Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4519 SGB-IDS: A SWARM GRADIENT BOOSTING INTRUSION DETECTION SYSTEM USING HYBRID FEATURE SELECTION FOR ENHANCED NETWORK SECURITY VAHIDUDDIN SHARIFF1, NVS PAVAN KUMAR2, N ASHOKKUMAR3, SURESH KUMAR MANDALA4, MOHAN AJMEERA5, N S KOTI MANI KUMAR TIRUMANADHAM6*, P CHIRANJEEVI7 1,6Assistant Professor, Department of CSE, Sir C R Reddy College of Engineering, Eluru, Andhra Pradesh, India 2Assistant Professor, Department of CSE, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Andhra Pradesh, India 3Professor, Department of ECE, Mohan Babu University, Tirupati, Andra Pradesh, India 4Assistant Professor, Department of CS & AI, SR University, Warangal, Telangana, India 5Assistant Professor, Department of CSE, Chaitanya Bharathi Institute of Technology, Hyderabad, India 7Professor, Department of CSE, Amrita Sai Institute of Science and Technology, Bathinapadu, Paritala, India
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[email protected] ABSTRACT This paper proposes an integrated approach to build up IDS with proper effectiveness toward the rising need for strong network security. Network traffic anomaly detection and classification are one of the major aims and enhance the security layer against various types of cyber threats. This study is a methodical approach in which a diverse set of data is first extracted from Kaggle. The collected dataset is a comprehensive one that includes various kinds of network traffic data. The first step includes preprocessing the data, i.e., handling missing values, removing erroneous entries, and dealing with outliers using the Zscore method. To counter class imbalance, the Synthetic Minority Oversampling Technique (SMOTE) is utilized in generating synthetic samples in underrepresented classes for the generalization of models. The feature selection is done by using the Variance Mutual Forest (VMF) algorithm relies on the Variance Thresholding, Mutual Information, and Random Forest Selection methods. This method unites Variance Thresholding, to select statistically significant features with Mutual Information, and Random Forest for feature dimension reduction with the goal of overfitting minimization. For building models, a hybrid of Particle Swarm Optimization (PSO) and Light Gradient Boosting Machine (LightGBM), which is termed Swarm Gradient Boosting (SGB), is used. By using soft voting to aggregate the outputs of PSO and LightGBM, the proposed SGB model improves the prediction accuracy, the degree of robustness, and adaptability. The presented methodology has achieved high classification accuracy of 97.28%, precision of 93.49%, recall of 91.88%, F1 score of 94.23%, and low RMSE of 0.2592. These metrics demonstrate that the model is reliable and of practical use for intrusion detection in dynamic, high-dimensional environments of networks, providing a proper solution to modern security network challenges. Keywords: Intrusion Detection System, Network Security, SGB Model, PSO, LightGBM, Variance Mutual Forest (VMF), SMOTE, Z-score Method, Data Preprocessing. 1. INTRODUCTION An ID is that part of security technology important to detect and react to the possible threats coming in a network or a system. It identifies unusual patterns or behaviors which may suggest malicious activities through the analysis of network
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4520 and system activity. There are two types of IDS such as Network-based IDS (NIDS) and Host-based IDS (HIDS). NIDS is a network-wide monitoring traffic scanning for anomaly occurrence on numerous entry points whereas HIDS is host or endpoint-specific monitoring of internal logs and user's activities [1]. IDSs apply different detection techniques: they use signature-based and anomaly-based detection. Signature-based IDS compares seen activity with known threat patterns or "signatures." It is excellent at finding already-documented attacks [2]. It can have an issue with new or evolving attacks. In contrast, anomaly-based IDS uses machine learning and statistical analysis to produce a baseline of normal behaviour and marks any deviation from the baseline as a potential threat. This can be useful in detecting zero-day attacks, but at times, it is prone to false positives. While IDS is essentially a passive monitoring device, it is crucial to many modern cybersecurity frameworks. It provides key information on the vulnerabilities of the network and aids incident response because administrators are notified in realtime about any suspicious activities. However, while IDS detects attacks, IPS does not only detect but also actively prevents any harmful attack [3]. IDS is often integrated with other security tools, such as firewalls, to enhance the improvement of network defence. In the current cyber threat era, IDS technology is still for organizations to protect sensitive data and maintain secure network environments. It detects actual or potential intrusions in real-time and thus aids in proactive threat mitigation by protecting valuable resources and maintaining the trust level in digital systems. 