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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Network Traffic Regulator for Diagnostic Messages in Modular Product / Reglering av nätverkstrafik för diagnoskommunikation i en modulär produkt

Thakrar, Nikhil January 2017 (has links)
The aim of this thesis project is to explore a network traffic regulator using bandwidth management techniques that regulates data traffic with the objective to use the network bandwidth to its maximum capacity while ensuring that the network is not overloaded. The bandwidth in the existing network architecture is shared between two co-existing, distinct data flows for on-board communication and diagnostic communication in an in-vehicle network. The diagnostic communication must not interfere with the more critical on-board communication and it should comply with the remaining bandwidth. In the existing solution, fixed delays are imposed on the data traffic which result in a waste of network capacity. The approach presented in this thesis uses two regulation algorithms for different types of diagnostic services. One regulation algorithm is activated for diagnostic services that require data segmentation and multiple data frames to accommodate the transferred data. This algorithm makes use of the Flow Control parameter Separation Time specified in ISO 15765-1:2011 "Road vehicles -- Diagnostic communication over Controller Area Network (DoCAN)". The other algorithm regulates diagnostic services that generate bursts of single frames where data segmentation is not required and it does so using traffic shaping techniques. The results in this thesis show that the network traffic indeed can be regulated for different diagnostic services by using the two mentioned regulation algorithms. The results also show that data is not lost due to high network utilisation and that the bandwidth is used to its maximum capacity without having to impose fixed delays on the network system. The regulator is adaptive in the sense that it can be used for different vehicle configurations with compatible network systems to ensure quality of service and a robust network system. / I detta examensarbete är målet att utforska en metod för att reglera  nätverkstrafik genom att använda tekniker inom bandbreddshantering  med syfte att utnyttja bandbredden till dess maximala kapacitet utan att överbelasta nätverket. Bandbredden i den nuvarande nätverksarkitekturen delas mellan två dataflöden för onboard kommunikation och diagnostisk kommunikation. Den diagnostiska kommunikationen får inte på någotvis störa onboard kommunkationen och får anpassa sig till den bandbredd som kvarstår. I det existerande systemet införs fixa fördröjningar i nätverkstrafiken vilket medför ett onödigt slöseri på nätverkskapaciteten och som också medför att de diagnostiska tjänsterna tar längre tid att utföra.  Tillvägagångssättet som presenteras i detta arbete använder två regleringsalgoritmer för olika typer av diagnostiska tjänster. En algoritm används för tjänster som kräver datasegmentering och flera dataramar för att skicka data. Den här algoritmen använder parametern Separation Time som är specificerad i ISO standarden 15765-1:2011 "Road vehicles -- Diagnostic communication over Controller Area Network (DoCAN)". Diagnostiska tjänster som istället genererar en skur av enstaka dataramar regleras med en traffic shaping algoritm som heter Token Bucket. Resultaten i detta arbete visar att det går att reglera nätverkstrafiken för olika typer av diagnostiska tjänster genom att använda de två utvecklade algoritmerna. Resultaten visar också att data inte går förlorat vid höga nätverkslaster och att bandbredden används maximalt utan att behöva införa fixa fördröjningar i nätverkssystemet. Regleraren är adaptiv i bemärkelsen att den kan användas för alla tänkbara fordonskonfigurationer med kompatibelt nätverkssystem för att försäkra quality of service och robusthet.
72

Sistemas de comunicação CAN FD: modelamento por software e análise temporal. / CAN FD communication systems: modeling software and temporal analysis.

