Green at home

The computer magazines are full of “green’ and IBM is running adverts about green that are painting the server room walls green. Green is obviously one of the hot IT buzzwords.

But what about home computing?

With the advent of DSL and cable internet many homes are running “always on” internet. This is a big “multiplier”.

Those of us who are smart have a firewall at the CPE doing the ‘always on’ part. I also have a server that uses fetchmail to fetch the mail from all the mailboxes I have around the world, so limiting my exposure.

While there are very low energy consumption machines like the Asus or solar powered laptops or very low power hacks this is all leading edge stuff. Many homes are running “legacy” equipment.

My firewall, for example, is an old HP Vectra desktop. It also makes a nice support for my monitor. The monitor is ‘Energy Star’ compliant and powers itself down. My server and laptop are more modern and have energy saving features. Since I run Linux I make use of ‘powersave‘ to use the BIOS to throttle the CPU and shut-down disk activity.
Similar features exist for Windows.

The issue is “how many people use them?”

It would be nice for the green advocates if machines shipped with powersave features turned on, but its also easy to imagine grandma at her PC pecking out the letters while sending e-mail pausing to think what to say next and seeing her screen go blank. Panic sets in.

Ah, awareness. Always an issue.

So what does this have to do with security?
Well, apart from grandma panicking, this is one more thing that can affect issues such as availability. While a battery-conserving road-warrior will tolerate the delay of disk start-up, its not appropriate in many other settings. Certainly not in a server farm!

Often the IT world can become obsessed with issues that are tangential to its main focus. Being Green should be a corporate strategy, one that is systemic. There are many other ways that a corporation can cause energy to be consumed other than its own electrical demands.

Telecommuting might seem a good idea but do work out the details. Is it more energy efficient for workers to come to an office and turn their own home energy demands down? Crunch the numbers. It may be less expensive for the company, allow it to have smaller premises and energy demands, but all its doing if offloading its energy demands onto its telecommuters. Good for its own profits but short-sighted with respect to the community at large.

And “going green” by telecommuting has its own InfoSec risks!

About the author

Security Evangelist


  1. When your CPU isn’t executing intructions, it enters an idle mode and consumes far less energy. Any program that keeps the CPU from entering this idle state will cause your machine to consume more power, regardless of how processor intensive the process is.

    The Linux 2.6.21 kernel introduces the so called tickless-idle feature. This feature allows the processor to be really idle for long periods of time, rather than having to wake up every millisecond for the timer tick.

    So, if you want to tune your Linux box for ultimate power efficiency, enable the tickless-idle feature in your kernel. It will help, but you also need to find out what programs are causing the machine to wake-up.

  2. For Linux user, the powertop utility can be used to see what is bringing your machine out of idle and causing it to consume power.

    On my machine Mozilla Thunderbird an Mozilla Firefox are the big culprits

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