SW2PSA
SW2PSA (Stop & Wait and Sliding Window Protocol Simulator and Animator
...The aim of SW2PSA is to be used as a tool to support the animation of this protocols in a course like data networks, communication protocols or other related, and to include in the course a project that involves the programming of any of these protocols using a very known language as Java.
Since it is an open source program also helps the student who wishes to know the structure of a simple discrete event network simulator.