Federated learning (FL) is a machine learning technique that enables multiple decentralized organizations to train a model without exposing local data samples. Instead, during the training, lots of encrypted messages will be exchanged among the participants to aggregate the global model. Due to the message is so important and its requirements of real-time and sequential, it brings some challenges to the transmission. In this session, we will talk about how to address the above challenge with the Apache Pulsar project, and we will go through the details about how popular FL project FATE(https://github.com/FederatedAI/FATE) use Pulsar to do federated training.