
Pełny tekst źródłaCridlig, Vincent. "Sécurité du plan de gestion des réseaux IP". Phd thesis, Université Henri Poincaré - Nancy I, 2006. http://tel.archives-ouvertes.fr/tel-00134670.
Pełny tekst źródłaVeron, Maxime Pierre Andre. "Scalable services for massively multiplayer online games". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066212/document.
Pełny tekst źródłaMassively 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
Youssef, Anis. "Réseau de communication à haut niveau d'intégrité pour des systèmes de commande-contrôle critiques intégrant des nappes de microsystèmes". Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2005. http://tel.archives-ouvertes.fr/tel-00111808.
Pełny tekst źródłaL'étude que nous avons effectuée sur des réseaux standard montre que les protections classiques à base de codes CRC ne permettent pas d'obtenir le niveau d'intégrité visé.
Pour l'atteindre, nous avons proposé une solution originale - fonction de contrôle évolutive - qui tire profit du fait que, pour les systèmes de commande-contrôle envisagés (systèmes à dynamique lente), l'intégrité est à considérer sur un lot de messages et non sur un seul message. La solution proposée a ensuite été validée via des simulations Matlab-Simulink.
Le cas d'étude utilisé est celui de systèmes de commande de vol du futur, en vue de pouvoir commander des nappes de milliers de micro-surfaces tels que des micro-spoilers.
Ghadi, Abderrahim. "Modèle hiérarchique de contrôle d'accès d'UNIX basé sur un graphe de rôles". Strasbourg, 2010. http://www.theses.fr/2010STRA6005.
Pełny tekst źródłaConcerning access control, can the following question be addressed : "Is the access control system decidable ?". In other words : is it true that starting from a safe state of protection, we can assume at any time that is no intrusion which will endanger our system ?. In order to answer this question, we propose to model the access control system in the form of a graph of roles. The roles, which represent the vertices of graph contain, according to the security-policy, certain number of privileges. Every privilege represents one or several access rights on a given object. We presented two methods of use of this graph : The first consists in using an algorithm, which we developed by basing itself on the algorithms of the theory of the graphs, permit to search all over the path of the graph in order to find illicit privilege transfer. The second consists in storing our graph in a directory LDAP, this which brings us to develop a new plan LDAP to represent our graph of roles
Sabouni, Imad. "Génération de modules dédiés aux circuits de communication de contrôle-commande : une étude de conception appliquée dans le cadre de la voiture sûre PROMETHEUS". Grenoble INPG, 1992. http://www.theses.fr/1992INPG0143.
Pełny tekst źródłaTurna, Ozgur Can. "Bandwidth allocation and energy efficiency solutions in optical access networks". Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0005/document.
Pełny tekst źródłaIn this thesis, general overview about PON systems is presented and existing PON mechanisms and classification are investigated. After, a novel dynamic bandwidth allocation algorithm for EPON is introduced. This proposed algorithm is named as “Half Cycling Dynamic Bandwidth Allocation-hcDBA” by the inspiration of its half cycling processing mode. Later, an improvement of hcDBA algorithm with early prediction mechanism is presented. As a result statement of the study, hcDBA algorithm performs better than existing mechanism in terms of packet loss ratio and access delays. Beside, simulation traffic behavior of EPON’s upstream channel has been investigated in order to support the decision of selecting suitable traffic generator in further studies. Energy conversation is one of the hot topics in telecommunication networks. Access networks constitute remarkable portion of the total energy consumption in telecommunication networks. ITU-T and IEEE organizations published recommendation for energy conversation in PONs. While, total energy consumption of ONUs is more than other equipment in fix access network the standards and most of the researches focused on saving energy at ONU side. In this thesis I focused on an energy efficiency method based on energy conversation on OLT side. The proposed method save energy by dynamically moving OLT cards to deep sleep mode according to the incoming and outgoing traffic loads
Veron, Maxime Pierre Andre. "Scalable services for massively multiplayer online games". Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066212.
Pełny tekst źródłaMassively 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
Trad, Abdelbasset. "Déploiement à grande échelle de la voix sur IP dans des environnements hétérogènes". Phd thesis, Nice, 2006. http://tel.archives-ouvertes.fr/tel-00406513.
