Help❓ Admin base kick turret?

I was on a server today that had a "turret" over there admin base, it wasnt actually anything but what it apparantly did was scan whoever was in the base and if you werent "whitelisted" so to say, it would kick you off and send you back to the coast.

Anyone know how the hell they did this and how i could do it on my own server?

I believe that the TSW anti-hack has something like that.