Dissertations / Theses: 'Communication protocols and bus'

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McDonnell, Craig. "Adjustable speed drive integration via Fieldbus." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268162.

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Link, Jeffrey P. "Design of a serial communication protocol and bus interface chip for tactile communications." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA362194.

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Thesis (M.S. in Electrical Engineering) Naval Postgraduate School, March 1999.
Thesis advisor(s): Douglas J. Fouts. "March 1999". Includes bibliographical references (p. 285). Also available online.

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Wolfram, Ted. "Bridging two CAN-bus segments using radio communication with the IEEE 802.15.4 protocol." Thesis, Jönköping University, JTH, Computer and Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-622.

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This thesis will investigate the possibilities to wireless communicate within time critical applications with the radio protocol IEEE 802.15.4.

IEEE 802.15.4 is a very quick protocol so the delays and jitter can be ignored in a small network.

The thesis handles the question: Is it possible to split a CAN-bus and send the data via radio to the other side of the CAN-bus?

The big problems with this are:

• Will it be treated like a transparent link and not disturb the original functionality?

• How does a system which is split up by radio treat new nodes on the bus?

• What will be the maximum speed and the maximum utilization factor for the split up bus?

• What new suitable protocols can be implemented on a higher level to get the split bus to work?

This is modeled and discussed, real measurement from a radio link is used in the model to see if it’s possible.

The radio communication will satisfy the demands from the company regarding their application. With an efficient error handling and a smart transmission protocol the application can be a very smart way of sending CAN-data via radio.

Denna rapport undersöker möjligheterna med att kommunicera trådlöst i

tidskritiska applikationer med hjälp av radioprotokollet IEEE 802.15.4.

IEEE 802.15.4 är ett väldigt snabbt protokoll så jitter och fördröjningen i sändningarna kan försummas för så små nätverk som tas upp i denna uppsats.

Går det att bryta en CAN-buss och koppla in denna radiolänk så att den

uppfattas som transparent?

Många problem kommer att dyka upp om detta görs, några av dem är dessa:

• Hur behandlar ett system nya noder som kopplas in om CAN-bussen är uppdelad?

• Vilken är den maximala hastigheten och utnyttjandefaktor som kan uppnås av den delade CAN-bussen?

• Måste ett överliggande protokoll användas för att sköta om datatrafiken mellan bussarna?

Detta modelleras och diskuteras efter det att de uppmätta mätvärdena har samlats in och analyserats.

Det som framkom var att det fungerar väldigt bra, data kommer fram i tid och felen i radiosändningarna är väldigt små. Med en väl genomtänkt felhantering och ett likaså genomtänkt omsändningsprotokoll kommer detta att fungera väldigt bra beroende på avstånd och antennval.

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Souza, Sthefany Fernandes de. "Viabilidade da implementação do protocolo IPMI em um SYSTEM-ON-CHIP /." Ilha Solteira, 2019. http://hdl.handle.net/11449/190946.

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Orientador: Aílton Akira Shinoda
Resumo: Bastidores eletrônicos de alta performance e disponibilidade utilizam o protocolo Intelligent Platform Management Interface (IPMI) para gerenciar seus dispositivos, controlando e monitorando os recursos disponíveis. Neste contexto para inserir dispositivos com tecnologia mais avançada, novos projetos foram elaborados para atualização dos sistemas de hardware e software baseados em System-on-Chip (SoC), principalmente na área de Física de Alta Energia. Uma aplicação existente, desenvolvida na parceira São Paulo Research and Analysis Center – Fermi National Accelerator Laboratory (SPRACE–FERMILAB) na colaboração internacional do Compact Muon Solenoid detector/Large Hadron Collider/European Organization for Nuclear Research (CMS/LHC/CERN), utiliza o protocolo IPMI implementado em um microcontrolador, contudo, para o processo de atualização vigente, há um interesse desta implementação em SoC. Assim, esta pesquisa foi desenvolvida como o estudo da viabilidade da implementação IPMI em um SoC. Para estabelecer e verificar o protocolo IPMI via barramento I²C, a plataforma Xilinx ZC702 Evaluation Board foi utilizada com os respectivos dispositivos SoC Zynq e Erasable Programmable Memory (EEPROM). Além disso foi desenvolvido uma estrutura simples do IPMI no sistema operacional em tempo real (FreeRTOS) baseados em modelos de hardware e software criados na plataforma Xilinx IDE e SDK. Por meio dos resultados apresentados é possível constatar a viabilidade da implementação IPMI em sistema... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: High performance and availability electronic racks use the Intelligent Platform Management Interface (IPMI) protocol to manage your devices by controlling and monitoring available resources. In this context to insert devices with more advanced technology, new projects were elaborated to update the System-on-Chip (SoC) based hardware and software systems, mainly in the area of High Energy Physics. An existing application developed at the São Paulo Research and Analysis Center partner - Fermi National Accelerator Laboratory (SPRACE – FERMILAB) in the international collaboration of the Compact Muon Solenoid detector/Large Hadron Collider/European Organization for Nuclear Research (CMS/LHC/CERN) uses The IPMI protocol implemented in a microcontroller, however, for the current update process, there is an interest of this implementation in SoC. Thus, this research was developed as the study of the viability of implementing IPMI in a SoC. To establish and verify the IPMI protocol via I²C bus, the Xilinx ZC702 Evaluation Board platform was used with the respective SoC Zynq and Erasable Programmable Memory (EEPROM) devices. In addition, a simple IPMI framework in the real time operating system (FreeRTOS) based on hardware and software models created on the Xilinx IDE and SDK platform was developed. From the results presented, it is possible to verify the viability of IPMI implementation in systems such as SoC Zynq as platform management controller, which allows migration and further t... (Complete abstract click electronic access below)
Mestre

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Guimarães, Alexandre de Almeida. "Análise da norma ISO11783 e sua utilização na implementação do barramento do implemento de um monitor de semeadora." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-13082008-161944/.

