Abstract. The coordination language Reo defines circuit-like connectors to steer the collaboration of independent components. In this paper, we present a framework for the modeling of distributed, self-reconfigurable connectors based on algebraic graph transformations. Reconfiguring a connector that is composed with others, may involve a change of shared interfaces and may therefore require a reconfiguration of the surrounding connectors as well. We present a method of synchronized local reconfigurations in this setting and discuss a bottom-up strategy for coordinating synchronized reconfigurations in a connector network. We exploit the double-pushout approach for the modeling of reconfigurations, and propose an adaptation of the concept of amalgamation for synchronizing reconfigurations. We use a nondeterministic scheduler as our running example. 1

Abstract. Increasing sizes of present-day distributed software systems call for coordination models which are both modular and scalable. Precise modelling of real-life applications further requires the notion of real-time. In this paper, we present a modular formal development of a compositional model for real-time coordination in dataflow networks. While real-time dataflow networks are typically asynchronous, our approach includes coordination patterns which combine, but are not limited to, synchrony and asynchrony. We define a constraint- and SAT-based encoding, which allows us to benefit from high-end constraint solving techniques when inspecting valid interactions of the system. Keywords: Real-Time Dataflow Networks, Component-Based Software Construction, Coordination, Constraint Solving, SAT.

In recent years, a promising line of research on formal compositional models for component connectors [3–6, 8, 9] has demonstrated the merits of having connectors as first class concepts, and incrementally increased the expressiveness of the interaction protocols that can be captured compositionally. Typically, in these

Abstract. In the area of component-based software architectures, the term connector has been coined to denote an entity (e.g. the communication network, middleware or infrastructure) that regulate the interaction of independent components. Hence, a rigorous mathematical foundation for connectors is crucial for the study of coordinated systems. In recent years, many different mathematical frameworks have been proposed to specify, design, analyse, compare, prototype and implement connectors rigorously. In this paper, we overview the main features of three notable frameworks and discuss their similarities, differences, mutual embedding and possible enhancements. First, we show that Sobocinski’s nets with boundaries are as expressive as Sifakis et al.’s BI(P), the BIP component framework without priorities. Second, we provide a basic algebra of connectors for BI(P) by exploiting Montanari et al.’s tile model and a recent correspondence result with nets with boundaries. Finally, we exploit the tile model as a unifying framework to compare BI(P) with other models of connectors and to propose suitable enhancements of BI(P). 1