Choreography Modeling and Analysis with Collaboration Diagrams

UML collaboration diagrams (called communication diagrams in [8]) provide a convenient visual model for specifying Web Service choreographies. A choreography specifies the desired set of interactions among a set of Web services. We formalize the interactions among Web services as conversations, i.e., the sequence of messages exchanged among the services, recorded in the order they are sent. This paper reviews our recent results on the realizability problem for choreographies specified as collaboration diagrams [4, 5]. The realizability problem investigates the following question: Is it possible to construct a set of peers that generate exactly the same set of conversations specified by a given choreography? To study this problem, we model a set of Web services (i.e., peers) as a set of communicating finite state machines [3] and we identify a set of sufficient conditions for realizability of a class of collaboration diagrams.