Pełny tekst źródłaBen, Ameur Chiheb. "TCP Protocol Optimization for HTTP Adaptive Streaming". Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S127/document.
Pełny tekst źródłaHTTP adaptive streaming (HAS) is a streaming video technique widely used over the Internet. It employs Transmission Control Protocol (TCP) as transport protocol and it splits the original video inside the server into segments of same duration, called "chunks", that are transcoded into multiple quality levels. The HAS player, on the client side, requests for one chunk each chunk duration and it commonly selects the quality level based on the estimated bandwidth of the previous chunk(s). Given that the HAS clients are located inside access networks, our investigation involves several HAS clients sharing the same bottleneck link and competing for bandwidth. Here, a degradation of both Quality of Experience (QoE) of HAS users and Quality of Service (QoS) of the access network are often recorded. The objective of this thesis is to optimize the TCP protocol in order to solve both QoE and QoS degradations. Our first contribution consists of proposing a gateway-based shaping method, that we called Receive Window Tuning Method (RWTM); it employs the TCP flow control and passive round trip time estimation on the gateway side. We compared the performances of RWTM with another gateway-based shaping method that is based on queuing discipline, called Hierarchical Token Bucket shaping Method (HTBM). The results of evaluation indicate that RWTM outperforms HTBM not only in terms of QoE of HAS but also in terms of QoS of access network by reducing the queuing delay and significantly reducing packet drop rate at the bottleneck.Our second contribution consists of a comparative evaluation when combining two shaping methods, RWTM and HTBM, and four very common TCP variants, NewReno, Vegas, Illinois and Cubic. The results show that there is a significant discordance in performance between combinations. Furthermore, the best combination that improves performances in the majority of scenarios is when combining Illinois variant with RWTM. In addition, the results reveal the importance of an efficient updating of the slow start threshold value, ssthresh, to accelerate the convergence toward the best feasible quality level. Our third contribution consists of proposing a novel HAS-based TCP variant, that we called TcpHas; it is a TCP congestion control algorithm that takes into consideration the specifications of HAS flow. Besides, it estimates the optimal quality level of its corresponding HAS flow based on end-to-end bandwidth estimation. Then, it permanently performs HAS traffic shaping based on the encoding rate of the estimated level. It also updates ssthresh to accelerate convergence speed. A comparative performance evaluation of TcpHas with a recent and well-known TCP variant that employs adaptive decrease mechanism, called Westwood+, was performed. Results indicated that TcpHas largely outperforms Westwood+; it offers better quality level stability on the optimal quality level, it dramatically reduces the packet drop rate and it generates lower queuing delay
Medina, Ruiz Hamlet. "TCP and network coding : equilibrium and dynamic properties". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112165.
Pełny tekst źródłaCommunication networks today share the same fundamental principle of operation: information is delivered to their destination by nodes intermediate in a store-and-forward manner.Network coding (NC) is a technique that allows intermediate nodes to send out packets that are linear combinations of previously received information. The main benefits of NC are the potential throughput improvements and a high degree of robustness, which is translated into loss resilience. These benefits have motivated deployment efforts for practical applications of NC, e.g., incorporating NC into congestion control schemes such as TCP-Reno to get a TCP-NC congestion protocol. In TCP-NC, TCP-Reno throughput is improved by sending a fixed amount of redundant packets, which mask part of the losses due, e.g., to channel transmission errors. In this thesis, we first analyze the dynamics of TCP-NC with random early detection (RED) as active queue management (AQM) using tools from convex optimization and feedback control. We study the network equilibrium point and the stability properties of TCP-Reno when NC is incorporated into the TCP/IP protocol stack. The existence and uniqueness of an equilibrium point is proved, and characterized in terms of average throughput, loss rate, and queue length. Our study also shows that TCP-NC/RED becomes unstable when delay or link capacities increases, but also, when the amount of redundant packets added by NC increases. Using a continuous-time model and neglecting feedback delays, we prove that TCP-NC is globally stable. We provide a sufficient condition for local stability when feedback delays are present. The fairness of TCP-NC with respect to TCP-Reno-like protocols is also studied. Second, we propose an algorithm to dynamically adjust the amount of redundant linear combinations of packets transmitted by NC. In TCP-NC with adaptive redundancy (TCP-NCAR), the redundancy is adjusted using a loss differentiation scheme, which estimates the amount of losses due to channel transmission errors and due to congestion. Simulation results show that TCP-NCAR outperforms TCP-NC in terms of throughput. Finally, we analyze the equilibrium and stability properties of TCP-NCAR/RED. The existence and uniqueness of an equilibrium point is characterized experimentally. The TCP-NCAR/RED dynamics are modeled using a continuous-time model. Theoretical and simulation results show that TCP-NCAR tracks the optimal value for the redundancy for small values of the packet loss rate. Moreover, simulations of the linearized model around equilibrium show that TCP-NCAR increases the size of the TCP-Reno stability region. We show that this is due to the compensator effect of the redundancy adaptation dynamics to TCP-Reno. These characteristics of TCP-NCAR allow the congestion window adaptation mechanism of TCP-Reno to react in a smooth way to channel losses, avoiding some unnecessary rate reductions, and increasing the local stability of TCP-Reno
Bussard, Laurent. "Protocoles d'établissement de confiance pour objets communicants". Phd thesis, Télécom ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00000879.
