Lab : Energy Efficient Ethernet (EEE)

Objective : The goal of the lab is to check the effectiveness of Energy Efficient Ethernet (EEE) using cisco switch, how much energy is saved when EEE is activated and the difference in energy consumption when EEE is disabled.

Equipement : 2 Cisco WS-C2960X, 2 PCs, Watt meter.

Energy Efficient Ethernet (EEE) is an IEEE 802.3az standard that is designed to reduce power consumption in Ethernet networks during idle periods. EEE protocol uses a low power idle (LPI) signal that is modifications of the normal idle transmitted between data packets. The transmitter sends LPI in place of idle to indicate that the link can go to sleep. After sending LPI for a period (Ts = time to sleep), the transmitter can stop signaling altogether so that the link becomes quiescent (inactive). Periodically, the transmitter sends some signals so that the link does not remain quiescent for too long without a refresh. Finally, when the transmitter wishes to resume the fully functional link, it sends normal idle signals. After a predetermined time (Tw = time to wake), the link is active and data can be sent.