I have used the pubsubclient library for Arduino for communicating with an MQTT broker in the past, however the library works only with Ethernet connecction. I need to use GSM in my application and am using the SIM900 at the moment. However, I cannot seem to find any library for MQTT communication using an Arduino as MQTT client and SIM900 as gateway. I found this to be surprising as there must surely be many instances where one would want to upload data from Arduino to a MQTT broker in a mobile scenario where cellular network is the only option (in place of Ethernet). So my questions are:
- Is it possible to use the Arduino as MQTT client and SIM900 as gateway for communicating with an MQTT broker? Are there any libraries for the same?
- What is the current standard way (gateway / communication protocol) of uploading some sensor data from Arduino to an internet server in a mobile scenario (i.e., where Ethernet is not an option)?