QoS-aware query relaxation for service discovery with business rules

• We propose an annotation mechanism to describe business-driven QoS.
• We propose a business-driven filtering mechanism to eliminate unsuitable services.
• We propose a ranking method based on QoS preferences and constraints.
• We propose query relaxation methods for single service query or composite one.
• Experimental results show that the proposal can effectively discover services.

Service discovery, the process of locating web services capable of satisfying the requirements of service requesters, plays a crucial role in the development of user-centric, service-oriented applications; however, most current service discovery mechanisms do not focus on integrating various business-driven quality of service (QoS) attributes or establishing relaxation mechanisms to enhance search results. This research proposes a systematic approach, referred to as business-rule-based service discovery (BRSD), to address the above issues. The main features of the proposed approach are as follows: (1) a business rule annotation mechanism that includes condition rules, enumeration rules, and applied utility references; (2) the ability to eliminate unsuitable services through the application of filters to deal with kernel properties, provider constraints, and user constraints; (3) the calculation of service ranking scores for single services or service sets according to QoS constraints and QoS importance ranking; and (4) the ability to retrieve suitable single services as well as service sets using the proposed two-point and incremental service query relaxation mechanisms.