Supporting multiple users and operators in a single IoT system is vital for large-scale commercial deployments. This involves servicing numerous network operators with one IT system and set of devices, ensuring each operator can manage, reconfigure, and change device settings securely. This paper evaluates a multi-tenancy solution in our test system (TS), utilizing Apache Kafka as a message broker and OpenLDAP as an authorizer. It describes the system design, methods to ensure data separation, security and results of performance evaluation in simulation.