This study examines a one-dimensional Convolutional Neural Network and a hybrid model, investigating how both architectures can detect network attacks in binary and multiclass classification settings, and provides actionable insights for practitioners choosing between deep learning and classical approaches under real-world NIDS deployment constraints.
Abstract
Digital infrastructures are growing rapidly and cyberattacks are becoming increasingly sophisticated. As a result, Network-based Intrusion Detection Systems have become a critical component of modern cybersecurity. Signature-based methods sometimes fail to detect new threats, where machine learning and deep learning can provide a valuable alternative. This study examines a one-dimensional Convolutional Neural Network and a hybrid model called CNN-BiLSTM, investigating how both architectures can detect network attacks in binary and multiclass classification settings. Both architectures were evaluated on the CIC-IDS2017 and UNSW-NB15 benchmark datasets through a rigorous experimental protocol incorporating stratified 5-fold cross-validation, Focal Loss, QuantileTransformer scaling, and SMOTE oversampling. Random Forest and XGBoost were additionally tested on UNSW-NB15 as classical baselines. The results show that CNN achieves near-perfect binary classification performance on CIC-IDS2017, with 99.75% accuracy and a ROC-AUC of 0.9999. CNN-BiLSTM reduces false negatives by approximately 36% in the binary UNSW-NB15 setting, albeit at the cost of 4–6 times higher inference latency. In multiclass classification, CNN outperforms CNN-BiLSTM on CIC-IDS2017 with a higher macro F1-Score (0.701 vs. 0.671). XGBoost achieves comparable F1 performance to deep learning models in significantly less training time, once again demonstrating the enduring value of ensemble methods. Minority attack class detection remains a fundamental unresolved challenge across all configurations, laying the groundwork for future research on class-wise threshold calibration and Transformer-based architectures. The findings provide actionable insights for practitioners choosing between deep learning and classical approaches under real-world NIDS deployment constraints.
The rapid growth of digital communication technologies, cloud computing, and Internet of Things (IoT) devices has
increased both the frequency and sophistication of cyber-attacks, making effective intrusion detection an essential component of
modern cybersecurity systems. Traditional signature-based intrusion detection systems (IDS) are effective against known attacks
but fail to detect previously unseen or evolving threats. This study investigates the application of deep learning models for binary
network intrusion detection using the NSL-KDD benchmark dataset. Three standalone architectures, Convolutional Neural
Networks (CNN), Long Short-Term Memory (LSTM) networks, and Deep Neural Networks (DNN), are implemented and
evaluated, alongside a CNN-LSTM Hybrid model that integrates spatial and sequential learning, and a DNN-LSTM Ensemble
model that combines independently trained DNN and LSTM predictions through weighted averaging. Following data cleaning,
categorical encoding, normalization, and Random Forest-based feature selection (41 features reduced to 20), all models were
trained and evaluated under identical conditions using Accuracy, Precision, Recall, F1-Score, ROC-AUC, training time, and
inference time. The standalone DNN model achieved the best overall performance, with 80.98% accuracy, 97.08% precision,
68.66% recall, 80.43% F1-score, and 96.11% ROC-AUC, while also requiring the shortest training time (39.69 s). The CNNLSTM Hybrid model attained the highest precision (97.23%) but did not outperform the standalone architectures overall, and
the DNN-LSTM Ensemble produced balanced but not superior results. These findings indicate that carefully designed
standalone architectures can match or exceed the performance of more complex hybrid and ensemble models for binary
intrusion detection, while incurring substantially lower computational cost. The study contributes a controlled, commonframework comparison of five deep learning architectures and provides practical guidance for selecting computationally
efficient models for anomaly-based intrusion detection.
Ketki Naik, Sanjeev Ghosh· International Journal for Re...· 0 citations
The findings indicate that hybrid deep learning techniques can improve network security by enhancing intrusion detection capability while reducing false alarms.
A. O. Jimoh-Mahmud, Abubakar Dayyabu, Abubakar Sadiq Idris et al.· FUDMA Journal of Sciences· 0 citations
Traditional Intrusion Detection Systems (IDSs) tend to have a high false positive detection rate, are time-consuming to train, and lack the flexibility to react quickly to changing cyber threats, such as Distributed Denial of Service (DDoS) attacks and phishing. Such restrictions decrease the responsiveness and reliability of the IDS services implemented in the university network, both wired and wireless, at the Uganda Christian University (UCU), where network and traffic analysis have become a necessity. This study analyzes the current threat environment of networking at UCU in terms of the type, origin, and target of various attacks to identify gaps in existing detection tools. To address data imbalance and high dimensionality, a range of machine learning algorithms was implemented and paired: Random Forest (RF), XGBoost, AdaBoost, Decision Trees, Convolutional Neural Networks (CNNs), and SMOTE. The highest performance was obtained by the combination of RF and SMOTE, with an accuracy of 81.88%, a precision of 82.17%, a recall of 81.88% and an F1-score of 80.19%. These ensemble learning methods can be effectively combined with oversampling to better detect minority attacks and minimize false alarms. This paper proposes an OFLN by addition of PSO to perform automated hyperparameter optimization and MAML to enable high-speed adaptation to new and previously seen attacks. The OFLN incorporates swarm-based optimization with meta-learning, attaining faster convergence, better generalization and efficiency. Empirical results show that OFLN is more effective than baseline ensemble models in detection accuracy, resistance to class imbalance and training efficiency, making it an innovative, scalable and practical IDS.
A deep learning-based intrusion detection framework that utilizes flow-level statistical features and a hybrid Convolutional Neural Network–Bidirectional Long Short-Term Memory (CNN–BiLSTM) architecture to capture both spatial and temporal characteristics of network traffic is proposed.
H. Hussein, Saad Raad, Ali Qasim· Al-Noor Journal of Engineeri...· 0 citations
Traditional rule-based intrusion detection systems generally fail in identifying unknown or evolving threats; thus, automated and adaptive kinds of methods are crucial. Deep learning models provide promising solutions, but many recent studies depend on hybrid architecture, which increase the computational cost and reduce deploying ability on real-time or resource-limited systems. In this paper, we present and test a standalone LSTM model for multiclass cyberattack detection based on a CIC_IoT_Dataset2023, a recent labeled dataset that mirrors the actual network environment containing 33 attack categories. The dataset was extremely imbalanced as benign traffic accounted for most of the classes. To detect such attacks, we used the Synthetic Minority Oversampling Technique (SMOTE) to increase the frequency of less common types of address. The pre-processed dataset was then employed to train four models (RNN, CNN, DNN and the proposed LSTM) for performance analysis with sequential data. The proposed LSTM model achieved an accuracy between 2% and 7%. LSTM had good detection for frequent attacks and slow-changing patterns, which shows its capacity in learning long-lasting dependencies. The results demonstrate that a simple, lightweight standalone LSTM model can be used for effective and realistic intrusion detection without the need for complex hybrid architecture.
Jawad Hussain Awan, Misbah Safdar, Muhammad Ayaz Shirazi et al.· Italian National Conference...· 0 citations