1.1. Research Gap Although there have been many significant advances in IDSs through machine learning techniques, many gaps still exist. For instance, while Kumar et al. 2020 proved the efficiency of PCA-KNN on the KDD-99 dataset, their method is mainly limited to traditional datasets and does not involve or cover the real nature of modern network traffic as well as complex attack techniques. Sarkar et al. in 2022 addressed class imbalance and rare attacks using an ensemble approach but do not probe the scalability and real-time applicability of their designed model in high-traffic environments. Hyperparameter tuning under dynamic network conditions has also remained an under-explored area. Srinivas et al. (2022) described the deep learning potential of DNN in IDS models but failed to address the computational complexity or latency issues that would pose obstacles to real-time deployment, especially in large-scale networks. Bose et al. (2024) has forwarded the BATMC model for IDS in SDN from BiLSTM and attention mechanisms. This approach holds promise; however, its scalability and adaptability in realworld SDN environments remains to be exhaustively tested and the detection of hybrid attacks-combining traditional and advanced techniques-is an unexplored research area. These gaps indicate that further research has to be done to enhance the scalability, real-time performance, and robustness of IDS models to handle evolving and hybrid attack scenarios in diverse network environments. 1.2. Research Questions RQ.1 In what ways the IDS models learn to adapt to emerging and evolving network traffic patterns and emerging attack strategies than traditional dataset like KDD-99? RQ.2 What are the appropriate ways to scale and to deploy machine learning IDS models in real-time, particular for high-traffic or dynamic network environments? RQ.3 How to tune the hyper parameters to be optimized IDS models' accuracy and performance for various network scenarios and a wide range of different attack vectors? 1.3. Hypothesis The hybrid SGB model with VMF feature selection will outperform existing IDS techniques in accuracy and adaptability to dynamic network conditions. 1.4. Contributions Improved Data Preprocessing: The research work depicts better technique data preprocessing by taking care of missing values, errors and outliers. Outliers are dealt with by application of Interquartile Range method for the detection of outliers. To address the class imbalance problem in the dataset under study, Synthetic Minority Oversampling Technique is applied. This allows for improved detection of rare types of attacks since synthetic data may be generated for the underrepresented classes. Better Feature Selection (VMF): VMF allows introducing a feature selection technique using a combination between the Chi-Square test and Lasso regularization to finish with much better reduced feature representation for removing out unnecessary features and reducing overfitting, and that makes it efficient by considering only relevant data. Hybrid SGB Model: The proposed hybrid model is SGB, with the strengths of PSO as well
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4521 as LightGBM so as to get better prediction precision. The soft voting algorithm is effectively used by SGB, which shows better and almost accurate results with noisy and complex network data. Scalability and Real-World Adaptability: The proposed method is supposed to scale and adapt real-world networks; hence, it would be friendly with large, high-traffic environments. This is because, with the integration of advanced machine learning techniques, it can adapt dynamically to network traffic and continually check a wide variety of attacks in real-time; hence, it is very applicable for modern needs in network security. 2. LITERATURE REVIEW Kumar et al. [4], in 2020 proposed an IDS based on supervised machine learning techniques that can recognize normal and malicious data packets to improve the security of a network. Because data exchange across networks is a necessity in this modern world, safety during information conveyance between these connections has become very vital due to the threat of internal and external attackers. Kumar et al. utilized the KDD-99 dataset, which is known to be one of the benchmarks for research in IDS; it has 32,640 samples, of which 12,440 are classified as normal and 20,200 as attack samples. It had a balanced training set compared to the test set. The work used, with SVM and KNN classifiers during supervised learning, PCA for dimension reduction to filter data and to optimize the efficiency of the classifier. Among the models tested, the approach PCA-KNN had the highest accuracy of 90.07% using a cosine distance metric and a principal component (pc) value of 5. The results yield an example of how dimensionality reduction techniques can improve the effectiveness of supervised machine learning models for IDS: PCA and KNN are thus combined to indicate a highly accurate solution for differentiating normal and attack data packets in network traffic. In 2022, Sarkar et al. [5], introduced an advanced machine learning ensemble technique for improving the detection accuracy as well as the efficiency of network intrusion detection systems (IDS). The work