Department of Computer EngineeringNetwork Simulators have been widely used in many uses of academic and educational areas. In advance of applying experimental simulation results to real world networks, it is important to verify their theoretical network performance and some of specific event routines through network simulators (ns-2, ns-3, OPNET, NetSim, etc.). If the test and verifying procedures are omitted, the system may cause some unexpected problems which can result in unreliability, unexpected maintenance costs and so on. Therefore, it is a common practice to demonstrate the performance of network prior to public release using software simulator. In this context, we focus on problems of the most renowned simulation package, ns-3. In the point of simulation development performance, the ns-3 uses some of unnecessary modules compared to a customized solution, in particular, for a small and simple network simulation. In this thesis, we define several problems and disadvantages of the ns-3, and present solutions and comparison results to solve high complexity problem of simulations and the accessibility of simulation source code to the beginners who are about to use the simulation for educational use: 1) we present a simple software development techniques which reduce the development times and the number of needless module in C++ objected-oriented programming environment; As the other way to implement a simple discrete network simulator, 2) we also present the simple network simulator development algorithm(SNSDA) that describes programming steps for discrete-event network simulator; Finally, we compare our simple development algorithm to the ns-3 in case of the most general IEEE 802.11 based wireless network scenario so that the SDA has some advantages in wireless network simulation.ope