Experimental Performance Study of Multipath TCP over Heterogeneous Wireless Networks

Multipath TCP (MPTCP) enables a single TCP connection to use multiple paths for data delivery. This is expected to increase the overall data transfer throughput by utilizing the multihoming capabilities of communicating nodes. This paper introduces an experimental study of MPTCP connections of multihomed wireless nodes. The nodes' transceivers use two wireless interfaces. One is connected to a WiFi network, whereas the other emulates a dedicated link (such as a 3G or 4G). The performance of MPTCP is investigated in a practical setting, where the WiFi network suffers from interference of other nearby WiFi networks. The effect of connection parameters (such as maximum segment size and receiver buffer size) is examined. For such multihomed connections, our findings demonstrate that the MPTCP coupled congestion control algorithm can transfer more traffic over the WiFi link than the dedicated link only if the WiFi channel rate far exceeds the dedicated link rate.