Until he chimes in, I’ll give it a go.
IGLA is a tiny device that is installed in a hidden location somewhere in your CAN wiring (could be virtually anywhere in the truck). It’s untraceable and can only be found by unwinding the tape and seeing it. It’s called IGLA because that’s the Russian word for needle (it’s thin like a needle).
IGLA is an immobilizer that stops attempts to program a new key, put the vehicle in gear, etc. It effectively prevents all means of electronic theft. Obviously, it doesn’t prevent a flat-bed tow.
You disarm IGLA by either entering a custom PIN code on the steering wheel, or carry a tiny fob in your pocket. I carry the fob, so it requires virtually zero effort on my part to have it.
Since IGLA is silent and hidden, it doesn’t provide any deterrent. So thieves will still break in and spend time tearing the dash apart in an attempt to steal the truck. That’s why most people pair it with Compustar (which is a more traditional alarm with a shock sensor). This pairing provides the best protection.