A network device receives, from a congestion controller, traffic policy information associated with a data stream between a sender and a receiver, where the traffic policy information includes a maximum round trip delay time (RTT) and a maximum throughput rate (Rate). The network device obtains a receiver advertised window size (RWND) for the receiver for the data stream. The network device modifies the RWND based on the RTT and the Rate to produce a modified receiver window size (RWND′) and sends the RWND′ to the sender for use in controlling congestion on the data stream between the sender and the receiver.