A greener internet

Associate Professor Vijay Sivaraman is developing models for profiling energy consumption of communication networks, and prototyping novel schemes for improving energy efficiency of Internet equipment.

Computers – and the internet in particular – are using way too much power, so Dr Vijay Sivaraman in the School of Electrical Engineering and Telecommunications is working on reducing their power consumption by a factor of 100 in the next 5–10 years.

“Energy consumption of the world is a concern and at the moment the ICT [Information and Communications Technology] sector is about 3% of the total energy consumption, which is about the same  as airlines, but growing rapidly,” Vijay says. “Traffic is doubling every two years on the internet and power consumption is doubling every five years or so. It is believed that ICT will be a main driver  behind the doubling of world energy consumption by 2030. Network equipment accounts for 14% of ICT energy consumption, and the increasing amount of power consumed by internet routers is  becoming a serious concern for router manufacturers and Internet Service Providers (ISPs) alike.”

This has two major implications: firstly, the actual energy consumption of the equipment, and secondly, the heat generated means large computer facilities need vast cool rooms to store computer technology. “Some of this equipment you could cook a pizza on top of it, it’s so hot,” Vijay says. “Cooling costs can be high.”

Vijay’s research has two broad directions: retrofitting existing internet equipment with power-savings modes, such as intelligently putting internal components to sleep; and redesigning internet  architecture to optimise the energy footprint of high-bandwidth (e.g. HD video) services.

“We have made significant progress in the first aspect, demonstrating with real internet traffic traces that over 80% of energy associated with memory in routers can be saved with negligible impact on performance,” he says. “Our method for intelligently putting memory components to sleep is being patented.

“If you want to save power in your house, you switch off lights you are not using,” Vijay says. “In core networks, very often the load is quite low: 10–20%. But there are spikes, so you need to wake up  your system quickly when you need it.”

He says another area of research is based on the principle that equipment is more energy efficient when operated at full load. “If you could somehow force your traffic to go through a smaller set of  routers and just switch the rest of it off, that would make it more energy efficient,” he says.

This research project is part of the GreenTouch consortium, a group of 50 organisations dedicated to creating a sustainable internet, and involves working closely with Alcatel-Lucent, one of the largest manufacturers of telecommunications equipment.