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Displays Power Hardware

Sonar Software Detects Laptop User Presence 167

Steve Tarzia writes "A research group at Northwestern University and University of Michigan has released open-source display power-management software that uses a new user presence detection technique. The goal is to shut off the display immediately when the user leaves the computer rather than using slow and error-prone mouse/keyboard activity timeouts. Surprisingly, the mic and speakers of many laptop computers are sensitive to ultrasonic frequencies. Those frequencies can be used to silently probe the laptop's physical environment. This software is based on research published at the UbiComp2009 conference. A Windows binary and source code for Windows and Linux are available for download."
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Sonar Software Detects Laptop User Presence

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  • Re:Activity (Score:5, Insightful)

    by lordandmaker ( 960504 ) on Thursday October 15, 2009 @05:34PM (#29762911) Homepage

    Mouse/keyboard activity timeout works nicely for that.

    I find it doesn't. My PC at work has to be configured to require a password be entered on exiting the screensaver, and my password has to be quite complex. If I'm working on something that's not the PC (yeah, we still use paper for things) for longer than the minute, I've got to enter my password to carry on, which is irritating.
    It's less irritating when it kicks in when I'm reading or watching a video or something, but I'd still prefer it not to, and I really don't see the privacy angle on this. It's no idea where I am, just that there's something in front of it.

    But, generally, I don't have much of a problem with my computer knowing all sorts of stuff about me, it's what it tells to who that I concern myself with.

  • Headphones (Score:4, Insightful)

    by quantumphaze ( 1245466 ) on Thursday October 15, 2009 @05:36PM (#29762939)

    This wouldn't work with headphones plugged into the computer unless you can get the laptop's built in speakers working independantly (it can do it, old Ubuntu 7.10 had them on separate mixer controls on my laptop). But desktop users usually have their powered speakers off when using headphones.

    Does anyone have an idea on how to solve that? You could put out ultrasonic sound through the headphones that get blocked when used, but it could damage your hearing depending on how loud it needs to be to get picked up by the microphone.

  • Re:Activity (Score:3, Insightful)

    by BitZtream ( 692029 ) on Thursday October 15, 2009 @05:58PM (#29763217)

    Your instant messenger will know when your available or not.
    Your phone system could direct your calls to you mobile if your away from the desk.

    I think this is EXACTLY what he is concerned with. Do you realize how much information you tell others in the world about you with JUST your IM status? Do you realize how easy it is to use this simple bit of information already to plot crimes? Give me a week of watching little more than the IM status of active IMs and twitterers and I can pretty much tell you where you are at during any point in your day if your using a regular schedule.

    He cares and is concerned about this potential problem.

    You haven't even realized how big of a problem it is.

    Roughly speaking, IM status is nearly as good as hang a sign on your home that automatically says 'No One Home!' when you leave.

  • by rtfa-troll ( 1340807 ) on Thursday October 15, 2009 @05:59PM (#29763231)
    It would be nice if they would make the software license clear. Even if just to say that "this is government sponsored and so available for copying with no restrictions". Also at the bottom of the page they say '"Windows" is a registered trademark of the Microsoft Corporation.' but forget to mention that Linux is a registered trademark of Linus Torvalds.
  • Re:Activity (Score:4, Insightful)

    by maharb ( 1534501 ) on Thursday October 15, 2009 @06:22PM (#29763461)

    IM status can be set manually so if you are concerned about privacy... set it manually. Not to mention just because your SYSTEM knows things about you doesn't mean you must pass it on to any app, especially networked ones. Your system knows all sorts of things that it doesn't readily share.

    Believe it or not people can determine all sorts of things about you IRL just by watching too. In fact, IRL, you are way more prone to being tracked and monitored than online. Imagine, someone can see you leave your house, go in, steal shit, and leave all by watching you. We need to fix that bug IRL asap.

    I can't believe the level of unjust paranoia you are experiencing. The fact is if people care enough to track you, they will be able to. It doesn't matter if you have a laptop that turns off when you leave it or not. Also, how does a 5 minute delay from a regular inactivity time out differ from this so much that this tech is all of the sudden dangerous. It seems to me like people can be monitored via IM just as easy right now as if this was being widely used, just with a tad bit more 'false present' status existing.

  • Re:Activity (Score:3, Insightful)

    by socceroos ( 1374367 ) on Thursday October 15, 2009 @06:39PM (#29763637)
    I would suggest that if you were in a high-sensitivity location you shouldn't have this software at all. Because, all it would take is for someone to keep your desktop from locking when you walk away by spoofing your bluetooth connection.
  • Re:I wonder how... (Score:5, Insightful)

    by tkw954 ( 709413 ) on Thursday October 15, 2009 @07:38PM (#29764215)

    Asus ships the software you're describing with laptops they sell; it came on mine. It takes a bunch of snapshots of your face through the webcam (you're supposed to rotate your head) and then if it sees your face at the login screen, it logs you in.

    So all I need to log on to your computer is a lifesize photo of you, or alternately, your severed head?

  • Re:Activity (Score:3, Insightful)

    by RMH101 ( 636144 ) on Friday October 16, 2009 @04:51AM (#29766619)
    How would you suggest turning off a laptop mic? No hardware switch to do so (unless you've a BIOS option to do it, which I doubt). You could disable the sound card in device manager, but then you've no audio. Seems a valid security issue - nothing stopping an app turning it up in the mixer and recording...

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