Lets ask few questions that will help us the need for specific protocol for our solution:

• Does your IoT device work on request and response architecture? This question defines the one way or bidirectional communication is required or not for your solution.

HTTPs would be a good protocol to implement your IoT solution

• Does your IoT device need to run a long active process? It means the connected operation that you want to automate will need more time to finish.

HTTPs would be a good protocol to implement your IoT solution

• Does your IoT device collect data from various end sensors? The end device connectivity will establish the need for protocol selection.

MQTT would be a good protocol to implement your IoT solution

• If you are connecting M2M devices:

MQTT would be a good protocol to implement your IoT solution

• If you need reliable routing of messages:

AMQP support reliable queuing and flexible routing.