Improving Wireless Network Performance under MPTCP based Multipath Access

The emergence of multipath TCP (MPTCP) has made it much easier for mobile devices to use multiple wireless network access paths simultaneously. However, we find that a large amount of multipath users could negatively impact the performance of wireless networks in terms of throughput and fairness due to increased amount of wireless connections. Therefore, in this paper, we aim to mitigate such a problem while retaining the benefits of multipath access in wireless networks from the perspective of network owner. We solve the challenge by 1) identifying a solution principle that can effectively balance the two goals and 2) implementing the principle through an SDN based bandwidth usage management system on the network side. When there is congestion on an AP, our method enforces necessary suppressions on non-primary subflows from multipath users to protect the network performance, while keeping the multipath benefits as much as possible. When an AP owns idled capacity, no intervention is imposed, thus offering the maximal benefits to multipath users without substantially affecting the network performance. Thus, the multipath access is dynamically scaled to achieve a balance of the two goals. Extensive NS3 experiment with Linux Kernel MPTCP implementation demonstrates our findings as well as the effectiveness of the proposed system.