Cross-layer path management in multi-path transport protocol for mobile devices

MPTCP is a new transport protocol that enables mobile devices to use several physical paths simultaneously through multiple network interfaces, such as WiFi and cellular. However, wireless path characteristics change frequently in mobile environments, causing challenges for MPTCP: For example, WiFi associated paths often become unavailable as devices move, since WiFi has intermittent connectivity caused by the short signal range and susceptibility to interference. In this work, we improve MPTCP to manage path usage based on the associated link status. This variant, called MPTCP-MA, uses MAC-Layer information to locally estimate path quality and connectivity. By suspending/releasing paths based on their quality, MPTCP-MA can more effectively utilize restored paths. We have implemented and deployed MPTCP-MA in Linux and Android. Our experimental results show that MPTCP-MA can efficiently utilize an intermittently available path, with Wifi throughput improvements of up to 72 percent. © 2014 IEEE.