Service Selection with Uncertain Context Information

Abstract

The current evolution of Service-Oriented Computing in ubiquitous systems is leading to the development of context-aware services. Context-aware services are services of which the description is enriched with context information related to non-functional requirements, describing the service execution environment or its adaptation capabilities. This information is often used for discovery and adaptation purposes. However, in real-life systems, context information is naturally dynamic, uncertain, and incomplete, which represents an important issue when comparing the service description with user requirements. Uncertainty of context information may lead to an inexact match between provided and required service capabilities, and consequently to the non-selection of services. In this chapter, we focus on how to handle uncertain and incomplete context information for service selection. We consider this issue by presenting a service ranking and selection algorithm, inspired by graph-based matching algorithms. This graph-based service selection algorithm compares contextual service descriptions using similarity measures that allow inexact matching. The service description and non-functional requirements are compared using two kinds of similarity measures: local measures, which compare individually required and provided properties, and global measures, which take into account the context description as a whole.

Service selection in mobile environments: considering multiple users and context-awareness

“…the context information is exogenously given regarding the service composition, like weather), we speak of the dynamic nature of context information when the set of selected service objects influences the actual manifestation of the context information (cf. Damián-Reyes, Favela, & Contreras-Castillo, 2011; Vanrompay et al, 2009). Examples for such context information are daytime-dependent availability of service objects (i.e.…”

“…Ai & Tang, 2008; Deng, Huang, Hu, Zhao, & Wu, 2016; Sandionigi, Ardagna, Cugola, & Ghezzi, 2013; Vanrompay, Pinheiro, & Berbers, 2009; Yu & Reiff-Marganiec, 2009; Zhou, Zheng, Song, Du, & Chen, 2008). Few of them also consider context-based dependencies that could exist within a certain part or the entire service composition of a user (e.g.…”

A user-centric vision of service-oriented Pervasive Information Systems

“…Different proposals for semantic description of contextaware services can be found in the literature [24][38][39] [41]. Most of them are used for service discovery [25][39] or composition [25].…”

“…For [24][39], context is seen as a nonfunctional aspect of service. For others, such as [41], context is seen as condition for the execution of a service. In both cases, a semantic matchmaking is performed between context information related to the service and the one related to user or execution environment.…”

“…Such adaptation capabilities are often based on a semantic description of such services. Context-aware services can then be defined as services whose description is associated with contextual properties, i.e., services whose description is enriched with context information indicating the situations to which the service is adapted to [41].…”