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A utilização de eletrônica embarcada na agricultura tem crescido rapidamente, tornando necessária a utilização de diversos módulos a bordo da máquina (trator e implemento). Considerando-se os impactos relacionados a esta tendência, alternativas tecnológicas devem ser geradas e devidamente exploradas, especialmente sobre os sistemas de controle e o cabeamento requeridos. As arquiteturas eletro-eletrônicas devem garantir o mínimo de custo de implementação e tempo de manutenção. Os sistemas de controle devem operar maximizando a disponibilidade das informações, o que implica a necessidade de troca de dados entre estes diversos sistemas de controle e, portanto, a existência de um protocolo de comunicação serial internacionalmente padronizado. Neste contexto, este trabalho aborda os diversos protocolos de comunicação serial - como o RS232, o RS485 e o CAN (Controller Area Network) - e as suas normas específicas, voltadas às aplicações agrícolas, como a ISO11783 e a DIN 9684, comparando-as. Dessa análise resulta a indicação da ISO11783, norma baseada no protocolo CAN, como a mais interessante para as aplicações agrícolas. Essa norma é estudada em detalhes, o que permite a criação de um roteiro de estudo e implementação do referido protocolo. Finalmente, é desenvolvida uma aplicação deste protocolo, considerando-se uma rede de comunicação de dados de um Monitor de Semeadora, a fim de demonstrar sua aplicação prática.
The use of on-board electronics in agriculture has grown quickly, requiring many electronic modules on-board machines (tractor and implement). Considering the trend related impacts, alternative technologies should be developed and used properly, especially on control systems and on the required wiring harness. Electro-electronic architectures should provide minimum implementation cost and maintenance related time. Control systems should operate maximizing the availability of information that implies on the necessity of data exchange among these variety of control systems and also, on the existence of an international standardized serial communication protocol. Considering that, this documentation covers many serial communication protocols - as RS232, RS485 and CAN (Controller Area Network) - and the agricultural applications related standards as ISO11783 and DIN 9684, comparing them. This analysis results in the indication of ISO11783, a CAN Bus based standard, as the most interesting to agricultural applications. This standard is analyzed in details, making possible the development of a protocol related study and implementation guideline. Finally, a protocol related application is developed for a Planter Monitor implement bus network, looking forward to demonstrating an ISO11783 real implementation.

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Rehman, Habib Ur. "Designing and Development of a Data Logging and Monitoring Tool." Master's thesis, Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-212633.

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Since the mid 90's computer communication has become more and more common in cars and other auto mobiles. CAN based networks with sensors transmitting small data packets are utilized in the automotive industry to operate and supervise vehicles' functionality. To ease communication several higher layer protocols for CAN based networks have been developed. In some applications it is necessary to exchange information between networks using different protocols, and by connecting the two networks to a gateway, the information is translated and forwarded and intercommunication is enabled. This master thesis is conducted at Torqeedo GmbH, Munich. Theme of the thesis was “Designing and Development of a Data Logging and Monitoring Tool”. Term “data logging” refers to the gathering or collection of specific data over a period of time. Monitoring means evaluate the data we are logging. Tools for data logging and monitoring are used in variant application these days. In medical, in-vehicle data logging and environment monitoring. This data could be voltage, current temperature, Time stump, heartbeat of the patient, vehicle fuel level etc. To capture and log data various communication channels used. Such channel varies from simple data cable to satellite link. There are variant protocols used for different communication channels. For our DBHS logging and monitoring tool we are using CANopen protocol. Main goal of this thesis is to develop a tool which can make debugging easy and log connection box data so we can use logged data later on for offline data analysis and simulation purposes.

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Gautam, S. Vijay. "Performance Analysis Of A Variation Of The Distributed Queueing Access Protocol." Thesis, Indian Institute of Science, 1995. http://hdl.handle.net/2005/149.

