FlexSim - Simulation software to model, simulate, predict, and visualize systems in manufacturing, material handling, healthcare, warehousing, mining, etc.
ns-3 - a discrete-event network simulator for internet systems
VNX - VNX is a simple, fast, and highly effective virtualization tool developed to assist you in creating virtual network testbeds automatically, resulting in time-saving.
Cisco Packet Tracer - Download Cisco Packet Tracer, an innovative network simulation and visualization tool used by Cisco Networking Academy students and instructors.
OPNET - OPNET is a next-gen and highly resourceful network simulator tool that enables engineers and other professionals to simulate the performance and output of any network type.
Cisco VIRL - Cisco VIRL is a next-gen network virtualization and orchestration platform that enables you to accomplish multiple tasks like creating and customizing simulated networks with third-party and Cisco objects by means of a graphical utility.