I. Introduction
In conventional edge networks, there exists massive data produced at edge terminals deployed around the world, which presents a huge challenge in the management of these large amounts of data such as how to accomplish data transmission and processing as soon as possible while maintaining the data security [1]. To overcome this challenge, the Federated Learning (FL) model has been introduced [2], which is well-known for its two distinguishing features. First, as demonstrated in Fig. 1, unlike the traditional machine learning model requiring gathering data from edge terminals and then introducing considerable communication overhead [3], [4], [5], Local training can be performed in the FL framework in order to make full use of the computing capability in edge devices. Secondly, only the trained model parameters, instead of the original data, should be transmitted from edge devices to the center server for model aggregation thus considerably reducing the amount of transmitted data.
The edge networks.