Andrade, Ricardo de 26 September 2014 (has links)
O CAN (Controller Area Network) é um padrão no barramento de comunicação, amplamente difundido em aplicações industriais, particularmente em sistemas automotivos. Atualmente, um dos principais problemas no ramo automotivo é que esse barramento está com muitas mensagens no barramento, resultado da incorporação incremental de sistemas eletrônicos em automóveis, visto que há uma exigência maior de conectividade devido às exigências da sociedade e mercado. Como alternativa, vem sendo desenvolvida uma nova rede de comunicação, conhecida como CAN with Flexible Data-Rate (CAN-FD), que é um barramento com velocidade de transmissão de informação mais alta e maior capacidade de transporte de dados. Este projeto tem por objetivo principal explorar as funcionalidades da rede CAN-FD, através de simulações do trânsito de mensagens numa rede CAN-FD usando os dados de uma rede real CAN, e verificando a previsibilidade de ambas no âmbito de um protocolo que possa atender à demanda de sistemas complexos. A comparação é executada a partir de um conjunto de mensagens adicionadas na rede, para verificar os limites de transmissão de cada uma das redes, e os respectivos tempos de atraso das mensagens. Como um segundo estudo de caso, uma rede de controle em malha fechada foi desenvolvida, conectada a um barramento CAN e um barramento CAN-FD. Essa técnica de controle permitiu eliminar os ruídos que interferem no controle, e checar o limite em que o protocolo de comunicação consegue manter em uma malha de controle funcionando. Os resultados mostraram que é possível transmitir uma imensa quantidade de dados com o menor uso do busload (quantidade de mensagens transmitidas) no veículo através do uso do barramento CAN-FD, porém ainda não foi lançado no mercado um controlador do CAN-FD para realizar essa tarefa. Por outro lado, os dois protocolos, CAN-FD e CAN, tem suas previsibilidades comprometidas pois não conseguem enviar a mensagem quando o barramento está superior a 98,86% de carga. / The CAN (Controller Area Network) is a standard in the communication bus, widespread in industrial applications, particularly in automotive systems. Currently, one of the main problems in the automotive industry is that this bus is with many messages on the bus, the result of incremental incorporation of electronic systems in automobiles, since there is a greater demand for connectivity due to the demands of society and the market. Alternatively, it has been developed a new communications network, known as CAN with Flexible Data-Rate (CAN-FD), which is a bus with transmission speeds higher and higher capacity data transport information. This project\'s main objective is to explore the features of the network CAN-FD, through simulations of the traffic of messages on a CAN network FD using data from a real CAN network, and verifying the predictability both in the context of a protocol that can meet the demand complex systems. The comparison is performed from a set of messages added to the network to verify the boundaries of each of the transmission networks and the respective delay times of the messages. As a second case study, a network of closed-loop control was developed, connected to a CAN bus and CAN bus FD. This control technique has eliminated the noises that interfere with the control and check the extent that the communication protocol can keep a control loop running. The results showed that it is possible to transmit a huge amount of data with the lowest usage busload (amount of transmitted messages) to the vehicle through the use of CAN bus FD, but not yet released to market a CAN controller FD to accomplish this task . Moreover, both protocols, CAN-FD and CAN has its predictability compromised because they are unable to send the message when the bus is more than 98.86% load.
73

Sistemas de comunicação CAN FD: modelamento por software e análise temporal. / CAN FD communication systems: modeling software and temporal analysis.

