Successful authentication opens the first door and provides access to the entrance room. Once inside the room, the first door automatically closes behind the person, locks, and cannot be opened from inside the room. The other door, which opens into the data center, is also locked. Thus, the person is now trapped in this small room (hence the name, man-trap). The only way out is to successfully pass a second set of authentication controls that restrict access through the door leading to the data center. Typically, this involves multifactor authentication that include using a biometric device. Failure to pass this second set of tests leaves the person in the room until members of the security staff arrive. Man-traps are effective, but expensive. Therefore, they are only used to protect extremely valuable assets.