Remote NAT Detect Algorithm Based on Support Vector Machine
Rui Li, Hongliang Zhu, Yang Xin, Yixian Yang, Cong Wang · 2009
The Network Address Translation (NAT) technique resolved the IPv4 address shortage problem effectively. Meanwhile, it brings issues to network management. Unauthorized NAT devices may be a significant security problem. Attackers may conduct malicious activities by using computers hidden behind unauthorized NAT. The remote NAT detect algorithm is proposed based on support vector machine method. Different from previous researches, it dose not depend on any special field in any packet. The network traffic is represented by 8 features and filtered by activity value which is calculated by the proposed function. Then, the support vector machine method is applied to analyze the feature vectors and tell which ones are from hosts behind NAT. The implementation shows that the accuracy and specificity of the algorithm is much higher when there are more hosts behind the NAT device.