Analytical TCP characteristics under power-saving control in passive optical networks

This article provides an analytical consideration of transmission control protocol (TCP) characteristics when under the sleep control of passive optical networks (PON) systems. We show that the TCP’s initial throughput growth is delayed by sleep control with a large round trip time (RTT), where the guard time used to make the sleep decision expires before the next packet train arrives. We modeled the adverse impact caused by sleep control in terms of congestion window growth. We confirmed that our model successfully approximated the experimental result obtained in an actual environment. We also provide a guideline for solving this problem that takes account of power-saving efficiency.