ECS4110-28T_Management Guide

C HAPTER 27 | Interface Commands
Power Savings
– 1020 –
checks for energy on the circuit to determine if there is a link
partner. If none is detected, the switch automatically turns off the
transmitter, and most of the receive circuitry (entering Sleep Mode).
In this mode, the low-power energy-detection circuit continuously
checks for energy on the cable. If none is detected, the MAC
interface is also powered down to save additional energy. If energy
is detected, the switch immediately turns on both the transmitter
and receiver functions, and powers up the MAC interface.
■
Power saving when there is a link partner:
Traditional Ethernet connections typically operate with enough
power to support at least 100 meters of cable even though average
network cable length is shorter. When cable length is shorter, power
consumption can be reduced since signal attenuation is proportional
to cable length. When power-savings mode is enabled, the switch
analyzes cable length to determine whether or not it can reduce the
signal amplitude used on a particular link.
N OTE : Power savings can only be implemented on Gigabit Ethernet ports
using twisted-pair cabling. Power-savings mode on a active link only works
when connection speed is 1 Gbps, and line length is less than 60 meters.
EXAMPLE
Console(config)#interface ethernet 1/1
Console(config-if)#power-save
Console(config-if)#
show power-save This command shows the configuration settings for power savings.
SYNTAX
show power-save [interface interface]
interface
ethernet unit/port
unit - Unit identifier. (Range: 1)
port - Port number. (Range: 1-24/48)
COMMAND MODE
Privileged Exec
EXAMPLE
Console#show power-save interface ethernet 1/1
Power Saving Status:
Ethernet 1/1 : Enabled
Console#