Dear Kwame,

Have you tried Packet Tracer from Cisco? 

Please see some of the links that I am attaching here.

http://www.monitortools.com/traffic/

https://en.wikipedia.org/wiki/Network_traffic_measurement

I think packet tracer 

Packet Tracer,GNS3, or Opnet. Opnet is much academic

Indeed, GNS3 could be a good choice as well. Here are some links I think might be useful.

http://resources.intenseschool.com/network-simulation-packet-tracer-or-gns3/

http://www.packettracernetwork.com/features/packettracer-vs-gns3.html

Good luck!

Greeting!