In order to tackle the controller synthesis problem for large-scale discrete-event systems, recent approaches suggest the design of interacting modular or decentralized supervisors. In these works, information exchange between the supervisors is either required implicitly by the synchronization of shared events or explicitly by the communication of events or symbols. However, it is not discussed how the communication can be realized if the supervisors are implemented in distributed controller devices that are connected by a communication network. In this paper, we study the synchronization of shared events among distributed supervisors on a switched network. In particular, we develop a communication model that accounts for possible transmission delays, and enables the correct operation of the communicating supervisors.