Experimental evaluation of SCTP tunneling for energy-efficient TCP data transfer over a WLAN

Energy efficiency of wireless clients is an important issue in wireless communications. When multiple network applications are running concurrently on a single wireless client, packets belonging to each application are sent and received independently, but these packets are multiplexed at the MAC level. This uncoordinated behavior makes it difficult to control sleep timing. In addition, transitioning between active and sleep modes frequently will consume a non-negligible amount of energy. To address these difficulties, we have proposed SCTP tunneling: a transport-layer approach that resolves the coordination problem and so reduces the energy consumed by multiple TCP flows on a wireless LAN (WLAN) client. In this study, we perform experiments with off-the-shelf WLAN devices to assess the energy efficiency and the transfer time of SCTP tunneling. We show experimentally that SCTP tunneling with unscheduled automatic power save delivery (U-APSD) can save energy when compared to U-APSD alone, while still increasing file transfer speed.