GNS3 - GNS3 is a graphical network simulator that allows simulation of complex networks.

AnyLogic - AnyLogic has changed simulation modeling and expanded its application into complex business environments. The unmatched flexibility of multimethod modeling allows users to capture the complexity of virtually any system, at any level of detail.

ns-3 - a discrete-event network simulator for internet systems

NetSim - NetSim software was created to simulate various Cisco systems. Cisco software is known around the world as being one of the best network, routing and switch systems for businesses and private use. Read more about NetSim.

Ranplan Wireless - Ranplan Wireless is a leading platform that has revolutionized itself with innovative wireless tools and software based on extensive technology.

Paessler Multi Server Simulator - Paessler Multi Server Simulator is inexpensive and robust software that helps you power massive-scale testing.