Ricardo de Andrade 26 September 2014 (has links)
O CAN (Controller Area Network) é um padrão no barramento de comunicação, amplamente difundido em aplicações industriais, particularmente em sistemas automotivos. Atualmente, um dos principais problemas no ramo automotivo é que esse barramento está com muitas mensagens no barramento, resultado da incorporação incremental de sistemas eletrônicos em automóveis, visto que há uma exigência maior de conectividade devido às exigências da sociedade e mercado. Como alternativa, vem sendo desenvolvida uma nova rede de comunicação, conhecida como CAN with Flexible Data-Rate (CAN-FD), que é um barramento com velocidade de transmissão de informação mais alta e maior capacidade de transporte de dados. Este projeto tem por objetivo principal explorar as funcionalidades da rede CAN-FD, através de simulações do trânsito de mensagens numa rede CAN-FD usando os dados de uma rede real CAN, e verificando a previsibilidade de ambas no âmbito de um protocolo que possa atender à demanda de sistemas complexos. A comparação é executada a partir de um conjunto de mensagens adicionadas na rede, para verificar os limites de transmissão de cada uma das redes, e os respectivos tempos de atraso das mensagens. Como um segundo estudo de caso, uma rede de controle em malha fechada foi desenvolvida, conectada a um barramento CAN e um barramento CAN-FD. Essa técnica de controle permitiu eliminar os ruídos que interferem no controle, e checar o limite em que o protocolo de comunicação consegue manter em uma malha de controle funcionando. Os resultados mostraram que é possível transmitir uma imensa quantidade de dados com o menor uso do busload (quantidade de mensagens transmitidas) no veículo através do uso do barramento CAN-FD, porém ainda não foi lançado no mercado um controlador do CAN-FD para realizar essa tarefa. Por outro lado, os dois protocolos, CAN-FD e CAN, tem suas previsibilidades comprometidas pois não conseguem enviar a mensagem quando o barramento está superior a 98,86% de carga. / The CAN (Controller Area Network) is a standard in the communication bus, widespread in industrial applications, particularly in automotive systems. Currently, one of the main problems in the automotive industry is that this bus is with many messages on the bus, the result of incremental incorporation of electronic systems in automobiles, since there is a greater demand for connectivity due to the demands of society and the market. Alternatively, it has been developed a new communications network, known as CAN with Flexible Data-Rate (CAN-FD), which is a bus with transmission speeds higher and higher capacity data transport information. This project\'s main objective is to explore the features of the network CAN-FD, through simulations of the traffic of messages on a CAN network FD using data from a real CAN network, and verifying the predictability both in the context of a protocol that can meet the demand complex systems. The comparison is performed from a set of messages added to the network to verify the boundaries of each of the transmission networks and the respective delay times of the messages. As a second case study, a network of closed-loop control was developed, connected to a CAN bus and CAN bus FD. This control technique has eliminated the noises that interfere with the control and check the extent that the communication protocol can keep a control loop running. The results showed that it is possible to transmit a huge amount of data with the lowest usage busload (amount of transmitted messages) to the vehicle through the use of CAN bus FD, but not yet released to market a CAN controller FD to accomplish this task . Moreover, both protocols, CAN-FD and CAN has its predictability compromised because they are unable to send the message when the bus is more than 98.86% load.
74

Řízení samoobslužných dveří a vzduchového pérování městského autobusu pomocí sběrnice CAN / Control of Passenger Operated Doors and Air Springs of Town Bus by means ofCAN-bus

Sláma, Michal January 2009 (has links)
The Diploma thesis is divided into 2 parts. The first one deals with the description of CAN-bus and the protocol of SAE J1939. The second part contains the practical solution to controlling of Passenger Operated Doors and controlling of Air Sprinte (ECAS). Both parts refer to contemporary (conventions/standards) and the whole task is solved in a new program environment KIBES-32.
75

Combining Anomaly- and Signaturebased Algorithms for IntrusionDetection in CAN-bus : A suggested approach for building precise and adaptiveintrusion detection systems to controller area networks

Andersson, Robin January 2021 (has links)
With the digitalization and the ever more computerization of personal vehicles, new attack surfaces are introduced, challenging the security of the in-vehicle network. There is never such a thing as fully securing any computer system, nor learning all the methods of attack in order to prevent a break-in into a system. Instead, with sophisticated methods, we can focus on detecting and preventing attacks from being performed inside a system. The current state of the art of such methods, named intrusion detection systems (IDS), is divided into two main approaches. One approach makes its models very confident of detecting malicious activity, however only on activities that has been previously learned by this model. The second approach is very good at constructing models for detecting any type of malicious activity, even if never studied by the model before, but with less confidence. In this thesis, a new approach is suggested with a redesigned architecture for an intrusion detection system called Multi-mixed IDS. Where we take a middle ground between the two standardized approaches, trying to find a combination of both sides strengths and eliminating its weaknesses. This thesis aims to deliver a proof of concept for a new approach in the current state of the art in the CAN-bus security research field. This thesis also brings up some background knowledge about CAN and intrusion detection systems, discussing their strengths and weaknesses in further detail. Additionally, a brief overview from a handpick of research contributions from the field are discussed. Further, a simple architecture is suggested, three individual detection models are trained and combined to be tested against a CAN-bus dataset. Finally, the results are examined and evaluated. The results from the suggested approach shows somewhat poor results compared to other suggested algorithms within the field. However, it also shows some good potential, if better decision methods between the individual algorithms that constructs the model can be found.

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