Adaptive Packet Coalescing Mechanism in Energy Efficient Ethernet

摘要

IEEE 802.3az working group has defined Energy Efficient Ethernet (EEE) specification that implements low-power idle (LPI) modes to improve the efficiency of an Ethernet equipment. LPI mechanism allows an Ethernet link to reduce power consumption by entering a low-power sleeping mode and letting some components being powered off when there is no data to be transmitted through the link. However, if small amount of packets are being sent periodically, LPI mechanism cannot obtain energy efficiency due to a high overhead caused by excessive mode transitions. To overcome this problem, packet coalescing mechanism was proposed. Though coalescing improves the energy efficiency, TCP performance might be degraded due to increased packet delay. This paper proposes and evaluates an enhanced packet coalescing mechanism. The simulation results show that proposed mechanism shows higher performance than LPI mechanism with respect to energy consumption rate and packet transmission delay.