A low-complexity delay injection algorithm for improving TCP performance during LTE intra handover

While the wireless technologies have experienced remarkable improvement for decades, TCP protocol haven´t been properly supported the mobility features of advanced wireless networks like 3GPP Long Term Evolution(LTE). Especially for handover, TCP performance is seriously degraded by spurious timeout since the core network is congested by data forwarding between serving eNodeB and target eNodeB. In this paper, we propose a low-complexity delay injection algorithm for reducing packet forwarding during LTE intra handover. In the proposed algorithm, artificially manipulated delay is injected, when TCP acknowledge is sent, to increase the interval of new packet arrival from the server. By doing so, packet forwarding between serving eNodeB and target eNodeB can be reduced. The proposed algorithm makes no alteration in TCP function and the standard LTE intra handover procedure. And every procedure of the proposed algorithm operates at ME simplicity of implementation. Simulation results show that the proposed algorithm successfully reduces timeout during handover. And also total TCP throughput of the entire core network increases since the proposed algorithm effectively reduces redundant use of resource in the core network.