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"A distributed queueing Medium Access Control (MAC) protocol is used in Distributed Queue Dual Bus (DQDB) networks. A modified version of the MAC protocol was proposed by R.R. Pillai and U. Mukherji in an attempt to overcome some of the shortcomings of the DQDB MAC protocol. They analyzed the performance of the system for Bernoulli arrivals and for large propagation delays between the nodes. We extend the performance analysis of the modified MAC protocol for a DQDB type of Network. The parameter of interest to us is the bus access delay. This has two components, viz., the request bus access delay and the data bu6 access delay. We use the model at the request point at node and present methods to evaluate the delay experienced in such a model. The model is an n-priority ./D/l queue with D vacations (non-preemptive priority) where n is the number of nodes sending requests on the request bus for transmission on the data bus. The methods presented help to evaluate the request bus access delay when the arrivals at each node are Markovian Arrival Processes (MAPs). The algorithms for evaluating the mean request bus access delay are based on matrix geometric techniques. Thus, one can use the algorithms developed in the literature to solve for the finite buffers case too. This model, for the request bus access delay, holds irrespective of the propagation delay between the nodes. We also evaluate the inter-departure time of class 1 customers and virtual customers in a 2-priority M/G/l system with G vacations (non-preemptive priority). In the case of Poisson arrivals at all the nodes, we would have a 2-priority M/D/l system with D vacations (non-preemptive priority). We thus evaluate the inter-arrival time of the free slots on the data bus as seen by Node 2. Note that this is independent of the number of active nodes in the network We then develop methods to evaluate the mean data bus access delay experienced by the customers at Node 2 in a three-node network with 2 nodes communicating with the third when the propagation delay between the nodes is large. We consider the case of finite Local Queue buffers at the two nodes. Using this assumption we arrive at process of arrivals to the Combined Queue and the process of free slots on the data bus to be Markov Modulated Bernoulli processes. The model at the combined queue at Node 2 then has a Quasi Birth-Death evolution. Thus, this system is solved by using the Ramaswami-Latouche algorithm. The stationary probabilities are then used to evaluate the mean data bus access delay experienced at Node 2. The finite buffer case of this system can be solved by G.Wi Stewart's algorithm. The method in modelling the system and the results are presented in detail for Poisson arrivals. The extension of this to more complex processes is also explained. We encounter in the analysis an explosion of the state-space of the system. We try to counter this by considering approximations to the process of free slots on the data bus. The approximations considered are on the basis of what are known as Idealized Aggregates. The performance of the approximation is also detailed. It works very well under low and moderate load but underestimates the mean delay under heavy load. Thereafter, we discuss the performance of the system with reference to the mean of the access delay and the standard deviation of the access delay under varying traffic at the two nodes. For this part we use simulation results to discuss the performance. The comparison between the performance measures at both the nodes is also done. Then we develop methods/techniques to understand the performance of the system when we have finite propagation delays between the nodes. We concentrate on the 3-node problem and calculate performance bounds based on linear programs. This is illustrated in detail for Bernoulli arrivals for the case of 1 slot propagation delay between the nodes as well as for the case of 2 slots propagation delay. The performance of the bounds obtained is also detailed. The presence of an idling system at the combined queue of Node 2 makes the bounds somewhat loose. Finally, we discuss the performance of the system with reference to the mean access delay and the standard deviation of the access delay under varying load on the system. Again, we rely on simulation studies. Finally, we study the performance of the system as a multiplexer. For this, we restrict the traffic to Markov Modulated Processes (or those which would satisfy the Gartner-Ellis Theorem requirements). The traffic is characterized by what are known as Envelope Processes - Lower and Upper. The class of processes which satisfy the conditions of the Gartner-Ellis theorem come under the category where both the Envelope Processes exist and the Minimum Envelope Rate and the Maximum Lower Envelope Rate are the same. We use the system evolution equations at the combined queue at any node to develop relations between the various input and output processes. First, this is done for a. system of this kind, in isolation. Then, we consider this system as a part of the modified protocol and present relations, among the various input and output processes, which are specific to the modified protocol. The possible use of all of the above to do Admission Control at the entry point to the Asynchronous Transfer Mode (ATM) network is also presented.

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Červinka, Radim. "Middleware pro framework Testos." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2021. http://www.nusl.cz/ntk/nusl-445506.

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Cílem této práce je vytvořit komunikační sběrnici pro platformu Testos, což umožní nástrojům platformy spolu komunikovat a využívat navzájem svoje služby. V textu jsou prozkoum8na současná řešení a protokoly založené na modelu Publish-Subscribe. Dále také práce specifikuje požadavky na komunikační sběrnici vyhovující potřebám platformy Testos a také navrhuje řešení pro splnění daných požadavků. V rámci výzkumu byly prozkoumány tři řešení - MQTT, DDS a AMQP. Průzkum každého řešení byl zaměřen na způsob komunikace a hlavní funkční prvky. Jako startovací bod implementace sběrnice byl vybrán protokol MQTT. Tato práce také specifikuje jak tento protokol rozšířit, aby byly splněny požadavky na sběrnici. Mezi stěžejní rozšíření navrhnuté v rámci této práce patří management životního cyklu požadavků rozšiřující způsob doručování zpráv a mechanismus zasílání požadavků standardu MQTT. Protokol byl také rozšířen o možnost shlukování zpráv do BULK paketu za účelem snížení množství potřebných síťových zdrojů. Výsledkem je Testos Bus, který je postavený na upraveném a rozšířeném protokolu MQTT, který zahrunuje implementaci brokeru a klientských knihoven pro Python a C++. Testos Bus naplňuje všechny povinné požadavky platformy, což ověřují automatické testy.

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Bojanovský, Tomáš. "Technika inteligentních budov." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230047.

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The thesis provides a basic concept of intelligent building and related fields where this technology is appropriate. The next section describes the systems used in this field, especially the so-called communication buses and protocols. For an overview of developments in this area there is also a list of major companies involved in this technology. As a practical example is then described by air temperature and air control facilities in the building A2 or A5 in a building located within the Faculty of Mechanical Engineering, Brno University of Technology. For both cases are also proposed possible treatment.

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Levek, Vladimír. "Nová hybridní jednovodičová sběrnice pro mikroelektronické systémy." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400417.

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The thesis is focused on the research and development of a new hybrid one-wire bus with special use enabling microelectronic integration. The bus, its physical layer and protocol have been developed based on applied research to meet the complex requirements of a new application group. These requirements are especially laid on the bus robustness and its immunity to interference and to work under real operating conditions. Part of the thesis is a description of existing solutions of one-wire buses, definition of current solutions and setting of goals for research of the new bus. Further are made the design of protocol and operating parameters of the bus operating in low power and power mode. In conclusion, the thesis deals with the practical verification of the proposed solution and there is also suggested a perspective of follow-up research in this area.

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Freitas, Paul Michael. "Feature-oriented specification of hardware bus protocols." Worcester, Mass. : Worcester Polytechnic Institute, 2008. https://www.wpi.edu/ETD-db/ETD-catalog/view_etd?URN=etd-042908-140922.

