node-red-contrib-azure-iot-hub-send-c2d is a node-red node that allows you to send cloud to device with Azure IoT Hub.
If you need nodes to receive messages or to send messages as a device, check out the package node-red-contrib-azure-iot-hub
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This node just connect to the IoT Hub and send the message to a specified device. The node will send msg.payload to the device with id as msg.deviceId.
You also need a connectionString, which is used to connect and authenticate to the IoT HUB. This value can be found in the Azure IoT portal. Go to services > shared access policies and pick one entry connection string (or create an entry). Be sure the entry has the serviceConnect permission.