Capturing Web Services Provider Constraints - An Algorithmic Approach

摘要

In the SOA paradigm service composition enables creation of business processes and workflows by assembling together simple or composite services in a particular sequence. In such a distributed architecture possibly involving multiple service providers, optimal selection of service implementations from an existing pool of services, based on QoS and cost factors assumes critical practical relevance. In this paper, we analyze various complex service provider configurations, where multiple business functionalities (comprising a business process) are available as simple or composite services from multiple service providers (some possibly working in coalitions) at varying QoS and cost attribute values. We study the service composition constraints resulting in such a context and propose an algorithm to formally capture these special constraints and represent these into simple weighted multi-stage graphs suitable for subsequent application of various optimization techniques cited in the literature.