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Powell, Dave, and Paul Cook. "Community of Programming Protocols." International Foundation for Telemetering, 2009. http://hdl.handle.net/10150/606110.

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ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada
As new products are developed for the telemetry market, network interfaces are being used for set-up and control. This paper describes the programmability of various telemetry components that are now available and discusses the internal status functions that can be returned to the user or telemetry system via the same interface that are good indicators of system health. Possible control interfaces are discussed that could be used to interface many different components. Also discussed is the need for the Range Commanders Council to address the total programmability protocol issues related to connecting multiple components into a common setup and control bus.

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Kjellsson, Kenji. "Formal Methods in Verification of Interface and Bus Protocols." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177354.

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This master thesis is performed on behalf of the Swedish technology company Ericsson and is meant to evaluate the efficiency of an assertion-based Verification Intellectual Property (abVIP) against an already existing constrained random Verification Intellectual Property (crVIP). The abVIP is a verification entity which is connected with a predefined design and proves that the design is adhering to the specification properties through conditional checks, which uses mathematical proofs rather than prolonged simulation based input stimuli. A market research meant to cover the popularity of abVIPs within the EDA vendors has been conducted. This research showed that the focus of the commercially available VIPs are still on the traditional simulation based crVIP, as only a third of the contacted EDA vendors openly offered any commercial abVIPs for various protocols. These companies are Cadence Design System, Jasper Design Automation and Mentor Graphics. Based on the market research, the AXI 4 protocol has been chosen to be explored due to its popularity in formal based verification. The exploration phase answered questions related to how commercial abVIPs are built and what methods they considered. This was of particular interest as no industry standard methodology for formal based verification existed at time of writing. The companies for which the abVIPs were obtained from are referred to as company A and company B to avoid any confidentiality liability. Both abVIPs were assessed and shared many similarities although one was clearly more user friendly than the other. Finally, a custom abVIP have been developed during the course of this thesis for an Ericsson design which utilizes the serial Inter-IC (I2C) bus protocol. This abVIP verification performance is compared against already existing crVIP verification results. This phase showed that the development time of an abVIP is unchanged from that of a crVIP. The verification environment development time differed however in the favor of the abVIP. By not having to instantiate auxiliary modules, scoreboards or test cases, the abVIP was shown to gain weeks which were needed in the crVIP. For a significantly smaller subset of the crVIP verification set, the abVIP required more than twice the time needed for the crVIP to yield 100% assertion results. This indicates that protocols which rely on long chains of system clock operations results in large amount of states which the formal tool has to visit. For this reason, one verification run ended up in a state space so large the results did not converge. Thus it was concluded in this thesis that abVIPs are ultimately not a replacement of crVIPs but rather a complement and should be treated so by Ericsson as well. This is especially the case if the protocol to verify is a serial one.

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Wei, K.-K. "Modelling of communication protocols." Thesis, University of York, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373307.

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Nuggehalli, Pavan S. "Energy conscious communication protocols /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2003. http://wwwlib.umi.com/cr/ucsd/fullcit?p3091328.

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Bayol, Catherine. "Une approche structurelle et comportementale de modélisation pour la vérification de composants VLSI." Phd thesis, Université Joseph Fourier (Grenoble), 1995. http://tel.archives-ouvertes.fr/tel-00005027.

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Le mémoire décrit une méthode de modélisation et de validation de composants micro-programmes pour l'implantation de protocole de communication de réseaux. Cette mèthode a été développée dans le cadre de la conception du composant FICOMP qui met en oeuvre la norme de bus de terrain FIELDBUS. Le premier chapitre décrit le contexte industriel du projet FICOMP, les différents niveaux de spécification du composant et les outils de simulation et de vérification utilisés. Le chapitre deux présente le langage VOVHDL, une extension de VHDL pour la spécification des communications et des synchronisations entre processus concurrents, et en donne une sémantique synchrone en termes de systèmes à transitions étiquetées. Le chapitre trois présente une approche de modélisation pour les descriptions VOVHDL hiérarchiques, et en illustre l'application au composant FICOMP : les modules internes sont reliés à un module de communication pour former un module de niveau supérieur ; ce module est alors traduisible dans le format d'entrée de l'outil de vérification ASA+. Le chapitre quatre rappelle les primitives essentielles du langage VHDL, et formalise la sémantique de simulation de ce langage en termes de systèmes à transitions étiquetées. Les annexes détaillent l'application de la méthode, par la spécification et la traduction dans le modèle propose de deux modules du projet FICOMP

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Christensen, Peter Hugh. "Specification of Mil-Standard 1553 bus protocol and application to EA-6B communications countermeasures." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/27280.

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Curty, Alonso Marcos. "Cryptographic protocols in optical communication." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979048621.

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Lu, Ching-sung. "Automated validation of communication protocols /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu148726702499786.

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Haqqani, Mujeeb. "Fast prototyping of communication protocols." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5718.

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In this thesis we present a methodology and a life-cycle system for rapid implementation of communication protocols. Our proposed approach includes a scheme for automated coding and decoding of protocol (single module) formal specifications in Estelle into (and from) a KnowledgeBase(KB). An interactive experimental system, FPCP (Fast Prototyping of Communication Protocols), is designed and implemented. It automatically generates an interrogatable KnowledgeBase representation of the specification, and automatically generates an executable prototype of communication software corresponding to the formal (single module, normalized) specifications in ESTELLE format. Our approach allows developers to maintain single, useful and authoritative "reference specifications" throughout the protocol development life cycle. The automated encoding of the specifications into a rule based KB allows users to take advantage of rule based system features (Mackert) and yet maintain the Estelle specifications as the single authoritative reference specifications. (Abstract shortened by UMI.)

