Hi Jecksons,



I was under the impression this was a piece of network equipment mounted in a rack. Now I'm getting the idea that you want to protect something like a laptop computer, or something that is networked wirelessly (which is why you couldn't just look for loss of data on the network). This is certainly a much more interesting problem to say the least.

This is now like a problem I've seen before, securing a firearm such that only the owner could use it. In response to the fact that so many police officers were shot with their own guns (after losing them in a struggle) some gun manufacturers sought to design a system that would prevent a gun from being fired by anyone other than the owner or authorized user. The best solution I saw was a type of rfid technology. The owner was given a ring to wear on his shooting hand that a sensor in the grip could detect. Without the presence of the ring in proximity to the grip, the gun simply would not fire.

Unfortunately, if the cop forgot to put on the ring he was defensless. Similarly, in any scheme you come up with to secure this device, the user is going to have to take responsibility for arming and disarming the system. Even if you give the user some kind of rfid tag for the device to detect (and thereby discern the user from a theif), he or she will have to make sure they have it before they pick up the device.

Now you haven't said (at least not that I've noticed), but I'm going to assume that this device has some sort of user input (keypad, touchscreen, pushbuttons, something). That being the case, and since I'm also now assuming it is wirelessly networked, you could incorporate a gps chip that will report its location anytime someone tries to use it without first entering the correct password, or without the rfid tag nearby, or without first scanning their fingerprint or whatever. If I were doing this I would probably make it report its position periodically (every 10 seconds or 60 seconds or whatever is as frequent as possible without letting the theif notice the use of bandwidth and processor cycles) until the user authenticated that they had possession. What's more, I'd bet that gps chip costs less than the materials you're going to need for that shock sensor. In fact, it's probably no more expensive than a simple mechanical switch.

Even so, I still wouldn't use a shock sensor because of the propensity for false alarms. It just wouldn't be long before the alarms were just ignored.

Good luck,
Joe