An active queue management (AQM) process for network communications equipment. The AQM process is queue based and involves applying at a queue size threshold congestion notification to communications packets in a queue of a link via packet dropping; and adjusting said queue size threshold on the basis of the congestion level. The AQM process releases more buffer capacity to accommodate more incoming packets by increasing said queue size threshold when congestion increases; and decreases buffer capacity by reducing said queue size threshold when congestion decreases. Network communications equipment includes a switch component for switching communications packets between input ports and output ports, packet queues for at least the output ports, and an active queue manager for applying congestion notification to communications packets in the queues for the output ports via packet dropping. The congestion notification is applied at respective queue size thresholds for the queues, and the thresholds adjusted on the basis of the respective congestion levels of the queues of the output ports.