Abstract. The proliferation of smart spaces and emergence of new standards, such as Web Services, have paved the way for a new breed of software systems. Often the complete functional and QoS requirements of such software systems are not known a priori at design-time, and even if they are, they may change at run-time. Unfortunately, the majority of existing software engineering techniques rely heavily on human reasoning and manual intervention, making them inapplicable for automatic composition of such software systems at run-time. Moreover, these approaches are primarily intended to be used by technically knowledgeable software engineers, as opposed to domain users. In this paper, we present Service Activity Schemas (SAS), an activity-oriented language for modeling software system's functional and QoS requirements. SAS targets service-oriented software systems, and relies on an ontology to provide domain experts with modeling constructs that are intuitively understood. SAS forms the centerpiece of a framework intended for user-driven composition and adaptation of service-oriented software systems in a pervasive setting. We provide a detailed description of SAS in the context of a case study and formally specify its structural and dynamic properties.  Software systems are increasingly permeating a variety of domains, including medical, industrial automation, defense, and emergency response. The growth of service-oriented software systems and the emergence of new standards have made it possible to develop pervasive systems that were not even conceivable a few years ago. In particular, the decoupling of service providers from consumers and the flexibility of dynamically discovering and binding to services have facilitated the development of software systems intended for execution in smart spaces. The proliferation of portable and embedded computing devices and the recent advances in wireless network connectivity have further made the service-oriented architecture (SOA) paradigm a viable option in such settings. Web Services [1] have also played a crucial role in enabling interoperability and alleviating integration challenges in pervasive settings.
The SASSY framework REF provides service activity schemas and service sequence scenarios to specify QoS requirements in service-oriented architectures.
A modeling language for activity-oriented composition of service-oriented software systems
In Proc. of the 12th Int. Conf. on Model Driven Engineering Languages and Systems
Computer Science