The Azure IoT Hub is accessible using multiple protocols. You can useMQTT,AAMQP and HTTP. It’s even possible to run MQTT and AMQP over HTTP using web sockets (in case your firewall is closed).
This week, I had to connect a device to the IoT Hub running its own propriety runtime environment. The only way to communicate was HTTP.
Luckily, still HTTP is supported but communication works a bit different compared to using the IoT Hub SDK’s which Microsoft is offering.
Yes, at first it seems easy to just make a POST or GET to a REST endpoint. But looking at the security, just providing the Device connection string is not enough. You have to extract an SAS (Shared Access Signature) token first.