OPNET based simulation modeling and analysis of DoS attack for digital substation

Due to DoS (Denial of Service) as the most serious cyber attack for digital substation, a modeling of data flow with different properties as periodic, random, sudden response is firstly introduced, followed by a simulation modeling of DoS attack based on the SYN-Flood principle; the module design and simulation implementation scheme based on OPNET platform has been proposed in detail. The simulation scenario is selected as the star network where the station layer server is under the SYNflood attack, and the case studies are made for wide-band of 10BaseT and 100BaseT data link. The simulation results give the performances of the station layer server before and after SYNflood attack, and the attack consequences are long stay at a high CPU utilization, time delay increasing of TCP connection, and the increasing of link throughput to exhaust the link band, etc. , in which the attempts of DoS are exposed to make the station layer server disable to response the normal business request, i. e. , to deny the service.