Abstract:Machine Learning (ML) has become ubiquitous, and its deployment in Network Intrusion Detection Systems (NIDS) is inevitable due to its automated nature and high accuracy in processing and classifying large volumes of data. However, ML has been found to have several flaws, on top of them are adversarial attacks, which aim to trick ML models into producing faulty predictions. While most adversarial attack research focuses on computer vision datasets, recent studies have explored the practicality of such attacks against ML-based network security entities, especially NIDS. This paper presents two distinct contributions: a taxonomy of practicality issues associated with adversarial attacks against ML-based NIDS and an investigation of the impact of continuous training on adversarial attacks against NIDS. Our experiments indicate that continuous re-training, even without adversarial training, can reduce the effect of adversarial attacks. While adversarial attacks can harm ML-based NIDSs, our aim is to highlight that there is a significant gap between research and real-world practicality in this domain which requires attention.