A Dependency-Aware Hierarchical Service Model for SaaS and Cloud Services

Service-Oriented Computing is known as a new computing paradigm that utilizes existing services as fundamental elements for developing distributed applications based on the so-called "use, not own" manner. In this paper, services are classified into three levels in accordance with different business requirements. Services are assembled by choosing lower-level services or other services at the identical level. Tenant applications are implemented by way of choosing services in composite business level. A hyper graph-based service model is used to represent hierarchical services and multi-tenancy applications. A dependency is a relation between services wherein a change to one of the services implies a potential change to the others. We propose algorithms based on directed hyper graph which can represent dependencies between services and applications to verify the correctness of dependencies during the application construction period and we implement a SCA-based platform for the large-scale multi-tenancy application construction.