seemed to be focused on the importance of tuning hyperparameters and data preprocessing in improving the capabilities of detection, especially for the detection of rare types of attacks, which are usually difficult to identify like root-to-local (R2L) and Root (U2R) attacks. The rebalancing process was performed on the widely used KDD Cup99 and NSL-KDD datasets, as class imbalance-a prevalent problem in intrusion detection-was handled by data augmentation. The architecture of cascaded, meta-specialized classifiers made up of MLPs will face different layers trained to classify specific attack classes, enhanced classification precision as well as reduced false positives. They optimized their methodology and obtained detection accuracy of 89.32% and FPR as 1.95% on one dataset, while an accuracy of 87.63% with the corresponding FPR of 1.68% on the NSL-KDD dataset. By assigning higher weights to the best performance algorithms, this ensemble method markedly enhanced detection performance and presented potential use for hyperparameteroptimized ensemble techniques to build more reliable and accurate IDS compared with traditional models. In 2022, Srinivas et al. [6], proposed a new machine learning-inspired algorithm for real-time network intrusion detection problems. The attacks are constantly evolving, and traditional IDS generally fails to realize sophisticated attacks in real-time, mainly due to their lack of generalization across types of attacks. There are many algorithms for machine learning such as the Decision Trees, Random Forests, Support Vector Machines (SVM), K-Nearest Neighbors (KNN), and even the deep neural networks (DNN) that have promised much in terms of classification and predicting network intrusions. In their research study, Srinivas et al. considered applying a number of ML models that included Logistic Regression, Naïve Bayes, Decision Trees, and DNN with high-dimensional datasets. Their testing results revealed that these types of models like Random Forest and Decision Trees were giving more than 92% accuracy, along with the high precision and recall values. In the case of deep learning models, the DNN which has multilayered results showed a very outstanding result-the five-layer DNN obtained 95.5% F1 score with an accuracy of 93.2%. The study proved quite significant on aspects of employing the integration of different machine learning techniques to identify known and unknown attacks in real time. What the results indicate here is that the integration of traditional ML algorithms with deep learning models can effectively enhance the effectiveness of IDS and make it more efficient in addressing complex, dynamic network traffic. The researchers from Bose et al. [7] suggest a robust multi-layered security framework for IDS in the SDN environment to target adaptable and scalable security by 2024. IDS has traditional models with issues related to accuracy and
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4522 scalability problems due to the complexity of SDN traffic and its continuously changing nature. Generally, datasets of NSL-KDD were tested in general. For such problems, the authors presented a model known as BAT-MC that integrates Bidirectional Long Short-Term Memory networks along with an attention mechanism and multiple convolutional layers for context processing in both directions without requiring any hand-crafted feature engineering. Therefore, this approach has optimized the traffic analysis in SDN infrastructures for finding the subtle anomalies in real time. In this scenario, it was demonstrated, based on the In-SDN dataset-by Bose et al. specifically designed to cover all those diverse intrusion types and traffic patterns within an SDNthat has substantial gains in performance. When incorporated with ensemble methods, BAT-MC reached 86% accuracy rate, which points to excellent prospects for high-definition anomaly detection and high scalability. This work highlights how deep learning techniques, namely BiLSTM combined with attention layers, may be utilized in IDSs, thereby representing a promising solution to overcome the complex security demands of dynamic SDN environments. 3. PROPOSED METHODOLOGY Dataset acquisition, data preprocessing, feature selection, and model building are incorporated in this four-phase design methodology to design shown in Fig.1 is an efficient intrusion detection system. After acquiring the dataset from Kaggle, it contains some diverse types of network traffic data. Data preprocessing includes missing value management, erroneous entries, and outliers’ removal using Z-score method, so they may have minimal effects on the resultant output from the model. Class balancing SMOTE [8] is the algorithm used to over-sample the lesser represented class to create synthetic samples that enhance the model generalization capability. For feature selection, Variance Mutual Forest (VMF) will be applied using a hybrid feature selector with the combination of Variance Thresholding [9], Mutual Information [10], and Random Forest [11] to select the most representative features. This detects the presence of features that carry statistical significance towards class labels. A hybrid model