Hubs provide features such as message brokering, Device authentication, Networks and Routes.
Devices and services can exchange messages when connected to the same Hub.
You can enable and disable your Hub anytime. When disabled, all Devices will be disconnected and the Hub will not be billed.
There are three IoT Hub plans available:
- Shared: this plan allows you to start using IoT Hub for free, on a shared message broker while still isolated from other users.
- Dedicated: with this plan, your Hub is located on a dedicated message broker with its own resources.
- High-availability (HA): your Hub is backed by a pair of dedicated message brokers, making sure your projects run on a resilient structure.
A table describing the features of each plan in detail is available in the Hub creation wizard on the console.
When you create a Hub, it comes with a Scaleway-generated Certificate Authority. The Hub Certificate Authority is used to authenticate connecting devices through mutual TLS authentication.
The Hub Certificate Authority is used to authenticate Devices. This is not to be confused with MQTT Network certificate authority which allows the Devices to authenticate to the Hub.
If you wish, you can replace the Hub’s certificate authority with your own. Your Device certificates will then have to be signed by this new authority.
Mutual TLS authentication is available only on the Hub’s MQTT Network.
You can refer to the Devices reference documentation to learn more about Device authentication.
Auto-provisioning happens when an unknown Device with a valid certificate (signed by the Hub’s certificate authority) connects to the Hub for the first time. The Device is authenticated and automatically added to the Hub’s Device list.
This feature can be enabled and disabled in the Hub Overview tab of the console.
A Hub event is sent every time a Device is auto-provisioned.
Auto-provisioning only works with mutual TLS, and thus with the Hub’s MQTT Network.
Your IoT Hub generates Events when incidents that require your attention happen. These can be Devices violating the security policies you defined or routes with invalid targets, for example.
When such Events happen, the Hub publishes a message on itself. The topic of the message depends on the event itself, and on a prefix you previously configured. You can receive Events by subscribing to these topics.
Events can be enabled and disabled in the Hub Overview tab of the console. The prefixes can also be configured from the Overview tab.
Event messages will be published using topics under the
prefix/source/identifier/severity format, where:
prefixis the prefix you configured
sourcetells which resource type triggered the event (hub, device, route, …)
identifieris the resource identifier (hub ID, device ID, route ID, …)
severitytells how important the event is (info, warning, error, …)
For more information about events, check out how to understand event messages.
Hubs generate 2 usage metrics:
- Message count: tells you how many messages are transited through your Hub. Any MQTT message, whether it is a data or a control message, is counted as a Hub message.
- Active devices: tells you how many different Devices have been connected to your Hub.
All metrics are provided within 5 available ranges:
- last 60 minutes: 1 per minute
- last 24 hours: 1 per hour
- last 7 days: 1 per 4 hours
- last 30 days: 1 per day
- last 365 days: 1 per month
The Hub metrics are available in the Hub Metrics tab of the console.
|MQTT messages payload||4MiB|
|Hub reserved memory (1)||140MiB|
|Maximum number of Hubs - Shared plan||5|
|Maximum number of Hubs - Dedicated plan||50|
|Maximum number of Hubs - HA plan||50|
(1) Hub reserved memory is the total memory reserved per Hub to store the retained, inflight and will messages.