Worked on the rabbitmq/rabbitmq-server repository to enhance MQTT connection management by introducing a configurable disconnection policy for unauthorized topic access. Developed a new mqtt.disconnect_on_unauthorized flag in Erlang, allowing operators to choose between disconnecting clients or maintaining connections with error signaling when unauthorized actions occur. The implementation covered MQTT V5 and V3 protocols, addressing both QoS1 and QoS0 message flows, and ensured consistent disconnect semantics across protocol variants. This backend development effort improved security and operational flexibility, enabling more precise control over client connections and reducing unintended churn, while simplifying policy enforcement for networked systems using MQTT.