Proactive Multipath TCP for Seamless Handoff in Heterogeneous Wireless Access Networks

Multipath TCP (MPTCP) is a new evolution of TCP that enables a single MPTCP connection to use multiple TCP subflows transparently to applications. Each subflow runs independently allowing the connection to be maintained if endpoints change; essential in a dynamic network. Differentiating between congestion delay and delay due to handoffs is an important distinction overlooked by transport layer protocols. Protocol modifications are needed to alleviate handoff induced issues in a growing mobile culture. In this paper, findings are presented on transport layer handoff issues in currently deployed networks. MPTCP as a potential solution to addressing handoff- and mobility-related service continuity issues is discussed. Finally, a handoff-aware cross-layer-assisted MPTCP (CLA-MPTCP) congestion control algorithm is designed and evaluated.