Registration and Connection Flow


The Registration phase allows a device to connect to the server with unique and secure keys so that no one can pass themselves off as that device. For the creation of keys and certificates, unique features of the gateway are used that cannot be reproduced by others.
The Registration phase of a Device involves the generation of a 2048bit RSA key by the EDGEHOG Device Manager Agent, from which a CSR (Certificate Signing Request) is derived. The CSR is sent to the EDGEHOG Portal, which returns the certificate to the EDGEHOG Device Manager Agent on the Device which will allow it to establish the MQTT connection to the broker.
The registration process is started automatically when a clean version of EDGEHOG OS is loaded on the gateway. If this procedure is not successful, it will be repeated at incremental intervals of 5 minutes (to limit network traffic, there will be a 5-minute interval between the first and second request, between the third and fourth 10 minutes, between the fourth and fifth 15 minutes and so on) for a maximum of 60 minutes between subsequent requests.
When the EDGEHOG Device Manager Agent on the Device establishes the MQTT connection, a LED will light up, if foreseen by the hardware, according to the criteria indicated in the Connection Flow section.

Connection Flow

Where provided by the hardware, a Blue LED is used to indicate the connection states to the EDGEHOG Server Portal.
In the table below you can see what is indicated by the Blue LED states:
Behavior description
The LED is off until the registration phase starts
LED slow blink
The LED blink slowly during the bootstrap and register phases (1s ON - 1s OFF)
LED fast blink
The LED blink quickly during MQTT connection (200ms ON - 200ms OFF)
LED ON stable
The LED is stably on if the MQTT connection is stable (it can subscribe to topics and publish on the shadow). The LED blinks every 10s for 500ms to show that the connection is active and not stalled.