# Message Protocols

## Where to begin

* __Communication Sniffing__ on unsecured connections
* __Source code analysis__
* __Documentation__

## Message Queueing Telemetry Transport (MQTT)

Queues on a Broker are used through a __publish/subscribe__ model as an asynchronous connection in the following way

* Publisher sends data to a queue of the broker
* Broker holds the message in Topics (queues) for period of time
* Subscriber may connect and get the message from the Broker via Topics

### Tools

* `nmap` to list the topics
* `mosquitto_sub -h <hostname> -t <topic>` to subscribe to topics or query the device ID
* `mosquitto_pub -h ` to publish to topics through mentioning the device ID