A node uses a two dimensional array of transmit queues to store frames to be transmitted from the node to another node. The size of the array is governed by the number of directions to which the other node may forward frames once received from the node, and the number of priorities that may be associated with the frames. The transmit queues are distinguished from each other based on direction and priority. A transmitter transmits frames dequeued from the transmit queues to the other node. Control logic that controls the transmit queues receives an indication from the other node whether the other node is experiencing traffic congestion in any of the directions and the priority of frames at or below which the control logic is to control the dequeuing of frames from transmit queues corresponding to the directions in which the other node is experiencing traffic congestion.