All in the <head> – Ponderings and code by Drew McLellan –

Bluetooth KVM

A KVM switch, as you may know, is a device that enables you use a single keyboard, VDU and mouse (hence KVM) to operate multiple machines. It uses either a physical switch or more commonly a special key combination and an OSD to switch between connected machines. KVM switches are found mostly in server rooms, but also sometimes on the desks of geeks who need physical access to more than one computer.

The need for such a switch stems from the physical limitation of needing to connect devices together with wires. Get rid of the wires and you can do the switching with software instead of hardware. With the increasing availability of bluetooth keyboards and mice, a simple bluetooth KxM switch surely must follow. I don’t know for sure, but I’m guessing that the data rate available with bluetooth is far lower than that required my a VDU. However, as many VDUs have more than a single input, such a device could prove useful to your average multi-computer geek.

Any host-based software KxM switching is going to have to be pretty intelligent. You’d essentially need a client running on each computer interfacing the input devices with the operating system. On receiving the magic key combination, the software would need to nullify all input from the keyboard and mouse for its local host, and broadcast a message over the network to the next client in the list so that it can assume control.

Of course, if you had an intelligent keyboard the whole thing could be done far more simply. You’d need to pair the keyboard with the mouse so that the switch needed to be made on only one device – the keyboard could issue control commands to the mouse. You’d need to then pair the keyboard with each computer in turn. Hit the magic key combination and the keyboard could then pick the host to whom it would transmit.

Combine this with a smart VDU which takes multiple inputs and accepts selection commands via bluetooth, and Bob, as they say, is your uncle.