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Service-oriented computing paradigms have considerably enhanced support for dynamic in modern computing environments by providing loosely coupled interactions between components. The key attainment is the ability to perform a late binding of service compositions, i.e., an allocation of actual services to service placeholders during runtime. However, this attainment is limited to the binding of services and cannot operate on the service composition plans itself. Moreover, many service composition representations do not consider the realtime behavior of single services, failing to address a key need of service compositions within dynamic environments that are characterized by a high node mobility.Within this paper, we introduce a service composition model based on a bipartite graph representation that enables the rapid modification of already existing service composition plans. Here, the workflow within a service composition is modeled with a timed automaton while a labeled digraph ensures the correct flow of data between the single services.

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Human-centric computing has grown to be the major influence in today's computing research. Due to demand from industry and even lawmakers for easy-to-use computer systems, the user is now regarded as being the center of a ubiquitously available environment that supports the execution of task and anticipates user actions. This environment allows for the establishment of completely new ways for the delivery of legacy services and represents an opportunity for the introduction of a new type of services, addressing the user-focused service consumption. As a cause of this shift, the increasing saturation of everyday environments with computing devices can be identified. This saturation implies a numerical growth of computing systems and entails an increasing complexity, which negatively influences maintainability and manageability. Moreover, the shortcomings caused by the mobility of system elements, a common trait of human-centric environments, require consideration about the reliability of cooperative actions. In this paper, we present an approach that copes with complexity and dynamic while making service-oriented systems autonomous by the use of bio-inspired concepts. In particular, the aim is to make service architectures environment-aware. Thus, service architectures are supposed to adapt autonomously to their current environment like biological species do to survive. This approach requires services to obtain knowledge about characteristics and state of the environment through gathering semantically enhanced information about the context of the computing environment, which is intended to help in forming a virtual counterpart of the real world as reference for service adaptation. For this purpose, we illustrate the architecture for context provisioning in highly dynamic computing environments. As base for this architecture a middleware is introduced utilizing a loosely coupled interaction model. Moreover, a pheromone-based concept is outlined to optimize the dissemination of context data in the absence of adequate context sources.