Echtzeit-Ethernet Restbussimulation: Frühzeitiges Modellbasiertes Testen in Fahrzeugnetzwerken der nächsten Generation

Die zunehmende Komplexität automobiler Netzwerke und deren steigende Bandbreitenanforderungen bei gleichzeitiger Einhaltung von Zeitaussagen erfordern neue Konzepte in der Vernetzung elektronischer Komponenten im Fahrzeug. Echtzeit-Ethernet ist ein geeigneter Kandidat diese Problemstellung zu lösen. Um frühzeitig im Entwicklungsprozess Komponenten und Systeme zu testen hat sich die Restbussimulation als adäquates Mittel etabliert. In dieser Thesis wird eine Restbussimulationsmethodik für Echtzeit-Ethernet-Netzwerke entwickelt, mit der es möglich ist, Systeme in frühen Entwicklungsphasen auf funktionale und nicht-funktionale Anforderungen mittels abstrakter Testfälle zu testen. Dazu wird auf die Modellierung von zeitlichen Anforderungen von Echtzeit-Ethernet-Systemen eingegangen und ein abstraktes Testfallmodell entwickelt, das Testfälle nicht-funktionaler Leistungsanforderungen beschreibt und gleichzeitig als Simulationsmodell für den Restbussimulator dient. Die entwickelte Methodik wird anschließend exemplarisch an einer Automotive-Echtzeit-Ethernet- Anwendung angewendet.The increasing complexity of automotive networks, their time constraints, and their increasing bandwidth demands requires new concepts for connecting electronic automotive components. Real-time Ethernet is a suitable candidate to solve this problem. In order to allow testing components and systems at early development stages, cluster simulation has been established as an adequate manner. In this thesis, a method for cluster simulation of real-time Ethernet systems is developed, in order to allow testing systems in early design stages, by using abstract test cases. Additionally, a requirement modeling approach for non-functional requirements of real-time Ethernet systems is presented. An abstract test case model is developed, which describes test cases for non-functional performance requirements. It is simultaneously utilized as the simulation model for the cluster simulation environment. The developed methodology is exemplarily applied to an automotive real-time Ethernet system

Leistungsmessung von Time-Triggered Ethernet Komponenten unter harten Echtzeitbedingungen mithilfe modifizierter Linux-Treiber

Diese Arbeit befasst sich mit dem Echtzeitübertragungsprotokoll Time-Triggered Ethernet. Es werden zuerst Grundlagen einer Echtzeiterweiterung im Linux-Kernel und dem Standard Ethernet behandelt. Eine anschließende genaue Betrachtung von Time-Triggered Ethernet folgt. Aufbauend auf den Grundlagen wird die Implementierung einer Messsoftware und die dazugehörige Modifizierung von Linux-Treibern erklärt und im Folgenden die Ergebnisse aus der Messung diskutiert.This thesis deals with the real-time transmission protocol Time-Triggered Ethernet. At first the fundamentals of a real-time Linux-Kernel-extension and the standard Ethernet are covered. A detailed analysis of Time-Triggered Ethernet follows. Building on the basic principles the implementation of a measurement software and the associated modification of Linux drivers are explained. In conclusion the results from the measurement are discussed

Performance Analysis of Time-Triggered Ether-Networks Using Off-the-Shelf-Components

The performance analysis and validation of distributed real-time systems poses significant challenges due to high accuracy requirements at the measurement tools. A fully synchronized time-scale at ultrafine granularity is not easy to generate. Even though there are several analyzer tools for standard switched Ethernet, these tools cannot be applied in time-triggered networks, since they do not meet the requirements of synchronized packet generation. This paper introduces a low cost and lightweight approach to measure end-to-end latency of time-triggered Ethernet traffic with off-the-shelf components. By using standard computer hardware and a real-time Linux Kernel, it is shown that measurement can be achieved in a resolution of microseconds. Furthermore, a validation with an Ethernet performance analyzer and a mathematical framework is presented to check the given results

Real-time Ethernet Residual Bus Simulation

The increasing complexity of automotive networks, their challenging timing constraints and their high bandwidth demands require new concepts for future in-car communication. Real-time Ethernet is meant to be a suitable candidate for the next-generation in-car interconnection. However, model-based testing capabilities must be available as well. Applications must be validated prior the first assembly, due to the distributed development process. Methods like residual bus simulation are of particular interest to allow for testing systems in early development stages by emulating unfinished or not available parts of the system. In this paper, we present a methodology and a feasibility study of a residual bus simulation in automotive real-time Ethernet systems. The challenges of applying this testing method in real-time Ethernet based networks with parallel packet transmission are outlined and compared to today's automotive bus system simulation approaches. Furthermore, the combination of different model-based testing techniques, that are not used in state-of-the-art commercial tools, are applied for the validation of non-functional timing requirements. An extension to an existing abstract test case model is proposed, which allows modelling temporal attributes. It is simultaneously used as simulation model to drive the residual bus simulation. We demonstrate the approach's feasibility by implementing a prototype residual bus simulator for real-time Ethernet networks and applying it to an example application.Unknow