A system for optimizing network traffic is described. The system includes a quality of service (QoS) engine configured to acquire information regarding a plurality of data packets comprising a plurality of data packet flows operating over a plurality of links. The QoS engine can be further configured to determine a flow priority to the plurality of data packets flows, and to determine TCP characteristics for the plurality of data packet flows. The system further includes a TCP controller configured to acquire the flow priority to the plurality of data packets from the QoS engine. The TCP controller can be configured to obtain queue information associated with the plurality of data packets, and adjust a receive window size based on the flow priority and the queue information.