One of the challenges of Green IT is making sure that desktop PCs in offices are not using power when they’re not needed. That means using power management software to put machines into sleep mode (better still, turning them off at night). But it’s not always straightforward in offices where access from remote locations may be needed.
Microsoft Research has come up with a solution that allows desktops to be put into sleep mode whilst ensuring that remote users can connect to the sleeping machines and IT administrators and automated scripts can execute maintenance tasks. It has already deployed the solution for six months internally, with 50 active users
Full details are here, but the basic idea is that a proxy representing the desktop allows the machine to pretend to be available on the network even when sleeping. All traffic meant for the sleeping client is sent to the proxy. The desktop is woken up automatically when needed by a user or an automated script, i.e. it only wakes for certain specified traffic.
Microsoft says that the approach made significant energy savings, with most machines sleeping over 50% of the time while maintaining their network accessibility.
The downside was that Microsoft found that much potential sleep was lost due to interference from IT management tasks. The company sees fixing this issue as the main path to improving energy savings and some suggestions are made in the paper. It’s also going to get more complicated if cloud-based applications become more widely adopted - more specialised proxy reaction policies will be needed.
Microsoft is not the only one looking into this area, but believes it’s the first one to put a solution to the test. It’s a worthwhile process. The company says that a typical desktop with a 17 inch LCD consumes over 100W when powered on, while a sleeping computer consumes only 2-3W. But as with all things technology, solving one part of the problem raises other issues. The next improvement may be more down to better processes and procedures for remote desktop maintenance.