Pełny tekst źródłaCécé, Gérard. "Vérification, analyse et approximations symboliques des automates communicants". Cachan, Ecole normale supérieure, 1998. http://www.theses.fr/1998DENS0008.
Pełny tekst źródłaTurna, Ozgur Can. "Bandwidth allocation and energy efficiency solutions in optical access networks". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0005.
Pełny tekst źródłaIn this thesis, general overview about PON systems is presented and existing PON mechanisms and classification are investigated. After, a novel dynamic bandwidth allocation algorithm for EPON is introduced. This proposed algorithm is named as “Half Cycling Dynamic Bandwidth Allocation-hcDBA” by the inspiration of its half cycling processing mode. Later, an improvement of hcDBA algorithm with early prediction mechanism is presented. As a result statement of the study, hcDBA algorithm performs better than existing mechanism in terms of packet loss ratio and access delays. Beside, simulation traffic behavior of EPON’s upstream channel has been investigated in order to support the decision of selecting suitable traffic generator in further studies. Energy conversation is one of the hot topics in telecommunication networks. Access networks constitute remarkable portion of the total energy consumption in telecommunication networks. ITU-T and IEEE organizations published recommendation for energy conversation in PONs. While, total energy consumption of ONUs is more than other equipment in fix access network the standards and most of the researches focused on saving energy at ONU side. In this thesis I focused on an energy efficiency method based on energy conversation on OLT side. The proposed method save energy by dynamically moving OLT cards to deep sleep mode according to the incoming and outgoing traffic loads
Khaldon, Hassan. "Architecture de contrôleur mémoire configurable et continuité de service pour l'accès à la mémoire externe dans les systèmes multiprocesseurs intégrés à base de réseaux sur puce". Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT051/document.
Pełny tekst źródłaThe ongoing advancements in VLSI technology allow System-on-Chip (SoC) to integrate many heterogeneous functions into a single chip, but still demand, because of economical constraints, a single and shared main off-chip SDRAM. Consequently, main memory system design, and more specifically the architecture of the memory controller, has become an increasingly important factor in determining the overall system performance. Choosing a memory controller design that meets the needs of the whole system is a complex issue. This requires the exploration of the memory controller architecture, and then the validation of each configuration by simulation. Although the architecture exploration of the memory controller is a key to successful system design, state of the art memory controllers are not as flexible as necessary for this task. Even if some of them present a configurable architecture, the exploration is restricted to limited sets of parameters such as queue depth, data bus size, quality-of-service level, and bandwidth distribution. Several classes of traffic co-exist in real applications, e.g. best effort traffic and guaranteed service traffic, and access the main memory. Therefore, considering the interaction between the memory subsystem and the interconnection system has become vital in today's SoCs. Many on chip networks provide guaranteed services to traffic classes to satisfy the applications requirements. However, very few studies consider the SDRAM access within a system approach, and take into account the specificity of the SDRAM access as a target in NoC-based SoCs. This thesis addresses the topic of dynamic access to SDRAM in NoC-based SoCs. We introduce a totally customizable memory controller architecture based on fully configurable building components and design a high level cycle approximate model for it. This enables the exploration of the memory subsystem thanks to the ease of configuration of the memory controller architecture. Because of the discontinuity of services between the network and the memory controller, we also propose within the framework of this thesis an Extreme End to End flow control protocol to access the memory device through a multi-port memory controller. The simple yet novel idea is to exploit information about the memory controller status in the NoC. Experimental results show that by controlling the best effort traffic injection in the NoC, our protocol increases the performance of the guaranteed service traffic in terms of bandwidth and latency, while maintaining the average bandwidth of the best effort traffic
Bellache-Sayah, Thiwiza. "Contrôle dynamique des communications dans un environnement v2v et v2i". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLV011/document.
