A new educational simulation tool designed for the generic study of wireless networks, the Wireless Fidelity Simulator (WiFiSim), is presented in this paper. The goal of this work was to create and implement a didactic tool to improve the teaching and learning of computer networks by means of two complementary strategies: simulating the behavior and performance of communication protocols based on the IEEE 802.11 standard widely studied in networking courses, and providing with improved scope and realism for students engaged in wireless network design and modeling. The educational interest of this tool lies in the realism of the simulation, which provides a high level of interactivity and visual information through a highly configurable graphic user interface, as well as highly intuitive and easy-to-interpret graphic results. This educational tool was tested by computer networking teachers, students, and professionals. The experience demonstrated the effectiveness of the software and resulted in a significant improvement in the students' practical work, leading to enhanced learning and consolidation of theoretical concepts. © 1963-2012 IEEE.