COCOA : ConversationBased Service Composition for Pervasive Computing Environments

Abstract

Pervasive computing environments are populated with networked services, i.e., autonomous software entities, providing a number of functionalities. One of the most challenging objectives to be achieved within these environments is to assist users in realizing tasks that integrate on the fly functionalities of the networked services opportunely according to the current pervasive environment. Towards this purpose, we present COCOA, a solution for COnversation-based service COmposition in pervAsive computing environments with QoS support. COCOA provides COCOA-L, an OWL-S based language for the semantic, QoSaware specification of services and tasks, which further allows the specification of services and tasks conversations. Moreover, COCOA provides two mechanisms: COCOA-SD for the QoS-aware semantic service discovery and COCOA-CI for the QoS-aware integration of service conversations towards the realization of the user task's conversation. The distinctive feature of COCOA is the ability of integrating on the fly the conversations of networked services to realize the conversation of the user task, by further meeting the QoS requirements of user tasks. Thereby, COCOA allows the dynamic realization of user tasks according to the specifics of the pervasive computing environment in terms of available services and by enforcing valid service consumption.

Automatic Service-Integration Framework for Ubiquitous Environments

“…They emphasize three important characteristics for service composition: dynamicity ( [7], [8]), automaticity and context-awareness ( [8], [9]) of the composition. While a certain number of works dealt with the dynamicity and context awareness of service-composition, few were interested in providing a real automaticity.…”

Towards runtime discovery, selection and composition of semantic services

“…In [29] and [30], the authors explore the use of semantic services as basic constructs in pervasive environments. The different devices and functionality in the environment are exposed as services, and then these services are composed as they are required, to match the user needs.…”

COCOA: COnversation-based service COmposition in pervAsive computing environments with QoS support

“…Specifically, a pervasive service corresponds to an autonomous networked entity, which provides a set of capabilities. A service capability then corresponds to either a primitive operation of the service or a process composing a number of operations (also referred to as conversation) [20]. Consumption of services by client applications (which may themselves realize more complex services available on the network) further requires service clients and providers to agree on both the functional and non-functional semantics of capabilities, so that they can integrate and interact in a way that guarantees dependable service provisioning and consumption.…”

“…COCOA allows the dynamic realization of user tasks from networked services available in the pervasive computing environment. A preliminary effort for defining COCOA has been presented in [20]. In this article, we present the extension of COCOA with support of Quality of Service (QoS).…”