Emulator for testing the performance of framed access schemes

We present the architecture of an emulator, named FRACAS (FRAmed Channel Access Simulator) which is suitable for testing the performance of DA-TDMA access schemes. The main strengths of the FRACAS architecture are its speed, extendibility, and the existence of a working prototype whose portable source code is freely available to students and researchers in the field of framed allocation methods. FRACAS was designed to compare different satellite access schemes, in a quick and accurate way. Anyway, it can be employed for the performance evaluation of any TDMA access method. The modularity of FRACAS facilitates the inclusion of new features. FRACAS users can choose the network configuration, the whole traffic load of the network, the traffic load of each individual station, the request and the allocation policy, and the statistics to collect. The validation test of our implementation of FRACAS is presented, comparing the results with those obtained in the real experimentation.