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Wickman, Tomas. "Evaluation of communication protocols between vehicle and server : Evaluation of data transmission overhead by communication protocols." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189228.

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This thesis project has studied a number of protocols that could be used to communicate between a vehicle and a remote server in the context of Scania’s connected services. While there are many factors that are of interest to Scania (such as response time, transmission speed, and amount of data overhead for each message), this thesis will evaluate each protocol in terms of how much data overhead is introduced and how packet loss affects this overhead. The thesis begins by giving an overview of how a number of alternative protocols work and what they offer with regards to Scania’s needs. Next these protocols are compared based on previous studies and each protocol’s specifications to determine which protocol would be the best choice for realizing Scania’s connected services. Finally, a test framework was set up using a virtual environment to simulate different networking conditions. Each of the candidate protocols were deployed in this environment and setup to send sample data. The behaviour of each protocol during these tests served as the basis for the analysis of all of these protocols. The thesis draws the conclusion that to reduce the data transmission overhead between vehicles and Scania’s servers the most suitable protocol is the UDP based MQTT SN.
I den här rapporten har jag undersökt ett antal protokoll som kan användas för att kommunicera mellan server och lastbil och därmed användas för Scanias Connected Services. Då det är många faktorer som är intressanta när det kommer till kommunikation mellan lastbil och server för Scania som till exempel responstid, överföringshastighet och mängden extra data vid överföring så har jag valt att begränsa mig till att utvärdera protokollen utifrån hur mycket extra data de använder vid överföring och hur detta påverkas av paketförlust. Rapporten börjar med att ge en överblick över vilka tänkbara protokoll som kan användas och vad de kan erbjuda gällande Scanias behov. Efter det så jämförs protokollen baserat på tidigare studier och protokollens specifikationer för att avgöra vilket protokoll som är bäst lämpat att användas i Scanias Connected Services. Sists så skapas ett virtuellt ramverk för att simulera olike nätverksförhållanden. Här testas varje protokoll och får sända olike datamängder för att sedan få sin prestanda utvärderad baserat på hur mycket extra data som sändes. Dessa resultat ligger sedan till grund för den analys och slutsats angående vilket protokoll som är bäst lämpat att användas av Scania. Rapporten drar slutsatsen att baserat på den information som finns tillgänglig och de resultat som ficks av testerna så skulle den UDP baserade MQTT-SN vara bäst lämpad för att minimera mängden extra data som skickas.

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Gomes, Rui Miguel Soares. "Intelligent peripherals with digital communication bus." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/5563.

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Mestrado em Engenharia Electrónica e Telecomunicações
Esta dissertação é parte integral do projecto ECU2010 e é focada no desenvolvimento de Periféricos Inteligentes que são conectados à ECU através de um Barramento Digital de Comunicação. O projecto ECU2010 está centrado no desenvolvimento de uma nova arquitectura da unidade de controlo electrónico (ECU) para desporto automóvel, focada no controlo de motores de combustão interna. A arquitectura proposta deverá ser ter a capacidade de controlar um motor de combustão interna usando os mais modernos modelos de controlo, mas sendo baseada numa modelo de processamento distribuído, composta por módulos de processamento auto-suficientes ao nível de comunicações e armazenamento e de sensores/actuadores com inteligência capazes de processamento prévio de dados. A ênfase desta dissertação será colocada apenas nos Periféricos Inteligentes e no Barramento Digital de Comunicação. Este documento irá analisar e propor uma solução para a inclusão de capacidades de processamento, armazenamento e diagnóstico nos periféricos, assim como o desenvolvimento de um Barramento Digital de Comunicação que permite aos periféricos comunicarem com a ECU e sincronizarem-se com a rotação do motor.
This dissertation is an integral part of the ECU2010 project and is focused on the development of Intelligent Peripherals which connect to the ECU by means of a Digital Communication Bus. The ECU2010 project is centered on developing a new architecture of electronic control units (ECU) for motor sport, focussing on control of internal combustion engines. The proposed new architecture should be capable of controlling an internal combustion engine using the state-of-the art control models, but based on a distributed processing model consisting on self-sufficient processing modules in terms of communications, storage and intelligent enabled sensors/actuators, which is able to produce low-level data processing. The focus of this dissertation will only be the Intelligent Peripherals and the Digital Communication Bus. This document will analyse and propose a solution for the incorporation of processing, storage and diagnostic capabilities into peripherals, as well as the development of a Digital Communication Bus which allows the peripherals to communicate with the ECU and synchronize them with the engine’s rotation.
FCT; FSE

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23

Aarts, Fides. "Inference and Abstraction of Communication Protocols." Thesis, Uppsala University, Department of Information Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111249.

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In this master thesis we investigate to infer models of standard communication protocols using automata learning techniques. One obstacle is that automata learning has been developed for machines with relatively small alphabets and a moderate number of states, whereas communication protocols usually have huge (practically infinite) sets of messages and sets of states. We propose to overcome this obstacle by defining an abstraction mapping, which reduces the alphabets and sets of states to finite sets of manageable size. We use an existing implementation of the L* algorithm for automata learning to generate abstract finite-state models, which are then reduced in size and converted to concrete models of the tested communication protocol by reversing the abstraction mapping.

We have applied our abstraction technique by connecting the Learn-Lib library for regular inference with the protocol simulator ns-2, which provides implementations of standard protocols. By using additional reductionsteps, we succeeded in generating readable and understandable models of the SIP protocol.

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24

Chen, Nanxing. "Passive interoperability testing for communication protocols." Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00869819.

