## Abbreviations  
The following abbreviations are used in this manuscript: \begin{tabular}{l l} AI & Artificial Intelligence \\ AMQP & Advanced Message Queuing Protocol \\ ANN & Artificial Neural Networks \\ ANOVA & Analysis of Variance \\ APTs & Advanced Persistent Threats \\ AUC & Area Under the Curve \\ CoAP & Constrained Application Protocol \\ DL & Deep Learning \\ DNN & Deep Neural Network \\ DoS & Denial of Service \\ DT & Decision Tree \\ DTC & Decision Tree Classifier \\ EDA & Exploratory Data Analysis \\ EL & Ensemble Learning \\ FN & False Negative \\ FP & False Positive \\ FPR & False Positive Rate \\ FS & Feature Selection \\ GB & Gradient Boosting \\ HTTP/HTTPS & Hypertext Transfer Protocol/Secure \\ IDS & Intrusion Detection System \\ IoT & Internet of Things \\ KNN & k-nearest Neighbor \\ LR & Logistic Regression \\ LR-DDoS & Low-Rate Distributed Denial of Service \\ MCC & Matthew's Correlation Coefficient \\ MitM & Man-in-The-Middle \\ ML & Machine Learning \\ MLP & Multilayer Perceptron \\ MQTT & Message Queuing Telemetry Transport \\ MQTTSA & MQTT Security Assistant \\ NB & Naive Bayes \\ NBC & Naive Bayes Classifier \\ OvR & One-vs.-Rest \\ PCC & Pearson Correlation Coefficient \\ ReLU & Rectified Linear Unit \\ RF & Random Forest \\ RNNs & Recurrent Neural Network \\ ROC & Receiver Operating Characteristic \\ SMDT & Statistical Moments Difference Thresholding \\ SSL & Secure Sockets Layer \\ SVM & Support Vector Machine \\ TLS & Transport Layer Security \\ TN & True Negative \\ TP & True Positive \\ TPR & True Positive Rate \\ XGBost & Extreme Gradient Boosting \\ \end{tabular}   
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