Experimenting with large-scale real world data is crucial for the development of network protocol and investigate their performance. However, collecting such data from real networks, and especially to annotate them with ground truth proves to, if not impossible, too tedious. In such cases use of simulated data, generated for various network scenarios, becomes a plausible alternative. To this purpose, we have developed a SIP network simulation system that employs probabilistic network model and we have demonstrated its use fort he performance analysis of statistical (D)DOS attack detectors.