With the rise in cyberattacks targeting modern networks, Intrusion Detection Systems (IDS) have become a critical component of cybersecurity. Traditional IDS approaches relying on signature-based methods often fail to detect zero-day attacks or novel intrusion patterns. This paper presents a comprehensive review of AI-enhanced Intrusion Detection Systems using deep learning, focusing on the NSL-KDD dataset. The study explores state-of-the-art architectures including Convolutional Neural Networks (CNN), Recurrent Neural Networks (RNN), Long Short-Term Memory (LSTM), Autoencoders, and hybrid deep learning approaches. Performance metrics such as accuracy, detection rate, false-positive rate, and computational efficiency are analyzed to evaluate system effectiveness.
Introduction
The NSL-KDD dataset is widely used as a benchmark for evaluating IDS models, and prior research has explored many deep learning approaches such as autoencoders, Deep Belief Networks, RNNs/LSTMs, CNNs, attention mechanisms, transformers, and hybrid models. These studies show that deep learning improves detection accuracy, feature learning, and ability to identify both known and unknown attacks, though challenges remain in computation cost, interpretability, and handling real-time traffic.
The proposed system in the text is an AI-enhanced hybrid IDS architecture combining CNN, LSTM, and attention mechanisms. CNN layers extract spatial features, LSTM models temporal patterns, and attention highlights important features, followed by fully connected layers for classification. This is designed to improve accuracy in detecting normal vs. malicious network activity.
The methodology describes a multi-layered system architecture:
A detection layer using containerized ML models (real-time traffic analysis)
A response layer using serverless functions for automated mitigation and alerts
A management layer for orchestration, scaling, and model updates
It also includes datasets like NSL-KDD, CICIDS2017, and UNSW-NB15, along with preprocessing steps such as normalization, feature selection, and encoding. The system uses a mix of ensemble ML models and deep learning for improved robustness.
Finally, the system emphasizes security and encryption, using TLS/mTLS for data-in-transit, AES-256 encryption for data-at-rest, and secure serverless practices to protect logs, models, and network traffic across cloud and Kubernetes environments.
Conclusion
AI-enhanced IDS using deep learning provides robust, scalable, and adaptive protection against modern cyber threats. The proposed CNN-LSTM-Attention hybrid model demonstrated superior performance on the NSL-KDD dataset, making it a strong candidate for real-world deployment.
References
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