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In the field of networking, testing of communication protocols is an important activity to validate protocol applications before commercialisation. Generally, the services that must be provided by a protocol are described in its specification(s). A specification is generally a standard defined by standards bodies such as ISO (International Standards Organization), IETF (Internet Engineering Task Force), ITU (International Telecommunication Union), etc. The purpose of testing is to verify that the protocol implementations work correctly and guarantee the quality of the services in order to meet customers expectations. To achieve this goal, a variety of testing methods have been developed. Among them, interoperability testing is to verify that several network components cooperate correctly and provide expected services. Conformance testing verifies that a product conforms to its specification. Robustness testing determines the degree to which a system operates correctly in the presence of exceptional inputs or stressful environmental conditions. In this thesis, we focus on interoperability testing. The general architecture of interoperability testing involves a system under test (SUT), which consists of at least two implementations under test (IUT). The objectives of interoperability testing are to ensure that interconnected protocol implementations are able to interact correctly and, during their interaction, provide the services predefined in their specifications. In general, the methods of interoperability testing can be classified into two approaches: active and passive testing. Among them, active test is the most conventionally used technique, which aims to test the implementations (IUT) by injecting a series of test messages (stimuli) and observing the corresponding outputs. However, the intrusive nature of active testing is that the tester has the ability to control IUTS. This implies that the tester interrupts inevitably the normal operations of the system under test. In this sense, active testing is not a suitable technique for interoperability testing, which is often carried out in operational networks. In such context, it is difficult to insert arbitrary testing messages without affecting the normal behavior and the services of the system. On the contrary, passive testing is a technique based only on observation. The tester does not need to interact with the SUT. This allows the test to be carried out without disturbing the normal operations of the system under test. Besides, passive testing also has other advantages such as: for embedded systems to which the tester does not have direct access, test can still be performed by collecting the execution traces of the system and then detect errors by comparing the trace with the behavior of the system described in its specification. In addition, passive testing makes it possible to moniter a system over a long period, and report abnomality at any time.

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25

Riese, Marc. "Model-based diagnosis of communication protocols /." [S.l.] : [s.n.], 1993. http://library.epfl.ch/theses/?nr=1173.

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26

Watkinson, John. "New protocols for asymmetric communication channels." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0012/MQ53396.pdf.

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27

Gerault, David. "Security analysis of contactless communication protocols." Thesis, Université Clermont Auvergne‎ (2017-2020), 2018. http://www.theses.fr/2018CLFAC103.

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28

Lee, Chungki. "Communication protocols in multi-hop radio networks." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/8199.

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29

Cavallero, Sara. "Medium Access Control Protocols for Terahertz Communication." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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This thesis proposes and studies a Medium Access Control (MAC) protocol for networks of tags deployed over an industrial machine using THz communications. Despite the great advantages of these frequencies, there are drawbacks that cannot be ignored, such as propagation delays that, even at small distances, are of the same order of magnitude as packet transmission times. For this reason, the mathematical models developed for Contention-Free and Contention-Based protocols take into account the propagation delay. The main focus of this thesis is on the CSMA/CA protocol, which introduces channel sensing to reduce collisions and increase performance. The performance of the protocol are compared with two benchmarks, based on Polling and Aloha, considering an industrial machine scenario and accounting for physical and MAC layers features.

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30

Ono-Tesfaye, Theodore. "Simulation and probabilistic validation of communication protocols." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0008/NQ60010.pdf.

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31

Debbage, Mark. "Reliable communication protocols for high-performance computing." Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358359.

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32

MuÌˆffke, Friedger. "A better way to design communication protocols." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411109.

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33

Chan, Serena 1977. "Multiple access protocols for multichannel communication systems." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/38439.

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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.
Includes bibliographical references (leaves 108-111).
System architecture design, evaluation, and optimization are key issues to developing communication systems that meet the requirements of today and expectations of the future. In this thesis, we introduce the concept of multiple access communication and the need to use efficient transmission techniques to expand both present and future wireless communication networks. We will study two areas regarding multiple access on multichannel communication systems. First, we describe fundamental multiplexing techniques that we can build upon and investigate the performance of different candidate architectures for the transmission of messages from bursty sources on multiple channels. We will consider traditional protocols such as Time Division Multiple Access (TDMA) and Slotted ALOHA (S-ALOHA) alongside a channelized architecture, which is based on the idea of multiplexing by dividing total transmission capacity into a fixed number of frequency channels. We develop mathematical models that describe the overall delay for sending large messages of a fixed length arriving from bursty sources and analyze their performances. We will make real-world parameter assumptions in the context of wireless networks and analyze the performance to develop intuition about the effectiveness of the different architectures. Second, we will investigate channel capacity allocation among mixed traffic, i.e., multiple classes of users. We will consider a first-come first-serve (FCFS) access strategy, a non-preemptive priority scheme, a preemptive resume priority scheme, and several channel capacity allocation schemes. We develop models that describe the overall delay for sending messages and analyze their performance. Our focus will concentrate on two classes of users. This scenario is typical of classes of users with small and large messages to transmit. present quantitative results by making real-world parameter assumptions in the context of wireless networks and analyze the performance to develop intuition about the effectiveness of each architecture.
by Serena Chan.
M.Eng.

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34

Yu, Shwuhwa Sarah. "Test sequence generation methods for communication protocols /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847309051639.

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35

Al-Hudhud, Ghada A. K. "Multi-agent communication protocols with emergent behaviour." Thesis, De Montfort University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422586.

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36

Zhou, Xiaoli. "Green Communication Protocols for Mobile Wireless Networks." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35809.

