In a distributed router containing routing nodes connected by a switch fabric, an input-output processor for use in the routing nodes. The input-out processor comprises: 1) an input interface controller for receiving incoming data packets from N input links; 2) an output interface controller for transmitting outgoing data packets to the switch fabric via a first uplink and a second uplink. Each of the N input links is assigned to one of the first and second uplinks so that incoming data packets from each input link are transmitted to the switch fabric by the assigned one of the first and second uplinks. The input-out processor also comprises 3) a load balancing controller for i) determining first and second uplink traffic levels on the first and second uplinks, ii) determining a difference between the first and second uplink traffic levels, iii) comparing the difference to a predetermined threshold, and, iv) in response to a determination that the difference exceeds the predetermined threshold, reassigning at least one input link from the uplink having the greater uplink traffic level to the uplink having the lesser uplink traffic level.