Hybrid Machine Learning-Based Approaches for Feature and Overfitting Reduction to Model Intrusion Patterns

Abstract

An intrusion detection system (IDS), whether as a device or software-based agent, plays a significant role in networks and systems security by continuously monitoring traffic behaviour to detect malicious activities. The literature includes IDSs that leverage models trained to detect known attack behaviours. However, such models suffer from low accuracy or high overfitting. This work aims to enhance the performance of the IDS by making a model based on the observed traffic via applying different single and ensemble classifiers and lowering the classifier’s overfitting on a reduced set of features. We implement various feature reduction techniques, including Linear Regression, LASSO, Random Forest, Boruta, and autoencoders on the CSE-CIC-IDS2018 dataset to provide a training set for classifiers, including Decision Tree, Naïve Bayes, neural networks, Random Forest, and XGBoost. Our experiments show that the Decision Tree classifier on autoencoders-based reduced sets of features yields the lowest overfitting among other combinations.