On the Impact of Packet Reordering in MPT-GRE Multipath Networks

Several factors, such as network delays, congestion, differing path lengths, and varied processing durations at intermediary nodes, can cause out-of-order arrival of the packets, negatively affecting network performance, decreasing throughput, and increasing latency. When packets arrive out of order, the receiver may need to wait for missing packets before assembling a complete message, resulting in additional delays. Furthermore, some applications, like music and video streaming, require continuous and ordered data flow. Any out-of-order arrival of packets can result in jitter and decreased quality. To mitigate the impact of this issue in MPT-GRE multipath networks, MPT contains a packet reordering mechanism. In this paper, we designed a network topology that generated delays and limited the transmission speed on one of the paths. We investigated how the out-of-order arrival of packets influences the throughput aggregation capability of the MPT library with and without enabling the packet reordering feature of MPT. Our network throughput measurements show that by enabling MPT's packet reordering mechanism, MPT can efficiently aggregate the throughput of both symmetric and asymmetric channels.