Streamline architecture of network simulator to facilitate teaching of computer networking

Many higher education programs contain the subject of computer networking. Enabling students to understand communication protocols in computer networks is a fundamental objective and challenge at the meantime in teaching computer networking. Simply explaining the protocols as a set of rules with syntax and semantics has been proved ineffective; utilizing real network devices incurs high cost. Consequently, simulation tools are widely used in teaching computer networking to support students' experimental learning. Some well-known network simulators are available over Internet, and some tools specifically designed for education purpose have been developed; however, the vertical integrated architecture of such simulators makes students have to spend much time and energy to learn the tools first. In this paper, we propose to separate the develop plane and operation plane of the simulator to facilitate the usage of simulation tools in teaching computer networking. To prove our concept, we develop a generic simulation framework FlexNtwk, which is compatible with the widely used network simulator ns-2. We apply the streamlined ns-2 simulator to our teaching in the past four years, and the feedback statistics from students show that the streamlined simulator is effective assisting students to understand communication protocols of computer networks.