Network tech

New network technology wave to slash standby energy use
Imminent new standards promise
to revolutionise the way IT equipment turns itself to standby

While efforts to tackle the IT industry's burgeoning energy consumption have to date largely focused on PCs and the giant server farms that run the internet, the energy used by another critical component of the world's IT infrastructure, the networking technologies that bind everything together, has gone largely unnoticed.
However, from later this year a wave of networking technologies built around new energy-efficient standards are set to emerge, promising to slash IT energy use and save more than $250m (£176m) a year in US energy bills alone.
According to David Law, consultant at network equipment manufacturer 3Com and chairman of one of the Institute of Electrical and Electronics Engineers (IEEE) working groups tasked with developing the new standards, new technologies could soon deliver huge improvements in energy efficiency while slashing the amount of power IT and communications equipment uses when it is on standby.
The new systems are to be underpinned by two new industry standards, IEEE 802.3az for energy-efficient Ethernet and IEEE 802.3at for power over Ethernet, which after years of development should both be formally ratified within the next 18 months.
Law said that the first of these standards, which is due to be voted on this July and should be formally ratified by June 2010, will provide a protocol to replace the current model of ensuring that the Ethernet cable that links a computer to the internet is always on with a more intelligent system.
Under the new standard, that Ethernet link would sit in an idle, power-saving state most of the time and only turn itself on when a "wake signal" lets it know that there is data that needs to be transmitted. Because the laptop or PC would know that data would only be sent following a wake signal, it too would be able to spend more time with certain components in sleep mode, Law explained.
"As the PC or laptop knows it will not have to do anything until it gets the wake signal, it can have adapter cards or port switches in idle too," he added. "One test showed that an adapter card was able to go from consuming one watt to just a tenth of a watt – it might not seem like much, but globally the savings could be massive."
Research from Lawrence Berkeley National Laboratory suggests that using 1G Ethernet cables capable of supporting the new standard would cut US energy bills by up to $250m a year.
The second standard, IEEE 802.3at, similarly promises to revolutionise standby modes for devices with smaller energy requirements, such as phone and wireless internet points.
The standard, which Law said was on track to be ratified this September, will result in an increase in the amount of power that can be transmitted over Ethernet cables from the current level of 12.95W to 25.5W.
Law said that the increase in power would allow a "whole new class of products to be powered over Ethernet cables", such as sophisticated desk phones and wireless access points.
He added that in addition to allowing these new products to do away with mains cables, the technology would allow firms to use the same Ethernet cables to automatically switch the devices to standby when they are not in use overnight or at weekends, potentially delivering sizable energy savings.