TCP congestion control with ACK-pacing for vertical handover

In this paper, we discuss TCP congestion control in the future heterogeneous mobile Internet where various access links such as a wireless LAN and a cellular network are integrated. Vertical handover (VH), which is a handover technique between different types of access links, is one of the most important technologies. However, the vertical handover significantly degrades the performance of TCP because it causes a drastic change of the bandwidth-delay product (BDP). In this paper, we propose a new congestion control for improving TCP performance during vertical handover. The proposed system is receiver driven and the TCP receiver controls the sending rate by ACK pacing. With computer simulation, we have shown that the proposed system adjust its congestion window size to a target BDP value rapidly and can achieve a good throughput performance.