ns-3
discrete-event network simulator for Internet systems, targeted primarily for research and educational use.
https://www.nsnam.org/
https://github.com/nsnam/ns-3.16-git
resources
installation
ns-3 installation
network topology
https://www.slideshare.net/rahulhada/building-topology-in-ns3
https://www.slideshare.net/rahulhada/building-complex-topology-using-ns3
python binding
https://www.nsnam.org/docs/manual/html/python.html
distributed simulation
https://www.nsnam.org/docs/models/html/distributed.html