Pełny tekst źródłaCooperative intelligent transport systems allow vehicles to communicate with each other as well as with the infrastructure in order to ensure the availability of information more reliably on vehicles, their positions and road conditions. This exchange of relevant information improves road safety, reduces traffic incidents and ensures efficient mobility of vehicles. IEEE 802.11p is standardized as the default technology for vehicle communications. In this context, the European ETSI standard addresses in particular road safety applications. To do this, it standardizes several types of messages such as CAM (Cooperative Awareness Message) and DENM (Decentralized Event Notification Message). CAMs are single-hop broadcast messages, sent by each vehicle containing information on its position, speed, direction, etc., in order to ensure lucid cooperation between other road users (including vehicles). The DENMs are sent when there is a detection of an event on the road, as in the case of an accident, traffic jams, etc. If necessary, multi-hop communication, using standardized routing algorithms, is implemented to disseminate these messages beyond the scope of the transmitter. The weakness of 802.11p lies in congestion of the radio channel due to the limited bandwidth (5.9 GHz). In order to compensate for this, ETSI proposed a framework for congestion control called DCC (Distributed Congestion Control). This allows the exchange of information, in particular the state of the radio channel, between the layers of the protocol stack. Thus, each communication protocol controls its own parameters to avoid congestion of the channel. In addition, many DCC congestion control approaches exist for CAM messages such as the control of the CAM generation period on the Facilities layer. Transmission power or data rate on the Access layer, etc. On the other hand, little works have been done on DENMs. In this regard, we proposed a DCC approach on the GeoNetworking layer which controls the routing parameters based on the state of the radio channel. An evaluation of the dual-DCC, namely CAM on Facilities and DENM on GeoNet, demonstrated the effectiveness of the proposed approach. In addition, some applications such as managing a fleet of vehicles require a localized control center that communicates with the fleet. For this type of exchange, a hybrid communication (IP and Geo) is necessary. Moreover, to ensure the fluidity of communication, the management of mobility is paramount. While remaining within the framework of the Mobile IP architecture, we propose our approach of addressing which constitutes a routable IP address with a geonetworking address, which makes it possible to deal with the problem of accessibility of vehicles moving on the road from of an entity on the Internet. Unlike Mobile IP, our approach reduces the overhead of signaling. This is done by partitioning the road into routing area (RA) in such a way that the access to the Internet is via a RSU-FA gateway that controls the RA. Each RA regroups a number of RSUs
Diaz, Nava Mario. "Proposition d'une méthodologie de conception de circuits intégrés de communication : réalisation d'un communicateur pour le réseau local FIP". Phd thesis, Grenoble INPG, 1986. http://tel.archives-ouvertes.fr/tel-00320454.
Pełny tekst źródłaBenarif, Samir. "Plate-forme multi-agent pour la reconfiguration dynamique des architectures logicielles". Versailles-St Quentin en Yvelines, 2006. http://www.theses.fr/2006VERS0038.
Pełny tekst źródłaA dynamic change to architecture is an active area of research within the software architecture community. The objective of all architecture reconfiguration, adaptation and evolution is the improvement of the quality attributes of the software architecture. Only recently the reconfiguration of software architecture at runtime has grown up considerably for the construction of reliable evolutionary systems. The structure of these systems is dynamic and continuously changing. Consequently, architectures must have the ability to react to events and perform architectural changes autonomously. In this thesis, we provide a new approach based on software multi-agent platform. Such agents are used to supervise the architecture, gather information from it and its environment, capture dynamic changes, and manage them. They monitor the components dynamically and adapt them to structural changes in the architecture. They evaluate dynamically the quality attributes of the architecture. This evaluation will ensure the correctness, robustness, security, availability, etc. As the changes take place so that the system conforms to its architecture and remains in conformance throughout its lifetime
Armando, François. "QoS coopérative pour l'adaptabilité des protocoles de Transport dans le contexte des activités de groupe". Phd thesis, INSA de Toulouse, 2010. http://tel.archives-ouvertes.fr/tel-00462528.
