Green Ethernet - Vivotek AW-GEV-264A Series User Manual

3-2 Green Ethernet

EEE is a power saving option that reduces the power usage when there is low or no traffic
utilization.
EEE works by powering down circuits when there is no traffic. When a port gets data to be
transmitted all circuits are powered up. The time it takes to power up the circuits is named
wakeup time. The default wakeup time is 17 us for 1Gbit links and 30 us for other link speeds.
EEE devices must agree upon the value of the wakeup time in order to make sure that both the
receiving and transmitting device has all circuits powered up when traffic is transmitted. The
devices can exchange wakeup time information using the LLDP protocol.
EEE works for ports in auto-negotiation mode, where the port is negotiated to either 1G or 100
Mbit full duplex mode.
For ports that are not EEE-capable the corresponding EEE checkboxes are grayed out and
thus impossible to enable EEE for.
When a port is powered down for saving power, outgoing traffic is stored in a buffer until the
port is powered up again. Because there are some overhead in turning the port down and up,
more power can be saved if the traffic can be buffered up until a large burst of traffic can be
transmitted. Buffering traffic will give some latency in the traffic.
Web Interface
To configure a Port Power Saving Configuration in the web interface:
1. Click Configuration, Green Ethernet
2. Evoke to enable or disable the ActiPHY, PerfectReach, EEE and EEE Urgent Queues .
3. Click Apply.
Figure 3-2.1: The Port Power Saving Configuration
User Manual rev. 1.2. Aug. 2015
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