Configuring Green Ethernet - Cisco SF500-24 Administration Manual

Port Management

Configuring Green Ethernet

Configuring Green Ethernet
Cisco 500 Series Stackable Managed Switch Administration Guide
This section describes the Green Ethernet feature that is designed to save power
on the switch.
It contains the following sections:
• Green Ethernet Overview
• Setting Global Green Ethernet Properties
• Setting Green Ethernet Properties for Ports
Green Ethernet Overview
Green Ethernet is a common name for a set of features that is designed to be
environmentally friendly, and to reduce the power consumption of a device. Green
Ethernet is different from EEE in that green ethernet energy-detect is enabled on
all devices where only the Gigabyte ports are enable with EEE.
The Green Ethernet feature can reduce overall power usage in the following ways:
• Energy-Detect Mode—On an inactive link, the port moves into inactive
mode, saving power while keeping the Administrative status of the port Up.
Recovery from this mode to full operational mode is fast, transparent, and no
frames are lost. This mode is supported on both GE and FE ports.
• Short-Reach Mode—This feature provides for power savings on a short
length of cable. After cable length is analyzed, the power usage is adjusted
for various cable lengths. If the cable is shorter than 50 meters, the switch
uses less power to send frames over the cable, thus saving energy. This
mode is only supported on RJ45 GE ports; it does not apply to Combo
ports.
This mode is globally disabled by default. It cannot be enabled if EEE mode
is enabled (see below).
In addition to the above Green Ethernet features, the 802.3az Energy Efficient
Ethernet (EEE) is found on devices supporting GE ports. EEE reduces power
consumption when there is no traffic on the port. See the
Efficient Ethernet Feature
only).
EEE is enabled globally by default. On a given port, if EEE is enabled, short reach
mode will be disabled. If Short Reach Mode is enabled, EEE will be grayed out.
section for more information (available on GE models
10
802.3az Energy
142