Abstract
Middleware mediated transactions (MMT) integrate message-oriented transactions and distributed object transactions. MMT are suggested as an evolutionary and integrative approach to support reliable and flexible interactions between heterogeneous and autonomous components, which is a major challenge in enterprise application integration. MMT offer the ability to combine communication of messages and notifications with conventional transactional object requests. Thus MMT introduce the flexibility of mediated interactions with respect to topology, binding, time-dependencies and content transformation into distributed object transactions. MMT are characterized by coupling modes to control if notifications become visible immediately or are dependent on the transaction status, to include mediators as transaction participants, and to distinguish between message delivery and processing, as well as vital and non-vital participants. Furthermore, coupling modes interrelate different distributed transaction contexts of publishers and subscribers. This paper introduces the concept of MMT and presents two system prototypes implementing MMT, the dependency-spheres middleware service and the X2 TS middleware service.