Wasteful Ethernet

06Jul08

Did you know that in 2005 alone, all the network controllers (in computers, switches, routers, etc.) in the United States consumed 5.3 terawatt-hours of energy, sufficient to keep 6 billion 100-watt lightbulbs shining for a full year? As the May issue of IEEE Spectrum reports, a major reason for this is that network controllers maintain the same appetite for energy regardless of whether they are not in use or in full throttle operation. This is incredibly wasteful, since people only use their links at full throttle for 5% of the time on average, studies have shown.

There are currently two competing schemes that aim to address this problem in the near future:

  • Adaptive Link Rate, developed by researchers from USF Tampa and Lawrence Berkeley National Laboratories,  which will step down the speed of an Ethernet link if the full capacity is not needed. The researchers, Ken Christensen and Bruce Norman, claim that simply switching between 100Mb/s and 1Gb/s (in home, office and data-center devices) whenever possible will already save $300m in energy costs. The problem facing their solution is that it currently takes 2 seconds to step down the speed of an Ethernet link (the link has to be dropped and reinstated), which is unacceptable. A faster protocol for linking will be needed, and the pragmatic requirement is set at 1 millisecond.
  • “Low-power idle”, proposed by Intel, in which the controller will always operate at the maximum rate, but will be put into a sleeping state when not in use. Intel claims that this will provide better results. Once again, turning the device on and off is a challenge, but up to 1Gb/s, it is easier than switching speeds. When it comes to 10Gb/s, however, there is no clarity as to which scheme is desirable.

Whereas the call has not been made yet, “a complete redesign of the network interface controller system is needed”, Cisco’s Hugh Barass is quoted as confirming.


Did you know?

In 2010, there will be 4200km of new highways in and around Shanghai, China that didn't exist in 2000. Varese, a town in Northern Italy, runs on 100% renewable power. The town uses a mix of wind, solar and small-scale hydropower. The town has reaped benefits from the energy network through added jobs, and an additional 350,000 euros [US $514,000] in revenues that are handed over to the council each year.

About

SurfaceTension is all about seperating the signal from the noise when it comes to renewable energy, climate change debate, protecting the environment, and embracing green, environmentally friendly technology and energy alternatives.
Environmental Activism Blogs - BlogCatalog Blog Directory

On our way to 1,000,000 rss feeds - millionrss.com