The present document specifies the binding of Mca and Mcc
primitives (message flows) onto the MQTT protocol. It specifies
1) How a CSE or AE connects to MQTT.
2) How an Originator (CSE or AE) formulates a Request as an MQTT
message, and transmits it to its intended Receiver.
3) How a Receiver listens for incoming Requests.
4) How that Receiver can formulate and transmit a Response.