ProSCH: Proxy aided Secondary Cell Handover in Ultra-Dense mmWave Network

Abstract

The ultra-dense network (UDN) is a promising technology that overcomes the instability of high-frequency millimeter wave (mmWave) communication in a cellular network. With a short distance between cells and variability of mmWave, a handover occurs frequently in UDN with mmWave. Hence fast handover is essential to provide reliable service. One of the important things for fast handover is prompt signaling between base stations (BSs) through backhaul. However, conventional handovers assumed backhaul has very short latency with ideal deployment. In practice, with non-ideal latency and deployment of backhaul, handover is delayed for backhaul. We find that this delayed handover led to the performance reduction of TCP, the dominant traffic of nowadays. So we propose a ProSCH, the novel handover scheme that operates on a practical backhaul network while guaranteeing TCP performance. ProSCH reduces a handover interruption time by considering the backhaul latency in the handover signaling process and uses a TCP proxy on BS to forward data without loss after handover. Through extensive ns-3 simulation, we show that ProSCH outperforms conventional schemes in terms of handover interruption time, backhaul load, throughput, and delay.