Pełny tekst źródłaMakarem, Nabil. "Performance evaluation and improvement of congestion control of the constrained application protocol for the Internet-of-things". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS289.
Pełny tekst źródłaThe Constrained Application Protocol (CoAP) is a lightweight core protocol designed by the Internet Engineering Task Force (IETF) used for communication between devices in the Internet of Things (IoT). In this research work, we propose new exact mathematical models to analyze the performance of CoAP in lossy IoT networks. This study provides insights about improving CoAP congestion control in such networks and highlights the properties -- including the limitations -- of CoAP. Besides, we show that the simple control mechanism reduces significantly CoAP performance especially in terms of bandwidth utilization since it prevents the protocol from acting efficiently during congestion periods. We then propose new improvements in order to enhance the trade-off between reliability and goodput while keeping the algorithms reasonably simple for constrained devices. First, we optimize further the estimation procedure of the retransmission timeout in order to enhance congestion detection. Timeouts are the only indicator used in CoAP to detect losses, and losses are used as a strong indicator to detect congestion. Second, we replace the backoff algorithm by "real" congestion control algorithms inspired from the well-known Additive Increase Multiplicative Decrease technique and a recent measurement-based congestion control called BBR. Our analysis using both our simulator and Contiki/Cooja environment show that the rate-based approach outperforms the backoff-based approach. Moreover, all the results show that our algorithms achieve a much better tradeoff between goodput, reliability and overhead
Slimani, Hicham. "Protocoles coopératifs pour réseaux sans fil". Phd thesis, Toulouse, INPT, 2013. http://oatao.univ-toulouse.fr/10309/1/slimani.pdf.
Pełny tekst źródłaDuong, Le Minh. "Metric-based Rate Control for Transport Protocols in Multi-hop Wireless Networks". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00726025.
Pełny tekst źródłaTarek, mohamed ibrahim hafez Dina. "Development of Spectrum Sharing Protocol for Cognitive Radio Internet of Things". Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0280.
Pełny tekst źródłaInternet of Things (IoT) presents a new life style by developing smart homes, smart grids, smart city, smart transportation, etc., so IoT is developing rapidly. However recent researches focus on developing the IoT applications disregarding the IoT spectrum scarcity problem facing it. Integrating Internet of Things (IoT) technology and Cognitive Radio Networks (CRNs), forming Cognitive Radio Internet of Things (CRIoTs), is an economical solution for overcoming the IoT spectrum scarcity. The aim of this thesis is to solve the problem of spectrum sharing for CRIoT; the work in thesis is presented in three parts, each represents a contribution. Our first contribution is to propose two new protocols to solve the problem of channel status prediction for interweave CRNs. Both protocols use Hidden Markov Model (HMM). In the training stage of both protocols, the available data are trained to produce two HMM models, an idle HMM model and a busy one. Both models are used together to produce the 2-model HMM. In the prediction stage the first protocol uses Bayes theorem and the 2-model HMM, while the second protocol uses Support Vector Machine (SVM) employing the parameters produced from applying the 2-model HMM, named 2-model HMM-SVM. The 2-model HMM-SVM outperforms the classical HMM and 2-model HMM in terms of the true percentage, the inaccuracy and the probability of primary users’ collision (false negative prediction). In our second contribution, we proposed a centralized time slotted packet scheduling protocol for CRIoTs. It uses Discrete Permutation Particle Swarm Optimization (DP-PSO) for scheduling the IoT device packets among the free slots obtained from applying cognitive radio networks' channel estimation technique proposed in the first part. Our proposed protocol is applied to smart healthcare facility. Configuring three main building blocks for the used application architecture; the IoT devices block, the first layer fog nodes block and the central fog server. Each group of IoT devices is connected to a fog node, the entire fog nodes in the system are connected