Simulating mobile and distributed systems with DEUS and ns-3

Mobile and distributed systems are characterized by decentralized goals and control, with high levels of concurrency and asynchronous interaction. Their qualitative and quantitative analysis is usually based on discrete event modeling and simulation. As most simulation tools target a specific class of problems, only a few of them may be considered truly general-purpose, yet they can hardly support the analysis of distributed systems with thousands of nodes, characterized by a high level of churn (node joins and departures) and reconfiguration of connections among nodes. To fill this gap, a few years ago we started developing an open-source, general-purpose and discrete event simulation tool, called DEUS, which is application-level oriented, Java-based, and characterized by ease of use and flexibility. However, it does not provide any package for simulating networking layers and their implementation is not foreseen, since a number of specialized tools are already available. In this paper, we present a general methodology for achieving a more realistic DEUS-based simulation of mobile and distributed systems, by leveraging on ns-3, which is generally known as a highly reliable and complete open-source tool for the discrete event simulation of Internet systems. In particular, we describe our positive experience in using ns-3´s LTE-EPC package to support the simulation of a peer-to-peer overlay scheme called Distributed Geographic Table (DGT), which allows mobile nodes to efficiently share information without centralized control.