On Saturday 09 August 2003 07:29 pm, Tim May wrote:
Cellphones are cheap enough, and monthly charges are small enough when N machines share the same monthly account charge (Dad, Mom, Johnnie, Suzy, and Alarm). I would be surprised if today's alarm companies already aren't making good use of cellphones.
The building where I work has a cellular interface to it's alarm system (Small white box with a 800MHz Antenna sticking out of it next to the central alarm panel). I think the name on the box is something like "CellSentry". It's fed off the batteries for the alarm system so cutting off power won't shut it off either. I have always wondered how the arm/disarm keypad works in most alarm systems. I would hope it would send a reasonably secure code to the controller to disable the alarm system, but I fear that it just a nothing more than a fancy remote relay and can be easily bypassed. They recently added security camers to our system. Instead of using video tape they installed a box that records 30 second snap shots continuoulsy to it's hard drive. Security people can access the system over the network (with a dedicated application, no idea how secure it is) and examine the captured images. -- Neil Johnson http://www.njohnsn.com PGP key available on request.