Finding available services in TOSCA-compliant clouds

The OASIS TOSCA specification aims at enhancing the por-ta-bility of cloud applications by defining a language to describe and manage them across heterogeneous clouds. A service template is defined as an orchestration of typed nodes, which can be instantiated by matching other service templates. In this paper, we define and implement the notions of {em exact} and {it plug-in matching} between TOSCA service templates and node types. We then define two other types of matching ({em flexible} and {em white-box}), each permitting to ignore larger sets of non-relevant syntactic differences when type-checking service templates with respect to node types. The paper also describes how a service template that plug-in, flexibly or white-box matches a node type can be suitably adapted so as to exactly match it.