Aggregation at scale is even more complicated than just the number of devices. If you want the conversation to be bidirectional over the highly NAT-driven internet, you will probably want the connection to be persistent. This means you can poll or command a device from the server as well as have your device send requests to the server.  This is not directly similar to a web service model, which is based on many fast, transient connections.  Latency might also be a question for you, if you have human real time users.  We haven&#x27;t even spoken about sensor data streaming in from millions of devices while you&#x27;re trying to talk to them.  Then you get into availability and redundancy and other guarantees, it gets really interesting. Did I mention security (hello, Samsung?), unless you want miners and spambots running on all your devices, you&#x27;re now talking secure images and real crypto on a flyweight embedded device.<p>Yes, there are bigger real world issues for IoT than the protocol.