We propose extending these middleware approaches with suitable abstractions to better support protocolbased interaction in mobile applications. To test our approach, we created ObjectPlaces, a middleware that es as its main abstraction. A role encapsulates an application component's behavior during an interaction protocol. A role's behavior is a black box to ObjectPlaces; rather than focus on specifying a ehavior, we emphasize the role abstraction. This lets ObjectPlaces manage the setup of interaction sessions among several roles played by application components on different nodes and active session maintenance in a mobile and dynamic application. ed ObjectPlaces in the domain of automatic guided vehicle control and evaluated our abstractions by applying them to the AGV application's coordination problems. Problem illustration We undertook a research project with an industry partner, Egemin, to explore a decentralized approach's feasibility for AGV control. AGVs ar...