based on Swarm Gradient Boosting (SGB) is used for model development. This model integrates the margin-based approach of PSO [12] with the flexibility of LightGBM [13] and its instance-based method. Soft voting in such cases produces wellbalanced and accurate predictions by averaging the output, which makes SGB more resilient and adaptive to noisy and high-dimensional data environments commonly met in network intrusion detection scenarios. Figure 1: Proposed Methodology Workflow 3.1. Data Collection The dataset for this analysis is obtained from a highly comprehensive cybersecurity dataset published on Kaggle, tracking extensive parameters of network and session-specific parameters. This record captures characteristics like session durations (dur), the type of protocol used (proto), and the type of service (service) besides packet level details about sent and received packets (spkts, dpkts), as well as data volumes in sbytes and dbytes. Such metrics as session load (sload, dload), packet rates (rate), and TCP-related fields tend to help better discern and notice the network behavior anomalies. Another important field is the information about the session states (state), Timeto-Live values (sttl, dttl), and further session properties which are quite crucial for distinguishing normal and suspicious network traffic. Attack categories (attack_cat) and binary labels (label) mark instances of known intrusions, therefore this dataset fits well into developing supervised learning models. Detail and the label attack instances in the dataset are an excellent foundation for training and validation of IDS models, which enable high classification accuracy in potentially intruding network environments. 3.2. Data Cleaning At this data-cleaning stage, the dataset was checked and prepared for further analysis. Records: 175,341 Attributes: 45 Each feature is explored to be complete and correct. Preliminary checks confirmed that there are no missing values across any column of the data set, so no data imputation or row removal is required before analysis. This
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4523 dataset consists of integers, floats, and categorical objects. Thus, all the attributes, such as packet counts (spkts, dpkts) and session metrics (dur, rate), are verified against the expected value. This also ensures that the integrity and compatibility of the data type stay good with the algorithms used during machine learning. The fields like proto and attack_cat were kept in their object types in order for smooth encoding at a later stage. This clean, verified dataset ensures that any subsequent analysis and model training will be done based on reliable data of high quality, thus serving to further enable accurate insight in intrusion detection task results. 3.3.1. Handling Imbalnced Dataset Handling imbalanced datasets is a common issue in machine learning. Models favor the majority class because they do not perform that well on the minority class. The Synthetic Minority Oversampling Technique, SMOTE, is one of the popular methods used for solving this problem. SMOTE [14] generates synthetic instances of the minority class instead of duplicating existing samples. It picks a sample from the minority class, then identifies its k-nearest neighbors and creates synthetic samples through interpolation in the space between that sample and its own k-nearest neighbors. Its increase in minority-class representation gives a model more robust patterns to learn. Synthetic data points generated prevent overfitting in duplicating samples. While effective, SMOTE may introduce noise if the synthetic samples are created in regions with overlapping classes or in sparse areas shown in Fig.2. However, if SMOTE is applied correctly, then the overall performance of the model improves, especially in imbalanced classification problems, and ensures that, both majority and minority classes, have a fair share of representations. Figure 2: Before and After applying SMOTE 3.3.2. Handling Outliers Using Z-Score Outliers are extreme values that differ significantly from the rest of the data and can distort statistical analysis and machine learning model performance. One common method to handle outliers is the Z-score [15], which measures how far a data point is from the mean in terms of standard deviations. It is calculated using the formula: (X−μ)/σ, where is the data point, μ is the mean, and σ is the standard deviation. A Z-score of 3 or higher (or -3 or lower) typically indicates that a data point is an outlier, as it lies far from the mean. The Z-score method is effective for normally distributed data because it assumes that most values lie within a few standard deviations of the mean. Once outliers are identified by Z-scores, they may be discarded, capped, or substituted with more plausible values so that they don't unreasonably skew the model. The approach to dealing with it relies on the context and how important the data in question are. Thus, outliers are valuable information as well and their elimination may reveal precious conclusions depicted in Fig.3. Hence, the outliers must be handled with great care so that it does not lose data integrity.
