DHS: the Distributed Hybrid Simulator

The Distributed Hybrid Simulator (DHS) employs three different simulation models, that act at two different levels, i.e., a coarse simulator (Level 0) that can trigger the execution of two Level 1 simulators (i.e. Level 1a and Level 1b) that can be executed sequentially. Such simulators are distributed and executed in different networked hosts. In DHS, the Smart Shire Simulator (S3) is used as a Level 0 simulator. More in detail, S3 is an agent-based prototype implemented on top of the GAIA/ARTÌS simulation middleware. The Level 0 simulator interacts with both the Level 1a: ADVISOR based simulator and the the Level 1b: OMNeT++ simulator. The interactions among the simulators are quite complex. In practice, they are based on a set of wrappers that implement message-passing calls encapsulated in TCP-based connections.