Cisco Packet Tracer is a cross-platform network simulation tool that allows you to arrange nodes and connecting lines and emulate computer networks. The software serves as an educational tool for Certified Cisco Network Associate students. But, advanced users can also use this to create network topologies and learn fundamental CCNA concepts. You can use this to simulate the configuration of Cisco routers and switches. The program presents a model of a command-line interface where you can drag and drop network devices as you see fit. This will help you understand network behavior and possibly discover new network ideas.