Abstract. Numerous studies have shown that packet reordering is common, especially in high speed networks where there is high degree of parallelism and different link speeds. Reordering of packets decreases the TCP performance of a network, mainly because it leads to overestimation of the congestion of the network. We consider wired networks and analyze the performance of such networks when reordering of packets occurs. We propose an effective solution that could significantly improve the performance of the network when reordering of packets occurs. We report results of our simulation experiments, which support this claim. Our solution is based on enabling the senders to distinguished between dropped packets and reordered packets.