Exploring the potential of global types for adding a choreography perspective to the jABC framework

We discuss how global types, aka multiparty session types, provide a complementary perspective on workflow models within the jABC modeling framework. On a reference example from the Semantic Web Services Challenge we show how the service orchestrations of jABC workflow applications can be expressed as service choreographies based on global types. Roles, identified with sets of logically related Service-Independent Building Blocks (SIBs), bridge between the two ways of looking at the behavior of systems. We compare the degree of declarativity and robustness in the face of changes of the reference example modeled with the jABC framework with as a global types specification.