Emergent Software Services

Services are normally composed following a structured model, or based on a particular goal that needs to be fulfilled. Such model is problematic for pervasive environments, since service components deployed in the environment are unknown beforehand. As a result, services may never execute due to the unavailability of one of the pre-specified components, or components missing to fulfill the service goal. This paper posits a new vision for service composition by inverting the control flow of service-oriented applications between users and the environment. Rather than having to request a particular service, services emerge from the environment based on interactions between available service components, and are pushed to be utilized by users. We present the architecture required to fulfill our vision in enabling service emergence in a pervasive environment. This vision architecture is realized by an initial prototype framework for software service emergence called Mordor. Early results of this vision are obtained from two examples demonstrating the feasibility of services emergence from previously unknown service components, and a case study demonstrating Mordor's usability in real world scenarios.