SignalR

FCM Is a Wake-Up Path, Not a Real-Time Transport

FCM Is a Wake-Up Path, Not a Real-Time Transport A mobile application can maintain a WebSocket while it is active and still need Firebase Cloud Messaging when the operating system suspends it. Those mechanisms solve different failure conditions. WebSocket, MQTT, and SignalR assume that a client can participate in a live communication session. FCM is useful precisely when that assumption no longer holds: the application may be backgrounded, its process may not be running, or its persistent connection may have disappeared.