to the central fog node. The proposed protocol is named Scheduling based-on Discrete Permutation Particle Swarm Optimization (SDP-PSO). An objective fitness function is formulated with three parameters; maximizing the fairness index among fog nodes, minimizing the packets' queuing delay and minimizing the number of dropped packets that exceeded their allowed time in the network without being sent. The performance of the proposed SDP-PSO protocol overcomes an old protocol named spectrum auction in terms of the fairness between fog nodes, the average queuing delay, the number of dropped packets and the time and the space complexity. Finally, in the third contribution, we proposed a distributed packets' scheduling protocol for CRIoTs. Our proposed protocol can be applied to an urban traffic control. The configured system in this part consists of three main building blocks; the IoT devices block, the first fog layer block (Road Side Units (RSUs)) and the second fog layer block. Each group of IoT devices is connected to a RSU, each group of RSU are connected to a fog node which acts as their cluster head. The fog nodes are connected together forming a partial mesh network. The proposed distributed packets' scheduling protocol for CRIoTs is applying three distributed access strategies together with the SDP-PSO proposed in the second part to schedule the packets on the estimated free slots resulted from applying the protocol proposed in the first part. The used access strategies are the classical round robin, in addition to two proposed ones named; the vertex cover and the enhanced round robin. An objective fitness function near similar to that used in the centralized protocol, was applied but with some differences to make it suitable for distributed scheduling
Loeuillet, Jean-Louis. "Implémentation d'un protocole de niveau réseau sur un réseau local de type GIXINET". Paris 11, 1987. http://www.theses.fr/1987PA112360.
Pełny tekst źródłaHassan, Khaldon. "Architecture De Contrôleur Mémoire Configurable et Continuité de Service Pour l'Accès à la Mémoire Externe Dans Les Systèmes Multiprocesseurs Intégrés à Base de Réseaux Sur Puce". Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00656470.
Pełny tekst źródłaBekono, Nina Pelagie. "Impact du changement du protocole de routage dans un réseau". Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC058/document.
Pełny tekst źródłaRouting protocols in networks may change for many reasons: detection of a particular event, planned or unplanned change of topology, mobility of nodes, version obsolescence, etc. As these changes can not be simultaneously detected or taken into account by all nodes of the network, it is necessary to consider the case where some nodes use the initial routing protocol, while others have migrated to the new routing protocol. The work of this thesis deals with the problem of routing loops that may appear in this context, and which considerably degrade the performance of the network. We propose node scheduling solutions to control migration to avoid these loops. First, we consider the context of static networks and centralized protocols with the particular case of changing metrics. We propose two centralized avoidance solutions: SCH-m (minor improvement of an existing heuristic), and ACH (new contribution), based on the identification of the routing loops in the strongly connected components contained in the union of the two routing protocols. We accelerate the migration of the network by a step-by-step merge operation of the different transitions produced. Second, we evolve towards the distributed protocols while preserving the static context of the network, and consider the particular case of the withdrawal or breakdown of a node. We also propose two solutions: RTH-d (minor improvement of an existing heuristic) and DLF (new contribution for loops of size 2) based on message exchange of nodes for both failure detection and for migration notification. Thirdly, we consider the context of nodes mobility, and study the performance of DLF- k (improved version of DLF which takes into account loops of size less than or equal to k, with k >= 2) on two types of applications: applications with a single mobile node that is the destination, and applications with a group of mobile nodes
Makké, Rani. "Qualité de Service et Performances des Protocoles de Transport dans l'UTRAN". Phd thesis, Télécom ParisTech, 2003. http://tel.archives-ouvertes.fr/tel-00005734.