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Wireless networks enter a new era in which various objects, such as mobile phones, computers, vehicles, watches, are automatically and intelligently connected to provide ubiquitous services. Green communication protocols are required to save energy consumption and improve transmission performance. MAC protocols can detect the signal status and energy consumptions of physical channels to adapt to the dynamic wireless conditions. They can also provide node-to-node transmissions for network layer protocols under green wireless networks. The thesis presents three energy efficient communication solutions under different delay-tolerant networks scenarios to study the efficiency of MAC transmission protocols within wireless networks: CPMAC, AFLAS and TREE. CPMAC applies three energy-aware algorithms to transmit different quality requirements of data within one contact interval in sparsely connected sensor networks. Simulations and analysis shows CPMAC outperforms two other important MAC protocols in wireless sensor networks and vehicular ad-hoc networks in throughput, delay, energy consumption. AFLAS uses an adaptive frame length aggregation scheme for Vehicular Networks that is designed to improve transmission efficiency and increase data throughput. Suitable aggregation frame lengths are calculated according to the current wireless status, and applied in the MAC layer at the onset of data transmissions to save overhead and energy consumption. The simulations of AFLAS exhibit a significant improvement results in data throughput, retransmissions, overheads and transmission efficiency in comparison to non-adaptive aggregation schemes. TRaffic adaptive Energy Efficient MAC protocol (TREE) adapts its work modes: reservation and contention mode, to traffic density and adjusts its duty cycle to achieve energy efficiency. TREE demonstrates better performance in terms of energy efficiency and traffic adaptability than the schedule-based MAC protocol TDMA, the contention-based protocol CSMA and the traffic adaptive protocol TRAMA under mobile sensor network environments. By studying and designing MAC protocols in wireless environments, the thesis shows the comprehensive knowledge and principles of communication protocol designs with latency relaxed. Future work is discussed for further designs and implementations of green communication protocols.

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Scarlett, Jonathan Mark. "Reliable communication under mismatched decoding." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708413.

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38

Shahidi, Hamed. "Security Challenges of Communication Protocols in IoT : Comparing security features of ZigBee and Z-Wave communication protocols in IoT devices." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-40113.

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This research studies the security challenges in IoT devices. At first, security challenges have been described and then specifically the security of communication protocols in the IoT has been addressed. Finally, among different communication protocols, ZigBee and Z-Wave protocols have been chosen for this study. The criterion for choosing these two protocols is the level of security they provide for IoT devices to protect them against unauthorized access and hacking. Security, frequency, power consumption and data rate are the characteristics that have been discussed in the review of these two protocols. In the end, a comparison of the various features of these two protocols clarified that the security of IoT devices in each of these protocols depends on the type of the IoT device, the required range and other requirements, however, in most cases the ZigBee protocol showed more security than Z-Wave.

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39

Idate, Dileep Raghunath. "An intelligent communication controller for the VME bus." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52084.

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This document explains the design of the microcontroller based Intelligent Communication Controller (ICC) for the Motorola VMEbus. The card transmits and receives serial data on T1 medium at a rate of 1.544 Mbits/sec. This ICC card is a part of the communication system used in a current differential protection scheme for power distribution systems.
Master of Science

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40

Sun, Bo, and Shih-Ting Huang. "AUTOSAR Acceptance Test of Communication on CAN bus." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-143297.

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The aim of this thesis is to build a framework based on the CAN bus and to create the auto-run scripts followed by the AUTOSAR Acceptance Test for Arctic Core and Arctic Studio, the products from ARCCORE AB. Subsequent to this, the UART driver between the test bench and the application layer has been implemented. In total, 11 test cases are conﬁgured with the application layer, the run time environment (RTE) layer and the basic software (BSW) layer. Thus, the test bench of each test case is also implemented. The result shows that 82.7% test cases are passed and the CANTP module and the LDCOM module are found not supported in the Arctic studio.

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41

Uijen, Johan. "Learning Models of Communication Protocols using Abstraction Techniques." Thesis, Uppsala University, Department of Information Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111250.

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In order to accelerate the usage of model based verification in real life software life cycles, an approach is introduced in this thesis to learn models from black box software modules. These models can be used to perform model based testing on. In this thesis models of communication protocols are considered. To learn these models efficiently, an abstraction needs to be defined over the parameters that are used in the messages that are sent and received by the protocols. The tools that are used to accomplish this model inference are LearnLib and ns-2. The approach presented is demonstrated by learning models of the SIP and TCP protocols.

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42

Pompili, Dario. "Efficient Communication Protocols for Underwater Acoustic Sensor Networks." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16301.

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Underwater sensor networks find applications in oceanographic data collection, pollution monitoring, offshore exploration, disaster prevention, assisted navigation, tactical surveillance, and mine reconnaissance. The enabling technology for these applications is acoustic wireless networking. UnderWater Acoustic Sensor Networks (UW-ASNs) consist of sensors and Autonomous Underwater Vehicles (AUVs) deployed to perform collaborative monitoring tasks. The objective of this research is to explore fundamental key aspects of underwater acoustic communications, propose communication architectures for UW-ASNs, and develop efficient sensor communication protocols tailored for the underwater environment. Specifically, different deployment strategies for UW-ASNs are studied, and statistical deployment analysis for different architectures is provided. Moreover, a model characterizing the underwater acoustic channel utilization efficiency is introduced. The model allows setting the optimal packet size for underwater communications. Two distributed routing algorithms are proposed for delay-insensitive and delay-sensitive applications. The proposed routing solutions allow each node to select its next hop, with the objective of minimizing the energy consumption taking the different application requirements into account. In addition, a resilient routing solution to guarantee survivability of the network to node and link failures in long-term monitoring missions is developed. Moreover, a distributed Medium Access Control (MAC) protocol for UW-ASNs is proposed. It is a transmitter-based code division multiple access scheme that incorporates a novel closed-loop distributed algorithm to set the optimal transmit power and code length. It aims at achieving high network throughput, low channel access delay, and low energy consumption. Finally, an efficient cross-layer communication solution tailored for multimedia traffic (i.e., video and audio streams, still images, and scalar sensor data) is introduced.

