Reducing Power To Idle Queue Circuits; Command Usage - AMX NXA-ENET8-2POE Operation/Reference Manual

Reducing Power to Idle Queue Circuits

Use the EEE Configuration page to configure Energy Efficient Ethernet (EEE) for specified queues, and to
specify urgent queues which are to transmit data after maximum latency expires regardless of queue length.
FIG. 34 EEE Configuration
EEE Configuration parameters
• Port
• EEE Enabled
• EEE Urgent
Queues

Command Usage



1.
Click Configuration, Power Reduction, EEE.
2.
Select the circuits which will use EEE.
3.
If required, also specify urgent queues which will be powered up once data is queued and the default
wakeup time has passed.
4.
Click Save.
NXA-ENET8-2POE Gigabit Ethernet Layer 2 PoE Switch
Port identifier.
Enables or disables EEE for the specified port.
Specifies which are to transmit data after the maximum latency expires regardless
queue length.
EEE works by powering down circuits when there is no traffic. When a port gets data to be
transmitted all relevant circuits are powered up.
The time it takes to power up the circuits is call the wakeup time. The default wakeup time is 17 µs
for 1 Gbps links and 30 µs for other link speeds. E
EE devices must agree upon the value of the wakeup time in order to make sure that both the
receiving and transmitting devices have all circuits powered up when traffic is transmitted. The
devices can exchange information about the device wakeup time using LLDP protocol.
To maximize power savings, the circuit is not started as soon as data is ready to be transmitted from
a port, but instead waits until 3000 bytes of data is queued at the port. To avoid introducing a large
delay when the queued data is less then 3000 bytes, data is always transmitted after 48 µs, giving a
maximum latency of 48 µs plus the wakeup time.
If required, it is possible to minimize the latency for specific frames by mapping the frames to a
specific queue (EEE Urgent Queues). When an urgent queue gets data to be transmitted, the circuits
will be powered up at once and the latency will be reduced to the wakeup time.
Configuring the NXA-ENET8-2POE
45