This document discusses different types of network simulators that can be used in MATLAB. It lists several open-source simulators like NS-2, NS-3, Omnet++ and proprietary simulators like Qualnet and Opnet. It also mentions some current research projects using network simulation in areas like supercomputer networks, isolated power systems, rumor routing protocols and wireless applications. Finally, it provides examples of modern research topics involving areas like smart grids, mobile network simulation, caching systems and taxi dispatching.