Packet tracer is an interactive network simulation tool.Packet tracer helps to establish an logical or physical network just doing drag and drop of virtual Cisco router and switches and other cisco security devices. There is an interactive shell to write the configuration command to run , operate and troubleshoot cisco devices and networks. It is specially for the student of cisco networking academy to simulate and troubleshoot a big or small virtual network and have a clear concept on them.
Packet Tracer is helpful for students who really need to design complex and large networks, which is often not possible with physical hardware, due to costs.In packet tracer software students are not only be able to use only cisco routers and switches but also very costly cisco security appliance i.e ASA()Adaptice Security Appliance) which is very expensive in real life.
Previously it was free only for the student of cisco network academy but now from 2018 it is free to Download for all who are interested.Latest version 7.2 are available now.
Packettracer for Windows(32bit):
Packettracer for Windows(64bit):
Packettracer for LINUX(64bit):