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43

Vogt, Harald. "Protocols for secure communication in wireless sensor networks /." Zürich : ETH, 2009. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18174.

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44

Lluch, Lafuente Alberto. "Directed search for the verification of communication protocols." [S.l. : s.n.], 2003. http://www.freidok.uni-freiburg.de/volltexte/791.

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45

Kanter, Theo. "Adaptive Personal Mobile Communication, Service Architecture and Protocols." Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3273.

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46

Zhu, Jinsong. "Coverage analysis for conformance testing of communication protocols." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0002/NQ39013.pdf.

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47

Naraghi, F. "Communication protocols for distributed monitoring and control systems." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280539.

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48

Macedo, Raimundo Jose de Araujo. "Fault-tolerant group communication protocols for asynchronous systems." Thesis, University of Newcastle Upon Tyne, 1994. http://hdl.handle.net/10443/2021.

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It is widely accepted that group communication (multicast) is a powerful abstraction that can be used whenever a collection of distributed processes cooperate to achieve a common goal such as load-sharing or fault-tolerance. Due to the uncertainties inherent to distributed systems (emerging from communication and/or process failures), group communication protocols have to face situations where, for instance, a sender process fails when a multicast is underway or where messages from different senders arrive in an inconsistent order at different destination processes. Further complications arise if processes belong to multiple groups. In this thesis, we make use of logical clocks [Lamport78] to develop the concept of Causal Blocks. We show that Causal Blocks provide a concise method for deducing ordering relationships between messages exchanged by processes of a group, resulting in simple methods for dealing with multiple groups. Based on the Causal Blocks representation, we present a protocol for total order message delivery which has constant and low message space overhead (Le. the protocol related information contained in a multicast message is small). We also present causal order protocols with different trade-offs between message space overhead and speed of message delivery. Furthermore, we show how the Causal Blocks representation can be used to easily deduce and maintain reliability information. Our protocols are faulttolerant: ordering and liveness are preserved even if group membership changes occur (due to failures such as process crashes or network partitions). The total order protocol, together with a novel flow control mechanism, has been implemented over a set of networked Unix workstations, and experiments carried out to analyse its performance in varied group configurations.

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49

Chatzimisios, Periklis. "Performance modelling and enhancement of wireless communication protocols." Thesis, Bournemouth University, 2004. http://eprints.bournemouth.ac.uk/349/.

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In recent years, Wireless Local Area Networks(WLANs) play a key role in the data communications and networking areas, having witnessed significant research and development. WLANs are extremely popular being almost everywhere including business,office and home deployments.In order to deal with the modem Wireless connectivity needs,the Institute of Electrical and Electronics Engineers(IEEE) has developed the 802.11 standard family utilizing mainly radio transmission techniques, whereas the Infrared Data Association (IrDA) addressed the requirement for multipoint connectivity with the development of the Advanced Infrared(Alr) protocol stack. This work studies the collision avoidance procedures of the IEEE 802.11 Distributed Coordination Function (DCF) protocol and suggests certain protocol enhancements aiming at maximising performance. A new, elegant and accurate analysis based on Markov chain modelling is developed for the idealistic assumption of unlimited packet retransmissions as well as for the case of finite packet retry limits. Simple equations are derived for the through put efficiency, the average packet delay, the probability of a packet being discarded when it reaches the maximum retransmission limit, the average time to drop such a packet and the packet inter-arrival time for both basic access and RTS/CTS medium access schemes.The accuracy of the mathematical model is validated by comparing analytical with OPNET simulation results. An extensive and detailed study is carried out on the influence of performance of physical layer, data rate, packet payload size and several backoff parameters for both medium access mechanisms. The previous mathematical model is extended to take into account transmission errors that can occur either independently with fixed Bit Error Rate(BER) or in bursts. The dependency of the protocol performance on BER and other factors related to independent and burst transmission errors is explored. Furthermore, a simple-implement appropriate tuning of the back off algorithm for maximizing IEEE 802-11 protocol performance is proposed depending on the specific communication requirements. The effectiveness of the RTS/CTS scheme in reducing collision duration at high data rates is studied and an all-purpose expression for the optimal use of the RTS/CTS reservation scheme is derived. Moreover, an easy-to-implement backoff algorithm that significantly enhances performance is introduced and an alternative derivation is developed based on elementary conditional probability arguments rather than bi-dimensional Markov chains. Finally, an additional performance improvement scheme is proposed by employing packet bursting in order to reduce overhead costs such as contention time and RTS/CTSex changes. Fairness is explored in short-time and long-time scales for both the legacy DCF and packet bursting cases. AIr protocol employs the RTS/CTS medium reservation scheme to cope with hidden stations and CSMA/CA techniques with linear contention window (CW) adjustment for medium access. A 1-dimensional Markov chain model is constructed instead of the bi-dimensional model in order to obtain simple mathematical equations of the average packet delay.This new approach greatly simplifies previous analyses and can be applied to any CSMA/CA protocol.The derived mathematical model is validated by comparing analytical with simulation results and an extensive Alr packet delay evaluation is carried out by taking into account all the factors and parameters that affect protocol performance. Finally, suitable values for both backoff and protocol parameters are proposed that reduce average packet delay and, thus, maximize performance.

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Jin, S. "Temporal logic specification and verification of communication protocols." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378819.

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Dissertations / Theses on the topic 'Communication protocols and bus'

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