Interaction in distributed component based architectures can become a rather complex and error prone issue. As it is good practice to keep application concerns separated from infrastructural ones, component based applications typically rely on communication middleware to cope with matters of distributed heterogeneous interaction. Unfortunately, generic middleware tends to be monolithic, heavyweight software which is unacceptable in resource constrained embedded systems. Communication middleware for distributed embedded systems has to be custom tailored to the application’s interaction needs and therefore shall be as lightweight as possible. By applying the component paradigm to the communication middleware and introducing connectors as first class architectural entities, it becomes feasible to automatically synthesize application specific middleware from the application’s architectural models and a set of prefabricated communication primitives. We contribute by specifying these structural designs for explicit connectors and by identifying the classes of their basic building blocks, thus providing a sound foundation for middleware synthesis.

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The number of electronic systems in cars is continuously growing. Electronic systems, consisting of so-called electronic control units (ECUs) interconnected by a communication network, account for up to 30% of a modern car’s worth. Consequently, software plays an ever more important role, both for the implementation of functions and the infrastructure. In order to benefit from the reuse of software modules, the major automotive companies have standardized a large number of these modules in the context of the AUTOSAR consortium. In this paper we propose the refactoring of the AUTOSAR stack of system software modules by applying the componentbased paradigm in order to increase the scalability of the software stack according to the requirements of the application. We demonstrate the feasibility of this approach by performing the refactoring of the modules FlexRay Driver and FlexRay Interface as an example and by deploying the resulting refactored components in a sample automotive application. Finally we measure the execution time as well as the memory consumption of the refactored components and compare these measures to the measures obtained from the corresponding ordinary AUTOSAR modules

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To reduce time and cost to market of automotive software systems and simultaneously increase the products’ quality, the component paradigm has found broad acceptance within the automotive industry over the last few years. This fact is reflected by upcoming domain specific software standards like AUTOSAR. In AUTOSAR application concerns are covered by software components, while infrastructural ones are handled within layered component middleware. The so gained separation of concerns leads to an increase in application quality, reusability and maintainability, and hence to a reduction of cost and time to market. This paper contributes with the consequent application of the component paradigm to AUTOSAR’s layered middleware, thereby gaining all benefits of CBSE not only for the application level but for the whole automotive software system. The introduced component model for middleware components can flexibly be used to build resource-aware, AUTOSAR compliant, component middleware for distributed automotive software systems and can seamlessly be integrated within the AUTOSAR system architecture.

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During the last years, component based software development has become a well accepted software engineering paradigm within the automotive industry. This fact is not only reflected by upcoming development tools but also by newly arising automotive software standards. In component based software engineering, applications are built by assembling small reusable building blocks, the components. Typically more than one component implementation meets the application developer's requirements, so proper selection of the assembled components becomes a key element of the whole procurement and engineering process. This paper's contribution is twofold: First, a basic set of performance and dependability metrics and measures for automotive components is identified. Second, a unified benchmarking process is proposed, that allows an unambiguous comparison of distinct component implementations of a given component class.

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In component based software engineering, an application is build by composing trusted and reusable units of execution, the components. A composition is formed by connecting two components' related interfaces. The point of connection, namely the connector, is an abstract representation of their interaction. Most component models' implementations rely on extensive middleware, which handles component interaction and hides matters of heterogeneity and distribution from the application components. In resource constrained embedded systems this middleware and its resource demands are a key factor for the acceptance and usability of component based software. By addressing connectors as first class architectural entities at model level, all program logic related to interaction can be located within them. Therefore the set of all explicit connectors of a component architecture denotes the exact requirements of that application's communication and interaction needs. We contribute by demonstrating how to use explicit connectors in model driven development to synthesize a custom tailored, component based communication middleware. This synthesis is achieved by model transformations and optimizations using prefabricated basic building blocks for communication primitives.

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When building a system by connecting components, the connection itself, the connector, becomes a hot-spot of abstraction for any interaction. In contrary to most existing component models, we introduce explicit connectors as first class architectural entities. They materialize detailed contracts regarding composition, deployment and interaction and hence provide fine granular information on composed structures. Using explicit connectors results in customtailored and consequently light-weight middleware, as any interaction logic is contained within them. Modeling component architectures with explicit connectors allows the usage of off-the-shelf connector libraries. Thereby, developing a distributed component based application becomes less complex and more competitive due to reduced costs and increased reliability. We contribute by adopting a model driven development process for the use of explicit connectors by extending the syntax of UML 2.0 and defining a set of required model transformations.

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The increasing complexity of today's embedded systems applications imposes the requirements and constraints of distributed, heterogeneous subsystem interaction to software engineers. These requirements are well met by the component based software engineering paradigm: complex software is decomposed into coherent, interacting units of execution, the so called components. Connectors are a commonly used abstraction to model the interaction between them. We consequently contribute with the application of explicit connectors for distributed embedded systems software. Explicit connectors encapsulate the logic of distributed interaction, hence they provide well defined contracts regarding properties of inter-component communication. Our approach allows model level validation of component composition and interaction incorporating communication related constraints beyond simple interface matching. In addition, by using explicit connectors, the complexity of application components is reduced without the need for any heavy weight middleware. In fact, the set of all deployed explicit connectors forms the smallest possible, custom tailored middleware.

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When building a component based application for distributed embedded systems, its overall behavior depends not only on the contracts applying to the components and their interfaces, but even more so on explicit as well as implicit connectors emerging from component composition, deployment and interaction. Explicit connectors provide additional contracts on resource requirements and information channels. We contribute by showing how to perform model level validation of component and contract composition beyond simple interface matching. Moreover, we discuss a classification of typical component connectors to simplify application development for distributed embedded systems. This avoids the need of extensive knowledge of communication subsystems and the existence of any heavy weight middle-ware.

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