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An Ethernet passive optical network (EPON) is an optical access network that allows a higher data rate with low power consumption. To improve energy savings for an EPON, the sleep and doze modes for the optical network units (ONUs) play a pivotal role. Many prediction schemes have been proposed to control these modes. To increase the prediction accuracy, this study proposes an energy-efficient approach that uses a support vector regression (SVR) model. A dynamic bandwidth allocation (DBA) scheme called SVR-DBA is designed to allocate bandwidth to ONUs more efficiently and fairly. To determine the effectiveness of the proposed scheme, simulations are performed. The simulation results show that the proposed scheme decreases energy consumption for ONUs by up to 47% and fulfills the quality-of-service (QoS) requirements in terms of delay, jitter, and packet loss. [ABSTRACT FROM AUTHOR]

An Ethernet passive optical network (EPON) is an optical access network that allows a higher data rate with low power consumption. To improve energy savings for an EPON, the sleep and doze modes for the optical network units (ONUs) play a pivotal role. Many prediction schemes have been proposed to control these modes. To increase the prediction accuracy, this study proposes an energy-efficient approach that uses a support vector regression (SVR) model. A dynamic bandwidth allocation (DBA) scheme called SVR-DBA is designed to allocate bandwidth to ONUs more efficiently and fairly. To determine the effectiveness of the proposed scheme, simulations are performed. The simulation results show that the proposed scheme decreases energy consumption for ONUs by up to 47% and fulfills the quality-of-service (QoS) requirements in terms of delay, jitter, and packet loss.

The Ethernet passive optical network provides broadband Internet access but also consumes a lot of energy. Energy saving mechanisms using the dual-mode-Active and Sleep modes-design for optical network unit (ONU) in EPON still suffer unnecessary energy consumption, especially in asymmetric data flow such as video streaming downloading service. The Doze mode is particularly suitable for handling the asymmetric data flow since it allows the ONU's transmitter to turn off while turning on its receiver to receive data from optical line termination (OLT). However, adding Doze mode into original dual-mode design incur a greater challenge for OLT to identify the current status of the ONU since the ONU cannot transmit any upstream message to OLT at either Doze or Sleep mode. In this paper, we propose a new QoS provisioning tri-mode energy saving scheme, by integrating the Doze mode into original dual-mode design, to allow the ONU to switch to one of the energy saving modes whenever no upstream traffic exists. A high-priority upstream packet, arriving at ONU of energy saving modes, is able to trigger the ONU back to Active mode for QoS provisioning purpose. Performance evaluation via simulation has demonstrated the effectiveness of such mechanism in various asymmetric data flow. Furthermore, we propose two additional enhanced approaches to increase the energy saving effects by deferring the triggering action of the high-priority upstream packet as well as coalescing new arrival packets during waiting time into the same scheduling cycle. [ABSTRACT FROM AUTHOR]

The majority of the traffic over the Internet is TCP based, which is very sensitive to packet loss and delay. Existing research efforts in TDM-Passive Optical Networks (TDM-PONs) mostly evaluate energy saving and traffic delay performances under different energy saving solutions. However, to the best of our knowledge, how energy saving mechanisms could affect TCP traffic performance in TDM-PONs has hardly been studied. In this paper, by means of our state-of-art OPNET Modular based TDM-PON simulator, we evaluate TCP traffic delay, throughput, and Optical Network Unit (ONU) energy consumption performances in a TDM-PON where energy saving mechanisms are employed in ONUs. Here, we study the performances under commonly used energy saving mechanisms defined in standards for TDM-PONs: cyclic sleep and doze mode. In cyclic sleep mode, we evaluate the performances under two well-known sleep interval length deciding algorithms (i.e. fixed sleep interval (FSI) and exponential sleep interval deciding (ESID)) that an OLT uses to decide sleep interval lengths for an ONU. Findings in this paper put forward the strong relationship among TCP traffic delay, throughput and ONU energy consumption under different sleep interval lengths. Moreover, we reveal that under high TCP traffic, both FSI and ESID will end up showing similar delay, energy and throughput performance. Our findings also show that doze mode can offer better TCP throughput and delay performance at the price of consuming more energy than cyclic sleep mode. In addition, our results provide a glimpse on understanding at what point doze mode becomes futile in improving energy saving of an ONU under TCP traffic. Furthermore, in this paper, we highlight important research issues that should be studied in future research to maximize energy saving in TDM-PONs while meeting traffic Quality of Service requirements. [ABSTRACT FROM AUTHOR]

Current networking equipment usually provides several energy profiles with different performance capabilities. For example, in EPON systems, ONUs are able to switch their transmitters off when there is no data to transmit. This low power mode, known as doze mode, can significantly reduce power consumption in EPONs if wisely used. In this paper, we evaluate through simulation the potential power savings that can be obtained using this mode in many different scenarios. In particular, we analyze the impact of the DBA algorithm and the mode governor on both energy efficiency and frame delay with different implementations of the doze mode. [ABSTRACT FROM PUBLISHER]