Lots of times I've stood in the fish bowl of a secure factory waiting for somebody to get to the front desk and let me in. After a while I would call my contact inside and be directed to the "block of wood" door. I think it's something that will always be with us unless like jamil says you issue fobs or cards. Even then you would need a procedure to control those.
Absolute control would need a security center that would monitor all the doors, like a prison. Maybe that's where we are headed with schools.
Absolute control would need a security center that would monitor all the doors, like a prison. Maybe that's where we are headed with schools.