A tenant in context of the Bosch IoT Hub is a service instance that has been booked by the customer. As multiple customers can subscribe to the Bosch IoT Hub service, each subscription has a unique tenant ID and all tenants are separated from each other.
The multi-tenancy concept of the Bosch IoT Hub is based on handling tenants as own entities. The communication from the devices to the business application and from the business application to the devices is isolated at tenant level.
All service plan limits described in chapter Features and service plans are also tenant-scoped.
More details about multi-tenancy concept can be found the Eclipse Hono Documentation.