Green Ethernet

D-Link, one of the largest small router and switch manufacturers, has Green Ethernet switches on shelf recently. Viewing global warming, it becomes essential for human being to save energy consumption. Various efforts have been taken for this purpose. Green Ethernet is one of these good examples. Viewing hundreds of millions of Ethernet interfaces, such an effort is expected to significantly contribute to human being’s efforts on Earth greening.

The major ideas of energy saving in D-Link products include:

• By keeping on monitoring the activity of an Ethernet interface, the switch can configure the interface to be in “sleeping mode” if there is not data transmission.
• The Green Ethernet can detect the cable length and transmit data with a power that is sufficient for the data to reach other end. For example, if the cable length is 20 m, the switch interface can use a low power for transmission; however, if the cable length is 100 m, then more power should be turned up for longer distance transmission.

Benefits

• If computers connected to the switch are turned off, D-Link’s Green Ethernet can save up to 85.65% power.
• If cable length is less than 20 m, D-Link’s Green Ethernet can save up to 9.3% power used.

Sample power saving table (from D-Link http://www.dlink.com/corporate/environment/dlink-green-ethernet/)-