Pełny tekst źródłaL'AAL2 constitue un véritable protocole de transport qui se superpose au protocole de transport ATM. Or, dans les normes de l'AAL2, aucune notion de qualité de service (QoS) n'était définie pendant notre étude. En plus, les études faites étaient insuffisantes pour définir un modèle complet de la QoS dans l'AAL2. Nous avons alors contribué pour définir des classes de QoS au niveau AAL2, des paramètres de QoS, des capacités de transfert (AAL2-TC) ainsi que des critères de performance. Ensuite, nous proposons des schémas d'association (mapping) entre les différentes classes de service de l'UMTS et les classes de l'AAL2 d'une part et entre les classes de l'AAL2 et les classes de l'ATM d'autre part. Un schéma de partage de la bande passante entre les différentes classes est proposé ainsi qu'un schéma de contrôle d'admission des connexions AAL2. Dans le cas où plusieurs types de trafic seraient agrégés dans le même VC ATM, un mécanisme d'ordonnancement au niveau AAL2 est nécessaire pour pouvoir différencier entre les classes de services. Plusieurs algorithmes d'ordonnancement sont proposés au niveau de l'AAL2 et une comparaison entre ces mécanismes est réalisée dans plusieurs contextes pour évaluer les avantages et les inconvénients de chaque algorithme. Nous proposons un nouvel algorithme dynamique appelé DyWRR qui s'adapte avec le changement du trafic. Nous étudions aussi un paramètre important relatif au protocole AAL2 qui est le Timer-CU (Timer - Combined Use). Ce paramètre de temporisation a une influence sur le délai des paquets et sur le taux d'utilisation de la bande passante. Une étude fine et détaillée de ce paramètre est réalisée pour obtenir des résultats sur sa valeur optimale. Le choix de l'ATC (ATM Transfer Capability) pour le transport des connexions AAL2 fait une partie de notre étude. Le DBR et le SBR sont deux ATC proposées et une comparaison entre ces deux solutions est analysée. Quand on parle de l'AAL2 comme un protocole de transport, l'idée de la commutation AAL2 ne sera plus exclue. Au lieu de commuter les cellules ATM, on peut commuter les paquets AAL2 pour qu'on puisse séparer les connexions AAL2 dans un nud donné du réseau. La commutation AAL2 présente des avantages mais également des inconvénients que nous traitons dans cette thèse.
Les résultats de létude sur lAAL2 faite dans le cadre de cette thèse ont été utilisés pour une contribution à la normalisation au sein de lITU-T (International Telecommunication Union -Telecommunication standardization sector). Ces travaux de normalisation ont abouti à une nouvelle norme appelée ITU-T I.378 qui traite la problématique de la qualité de service et du contrôle de trafic au niveau de lAAL2.
Dans la Release 5 du 3GPP, l'IP est introduit comme protocole de transport sur les interfaces Iub et Iur dans une optique de réaliser des réseaux "tout-IP". Ce protocole, dans sa version simple, ne peut pas garantir une qualité de service parce qu'il ne fournit qu'une seule classe de service pour tous les flux, la classe du meilleur effort (Best Effort). Des mécanismes de différenciation des services sont alors nécessaires comme DiffServ ou IntServ dans le contexte de l'UTRAN. Plusieurs architectures pour le transport en IP sur l'interface Iub sont présentées. D'ailleurs, ces solutions en IP introduisent une charge supplémentaire à cause de la longueur des en-têtes. Sachant que les opérateurs des télécommunications s'intéressent à l'optimisation de la bande passante sur les liens appelés Last Mile Link, une étude est alors réalisée dans cette thèse pour évaluer les performances des solutions en IP dans l'UTRAN.
Nguyen, Xuan hung. "Réseaux de communication et applications de contrôle-commande". Thesis, Toulouse, INSA, 2011. http://www.theses.fr/2011ISAT0025/document.
Pełny tekst źródłaThis thesis is in the field of Networked Controlled Systems, which are multidisciplinary systemsand which experience a great development in the context of the current technology andintroduce new research problems, particularly for the communities of Automatic Control andCommunication Network. The aim is to show the interest in considering a bidirectional link betweenthe Quality of Control (QoC) (stability and performance of process control applications) andQuality of Service (QoS) (delays in the transmissions) and to focus on Local Area Networks and,more particularly, on the scheduling of frames in the MAC layer in which we consider CSMAMAC protocols.Our work first concerns a CAN network where we have three proposals. The first proposalconsists of solutions for QoS, for process control applications, which are based on the conceptof hybrid priority for the frame scheduling in which we define a dynamic priority part which dependson a QoC parameter. This allows to implement a relation QoC→QoS. The second proposalconsists of QoC solutions by using a compensation method for time delays (maintenance of dominantpoles) which allows to implement a relation QoS→QoC. The third proposal consists inimplementing a relation QoS⇋QoC that ensures, for the implementation of several applications,a fairness property. We then discuss the specific context of Wireless LANs, where, on the onehand, we define collision-free CSMA MAC protocols on the basis of priorities and, on the otherhand, we show the feasibility of the ideas developed in the CAN network