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4524 Figure.3 Handling Outlier Using Before and After Applying Z-Score 3.3. Feature Selection using VMF Variance Mutual Forest (VMF) is a hybrid feature selection and classification algorithm that integrates three robust methods: Variance Thresholding, Mutual Information, and Random Forest. The integration utilizes the strengths of each approach to improve the accuracy and interpretability of machine learning models, particularly for feature selection and classification tasks. The major objective of VMF is to enhance model performance by detecting and choosing the most significant features prior to using a Random Forest classifier, which is renowned for its strength and capability to manage complex data. Coupled together, VMF leverages the efficacy of these methods to make better predictions and better model interpretability. It is especially helpful in areas with high-dimensional data sets, where the choice of appropriate features is vital to obtaining the best results. 3.3.1. Variance Thresholding Variance Thresholding is a simple feature elimination method used to eliminate features with little or no variance over the dataset. The underlying premise here is that those features with minimum variation contribute minimal predictive power since they cannot differentiate between various points of data. Eliminating them decreases the dataset's dimension, which can increase model efficiency, minimize overfitting, and enhance computational speed. For a given feature 𝑥 the variance σ2𝑥 is calculated as the mean of the squared differences between the feature values and its mean shown in Equation (1): σ(𝑥)= ∑(𝑥 − 𝜇) (1) where: 𝑥 is the value of feature ii in the j-th data sample, 𝜇 is the mean of feature xii, n is the total number of samples in the dataset. The thresholding step involves removing features whose variance falls below a predefined threshold t. The condition for removing a feature represented in Equation (2): 𝐼𝑓 σ(𝑥)< 𝑡,𝑡ℎ𝑒𝑛 𝑟𝑒𝑚𝑜𝑣𝑒 𝑓𝑒𝑎𝑡𝑢𝑟𝑒 𝑥 (2) Here, t is a hyperparameter that can be adjusted depending on the dataset's characteristics or domain-specific requirements. Features with low variance, such as those with constant values or those providing little differentiation, are eliminated. 3.3.2. Mutual Information Mutual Information (MI) [16] is a statistical quantification of how much information one feature holds regarding another. MI measures the strength of the association between two variables and is best suited for finding dependencies between the features and target variable. Large MI values imply that the feature has a good association with the target and, therefore, it is more useful for the prediction model. in machine learning, MI is employed to decide the amount of information a feature (or set of features) conveys about the target variable and to assist in choosing the most important features for model training. Mutual Information between two variables X and Y is defined in Equation (3): 𝐼(𝑋;𝑌)= ∑ ∑ 𝑝(𝑥,𝑦)log (,) ()() ∈∈ (3) where: I(X;Y) is the mutual information between variables X and Y, p(x,y is the joint probability distribution of X and Y, p(x) and p(y) are the marginal probability distributions of X and Y, respectively. This equation basically calculates the demarcation between the joint distribution p(x,y) and the product of the marginal distributions p(x)p(y). For instance, if X and Y are independent, this means their mutual information I(X;Y) = 0, which means they carry no information in common. In contrast, the greater the mutual information, the stronger the dependency between the variables.
