The embodiments are directed to methods and appliances for scheduling a packet transmission. The methods and appliances can assign received data packets or a representation of data packets to one or more connection nodes of a classification tree having a link node and first and second intermediary nodes associated with the link node via one or more semi-sorted queues, wherein the one or more connection nodes correspond with the first intermediary node. The methods and appliances can process the one or more connection nodes using a credit-based round robin queue. The methods and appliances can authorize the sending of the received data packets based on the processing.