Configuration download
Each device can request its initialization configurations at any time via an HTTPs request to Connhex.
Typical scenarios in which this operation is performed by the device are:
- initialization phase: the device has booted for the first time and needs the connection parameters;
- reboot: the device reboots following a reset or power off and requires the updated connection parameters;
- spontaneous check: the device, periodically or following a command, downloads the configurations again to make sure its parameters are up to date.
Authentication mode - config key exchange
The configuration's download request is protected by an authentication key. Three different modes are provided, each with its own key type and procedure, depending on the scenario in which the request is made.
The authentication key is always used in conjunction with an ID that uniquely identifies the device (for example, the serial number or MAC address of the communication module).
The three key types are:
- Initialization key
- Migration key
- Provisioning key
The only key that allows a device to download its configuration is the initialization key.
The other ones can be used, in the specified order, to obtain the initialization key should it not already be stored on the device.
Configuration download flow
Depending on which key the configuration download flow starts with, a different series of steps must be carried out. The following diagram presents the three different options, describing how they are related to each other.