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4525 3.3.3. Random Forest Random Forest [17] is a very powerful ensemble learning algorithm for supervised classification and regression tasks. It does this by constructing many different decision trees while learning and combining their outputs to obtain better prediction performance. In the main, the algorithm uses bagging, or Bootstrap Aggregating, to generate random subsets of the data and features while training each individual tree-this reduces variance and prevents overfitting. By using Gini Impurity or Entropy, the data at the nodes of which each tree is based is actually split according to criteria that optimise the homogeneity of the subsamples. In classification, results from all trees are safely put together through majority voting while in the regression, predictions are averaged. Random Forest also gives some insights into feature importance based on how often and how well each feature does at splitting decisions across the forest. Good resistant to overfitting, handing missing values, and hardly affected by highdimensional datasets would make it highly flexible. Non-linear modeling capacity, the ability to work on datasets containing too many samples, made it a widely applicable algorithm in medical science, finance, and ecology. While many other algorithms suffered simplistics but consistent mediocre performance, Random Forest found out a way to balance simplicity and adequate performance. As such, it is perceived not only as a workhorse but also as a standard algorithm in modern machine learning [18]. Table 1: Variance Mutual Forest (VMF) Algorithm: Variance Mutual Forest (VMF) Input: Dataset D with features X and target variable y Output: Selected feature subset 𝑋 1. Preprocessing: Load dataset D Handle missing values Encode categorical variables if necessary 2. Step 1: Variance Thresholding Compute variance for each feature in X Remove features with variance below a predefined threshold θ Output reduced feature set X′ 3. Step 2: Mutual Information Filtering Compute Mutual Information (MI) between each feature in Xand target y Rank features based on MI score Select top k features based on a predefined MI threshold γ Output further reduced feature set X′ 4. Step 3: Random Forest-Based Feature Importance Train a Random Forest classifier on Xand y Compute feature importance scores Select the top mmm most important features Output final selected feature set X 5. Return 𝑋 for further model training. 3.4. Model Building using Swarm Gradient Boosting (SGB) Swarm Gradient Boosting [19], or SGB, is a hybrid model that combines particle swarm optimization with LightGBM to improve machine learning performance for large-scale tasks. Initialization of being, based on the social behavior of particles, is used to characterize an optimization algorithm where each particle corresponds to a particular solution. PSO updates its world through the best known position for each particle and the global best, enabling it to perform highly efficient searches for optimal solutions in complex hyperparameter spaces. The speedy and scalable gradient-boosting framework LightGBM is known for its efficiency with large datasets, using histogram-based techniques and leaf-wise growth strategies for quick and accurate computations. By combining the two, SGB improves LightGBM hyperparameters, thus improving accuracy while reducing overfitting and computational time. PSO has powerful capabilities for global search and helps update and fine-tune the LightGBM model, thus assuring better performance and scalability. Such an integrated approach, therefore, makes SGB a very good strategy for any complex large-scale data analysis task with enhanced prediction and computation time. 3.4.1. Particle Swarm Optimization Particle Swarm Optimization (PSO) is a nature-inspired optimization algorithm of social behavior of particles. It was first introduced by Kennedy and Eberhart in 1995 and modeled after
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4526 the movement of a flock of birds or a school of fish. The PSO algorithm involves a swarm of candidate solutions, referred to as "particles," moving in a multi-dimensional search space to find the optimum solution for a given problem. Each particle adjusts its position based on two historically defined positions, that is, its own best-known position and the best-known position for the entire population or swarm. These positions are updated through a velocity equation, using random coefficients to adjust the velocities and inject further volatility into the system, as such allowing the swarm to move itself out of local optima. Mathematically, the update for each particle's position and velocity is shown in Equation (4): v(t+1)= wv(t)+ crpbest− x(t) + crgbest − x(t) x(t+1)= x(t)+v(t+1) (4) where: v is the velocity of particle i x is the position of particle i pbest is the best-known position of particle i gbest is the global best position www is the inertia weight c,c are the cognitive and social coefficients r,r are random numbers between 0 and 1 Another advantage of PSO in machine learning models is its ability to search the large hyperparameter spaces in a timely manner and with good effectiveness. 