Drones querying ID, How exactly does this work? Options

[Moon-Hawk]

Okay, here's the situation I'm envisioning:

Someone is walking around in a big corporate enclave thing. Indoors, outdoors, it's not the point. The point is it's an area with authorized personnel only, either all the time or maybe just as an after-hours thing. A drone rolls up and queries their commlink or somehow verifies their identity. If they are "on the list" it moves on. If they're not it notifies security personnel who come to have a chat. If the person runs, or maybe if security already has an active alert going it opens fire with gel rounds and then waits for security personnel to show up.

My question is, how does this work, game mechanically, and how would it be beaten? Is it simply a user account linked to that commlink on their security network? If you hack the security network with security or better access can you add a user account and be in the clear? If a drone is interrogating you, can you spoof a command to just that one to get off the hook, but still have to worry about others? If it is just a commlink account, I suppose you'd need something to keep you from simply whacking the janitor and stuffing his 'link in your pocket.

What I am not looking for is a way to make this a 100% unbeatable security system with facial recognition, DNA scan, mind probe, and thor shots on stand-by. I also don't expect this to be the be-all and end-all of security. I'm just looking for a reasonable and cost-effective SR solution.

This seems like reasonably good, and very cheap security, I'm just looking for the crunchy bits that make it work.

Thanks.