AE	Autoencoder
CIFG	Coupled Input and Forget Gate
CL	Collaborative learning
CNN	Convolutional Neural Network
DNN	Deconvolutional Neural Network
DOSN	Decentralized Online Social Network
DP	Differential Privacy
DT	decision tree
FL	Federated learning
HFL	Hierarchical federated learning
IID	Independent and Identically Distributed
IoT	Internet of Things
LR	logistic regression
LSTM	Long Short-Term Memory
ML	Machine learning
MLP	Multilayer Perceptron
NN	Neural Network
OSN	Online Social Network
RF	random forest
RNN	Recurrent Neural Network
SLR	systematic literature review
SMS	systematic mapping study
TEE	Trusted execution environment