App Turns Bluetooth Phones Into Proximity Locks

Phoenix Technologies has just released a free application for Windows XP and Vista systems that uses the proximity of your Bluetooth-enabled mobile phone to tell your computer when you are away from it and therefore when to lock access to your system. This new app is called Phoenix Freeze, and Phoenix is billing it as security, power-saving, and productivity tool, all rolled into one.

When you install Phoenix Freeze onto your system, the installation wizard automatically looks for Bluetooth mobile phones to pair with, using the app-provided PIN number. You can also pair phones to the app at a later time, after installation. There is nothing to install on the phone itself, other than allowing it to pair via Bluetooth to your PC. Also, if you have multiple systems, you can use the same phone with all of them.

Once Phoenix Freeze is installed and paired with your phone, you adjust the "Distance Threshold" and "Switch Time" for the "Proximity Settings Lock." These settings control how far the phone needs to be from your PC in order for your PC to turn the password lock on, and how soon after this threshold is reached that it will engage. The Switch Time is set in seconds; however the Distance Threshold is not an absolute measurement; you will need to experiment with different Distance Threshold settings in order to find one that matches the desired distance settings for your particular system-and-phone combination. The software is not actually measuring the distance between the system and the phone, but is instead monitoring the diminishing signal strength as the phone moves farther away from the system. The "Proximity Settings Unlock" settings work similarly for determining under what conditions the proximity of your mobile phone will automatically unlock your system.

As to the security angle of Phoenix Freeze, Phoenix sees the application as a seamless means of password-protecting a system. When you step away from your system, it automatically locks the system from prying eyes (unless the owner of those eyes happens to know your password). Bluetooth is still an uncommon accessory for most desktops, however; but it is practically ubiquitous on modern laptops. This means that Phoenix Freeze is much more likely to be used on systems that are portable enough to also be easily stolen--so, while access to the OS might be locked while you are away from your laptop, there is nothing to prevent someone from physically taking your laptop unless you also use some sort of physical anti-theft device, such as a Kensington lock.

As to the application's power-savings potential, you can set Phoenix Freeze to also put your system's display to sleep whenever it locks the system. When you return to your system (with your paired Bluetooth phone), it will automatically unlock and wake up the display. Another option Phoenix Freeze offers is to force the system into sleep mode whenever it locks the system--waking a system from sleep mode, however, requires manually engaging the system's resume button--once the system is asleep it can no longer monitor the Bluetooth connection to automatically detect when the phone is in proximity again.

While this can help reduce overall power consumption of a system, there are a few other variables that might somewhat mitigate the power-savings potential. First of all, not everyone uses Bluetooth peripherals, and therefore many leave Bluetooth turned off on their systems by default. Leaving the Bluetooth antenna always powered on will force those systems to consume more power than they otherwise would--the power consumption from a system's Bluetooth antenna are likely to be minimal, but it can add up over time, and can impact how long a laptop can run on battery before it runs out of juice. The same goes for mobile phones. In order to conserve battery life, many users leave their phone's Bluetooth antenna powered off, unless they use a Bluetooth headset. Leaving Bluetooth on all the time will shorten the amount of time between charges and ultimately means that your phone will need to be charged more frequently.

As to the productivity enhancing capabilities of Phoenix Freeze, the seconds saved from having to manually lock and unlock a system can add up, especially if you are the type who frequently leaves your desk.

Phoenix Freeze is available as a free download from Phoenix, here.