A datacenter administrator is designing physical security for a new colocation cage that houses servers containing regulated customer data. The cage has a single door, and the administrator wants to ensure that entry is logged and that two authorized staff members must be present for the door to unlock. Which of the following should the administrator implement to meet these requirements?
Dual custody, also called two-person integrity, requires two valid credentials to be presented before the door unlocks, and the reader's audit trail logs each entry event. This directly satisfies the requirement that two authorized staff be present and that access is recorded for the regulated cage.
Why this answer
The two-person rule requires an access control method that will not unlock for a single credential. Dual custody configuration on a card reader requires two valid presentations and produces an audit trail, meeting both the presence and logging requirements. Other options either authenticate only one person, rely on shared secrets, or provide no reliable electronic logging.
Exam trap
The trap here is confusing anti-tailgating controls like mantraps or door sensors with true two-person integrity, which requires two separate valid authentications before the lock releases.