3.4.2. Light Gradient Boosting Machine LightGBM stands for Light Gradient Boosting Machine, which is a high-performance, distributed gradient boosting framework developed by Microsoft for speed and efficiency optimization, especially for large datasets. It is a tree-based model that uses gradient-boosting techniques for the construction of predictive models. Unlike classical methods of gradient boosting, LightGBM is based on a histogram and its tree grows leaf-wise rather than in level-wise fashion, making the algorithm faster when applied to large amounts of data. In LightGBM, the core idea is to replace the real-valued features with histograms, which results in reduced memory consumption and faster training. The trees are grown in a leaf-wise manner such that at each iteration, the leaf with the greatest delta loss will be chosen to grow, instead of the more traditional level-wise techniques of growth. As a result, less number of trees is required to build a more accurate model and hence faster computation. Mathematically, LightGBM uses the following key steps in training: 1. Compute the gradient for each instance represented in Equation (5): g= () (5) where L is the loss function and is the prediction for instance i. 2. Split the data into bins based on feature values to form histograms. 3. Build trees using these histograms and calculate the optimal split using the following objective function represented in Equation (6): Objective = ∑ (6) Where gis the gradient, his the hessian, and λ is a regularization parameter. By using histograms and optimizing the leafwise structure, LightGBM achieves high speed, scalability, and predictive performance, making it ideal for large-scale datasets. Table 2: Swarm Gradient Boosting (SGB) Algorithm: Swarm Gradient Boosting (SGB) 1. Initialize the swarm: Create a population of particles. Set the initial positions and velocities of the particles randomly. 2. Initialize the Gradient Boosting model: Choose a weak learner. Set up the boosting algorithm. 3. For each generation (1 to 𝒎𝒂𝒙𝒈𝒆𝒏𝒆𝒓𝒂𝒕𝒊𝒐𝒏𝒔): For each particle in the swarm: Set the Gradient Boosting model's hyperparameters to the current particle's position. Train the Gradient Boosting model on the training dataset. Evaluate the model's performance using a validation set. Store the fitness value of the particle. Update particle velocity and position: Update each particle's velocity based on: Previous velocity Distance to its own best position Distance to the global best particle's position Update the particle's position by adding the new velocity. Update global best: If a particle has better fitness than the global best, update the global best with the particle's position. 4. Train the final Gradient Boosting model using the global best particle's hyperparameters. 5. Return the final trained Swarm Gradient Boosting model. 4. RESULTS AND DISCUSSION 4.1. Feature Selection Using VMF Feature selection is a vital preprocessing step in machine learning, aimed at enhancing model performance by identifying the most impactful predictors while reducing dimensionality and computational complexity. This process ranked
Journal of Theoretical and Applied Information Technology 15th June 2025. Vol.103. No.11 © Little Lion Scientific ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195 4527 features by their importance scores, with the top five being attack_cat (0.563707), id (0.249406), sttl (0.133706), sbytes (0.028829), and dbytes (0.024352) shown in Table.1 and Fig.4. The feature attack_cat emerged as the most significant, accounting for over 56% of the total importance. It plays a crucial role in distinguishing categorical variations that strongly influence the model’s predictions. id, the second most important feature, contributes significantly by potentially capturing unique patterns or identifiers relevant to the dataset. With a moderate scaling factor, Sttlolt reflects the temporal characteristics. Sbytes and Dbytes may be more useful in judging the data volume originating from, and directed to, the source or destination, respectively, and in consideration of these attributes, the dimensionality of the dataset is considerably reduced without compromising its predictive power, allowing efficient interpretive and robust models. Thus, these findings reiterate the need for targeted feature selection to improve model performance and computational efficiency. Future efforts will be focused on validation, domain-specific analyses, and feature engineering to ensure the selected features yield useful and meaningful insights. Table 3: Selected Features of VMF Feature Score attack_cat 0.564 id 0.249 sttl 0.134 sbytes 0.029 dbytes 0.024 Figure 4: Visualization for Selected Features using VMF 4.2. Model Building Using Swarm Gradient Boosting (SGB) The model developed out of a combination of Particle Swarm Optimization (PSO) and LightGBM (LightBoost) displays amazing performance, being able to exploit the advantages in both methods. A population-based optimization technique, PSO, has been applied in tuning the hyperparameters of the LightGBM model; thus, the algorithm has the capacity to explore for a set of best parameters that maximizes predictive accuracy class. This hybrid method significantly enhanced the model's performance, assuring efficient and accurate results. LightGBM [19], with its well-known scalability and speed, managed to process large datasets with minimal costs. Table 4: Performance Metric of SGB Performance Metric Value Accuracy 0.9728 Precision 0.9349 Recall 0.9188 F1 Score 0.9423 The performance metrics reveal the model's strength and effectiveness for practical applications. Achieving an accuracy rate of 97.28%, the model successfully classifies most instances, indicating a significant level of reliability. The precision and recall values 93.49% and 91.88%, respectively indicate that the model is not only accurate but also highly effective in identifying relevant positive instances shown in Table.2 and Fig.5. The F1 score of 94.23% confirms that the model strikes a strong balance between precision and recall, which is critical in tasks where both false positives and false negatives are costly. Furthermore, the low RMSE of 0.2592 suggests minimal error in predictions. Overall, the SGB model proves to be a powerful tool for high-accuracy predictions in complex datasets.