Feature Selection Method based on Chaotic Salp Swarm Algorithm and Extreme Learning Machine for Network Intrusion Detection Systems

Abstract

Network Intrusion Detection Systems (IDSs) have been widely used to monitor and manage network connections and prevent unauthorized connections. Machine learning models have been utilized to classify the connections into normal connections or attack connections based on the users' behavior. One of the most common issues facing the IDSs is the detection system's low classification accuracy and high dimensionality in the feature selection process. However, the feature selection methods are usually used to decrease the datasets' redundancy and enhance the classification performance. In this paper, a Chaotic Salp Swarm Algorithm (CSSA) was integrated with the Extreme Learning Machine (ELM) classifier to select the most relevant subset of features and decrease the dimensionality of a dataset. Each Salp in the population was represented in a binary form, where 1 represented a selected feature, while 0 represented a removed feature. The proposed feature selection algorithm was evaluated based on NSL-KDD dataset, which consists of 41 features. The results were compared with others and have shown that the proposed algorithm succeeded in achieving classification accuracy up to 97.814% and minimized the number of selected features.