Aiming at the problem that System Wide Information Management (SWIM) system is affected by Distributed Denial of Service (DDoS) attacks in the application layer, a detection approach of SWIM application layer DDoS attack based on Hidden Semi-Markov Model (HSMM) was proposed. Firstly, an improved forward-backward algorithm was adopted, and HSMM was used to establish dynamic anomaly detection model to dynamically track the browsing behaviors of normal SWIM users. Then, normal detection interval was obtained by learning and predicting normal SWIM user behaviors. Finally, access packet size and request time interval were extracted as features for modeling, and the model was trained to realize anomaly detection. The experimental results show that the detection rate of the proposed approach is 99.95% and 91.89% in the case of attack 1 and attack 2 respectively. Compared with the HSMM constructed by fast forward-backward algorithm, the detection rate is improved by 0.9%. It can be seen that the proposed approach can effectively detect the application layer DDoS attacks of SWIM system.
To the shortage of theoretical support in the policy-making process of traffic guidance management, the research method of choice behavior with confinement mechanism of traffic information was proposed. From the perspective of human perception, the deep analysis of Multi-Source Traffic Information (MSTI) constraint rule was presented based on fuzzy clustering algorithm, then the road network environment was simulated by VISSIM and the traffic state pattern recognition model was established to simulate the mental activity of traveler under restriction of information. Then by means of Biogeme software, the choice model was constructed based on the behavior survey data, which was obtained in the road network example by using Stated Preference (SP) investigate method. Results show that the sanction of traffic information on travel behavior is very limited and the travelers prefer the preference path when traffic of this preference path is not very heavy, while this sanction enhances gradually and the path change behavior, which is influenced by the information, becomes more frequent when the preference path is more congested. The conclusions provided a new idea and reference for incomplete rational behavior research under the information environment, and also provided decision support for traffic management department.