With the development of network application

network traffic is constantly increasing

and the web application testing is becoming more important.According to statistical results

the network traffic is self-similar in the time scale.Therefore

the research of self-similar traffic model is very important.Network traffic simulation has limitation by single computer.So this paper improves the Fraction Gaussian Noise (FGN) model so that it becomes a high-speed parallel algorithm to generate self-similar traffic.Using the improved algorithm

we propose a distributed system and present the design and implementation of this system.The paper also includes the work of achieving a network traffic detection tool.The results show that the testing samples generated by the distributed system have self-similar property.