gRPC communicates via HTTP/2, implemented by a Netty server on the Content Server and Workflow Server. See Spring gRPC Server / Security / Netty for information on the configuration procedure for TLS or mTLS security. Mind that clients need to enable a corresponding configuration as well. Client properties spring.grpc.client.channels.cap.negotiation-type and spring.grpc.client.channels.wf.negotiation-type need to be adjusted accordingly.