What technique will provide the greatest assurance against unauthorized access with a stolen or cloned access badge?

Requiring a PIN along with the badge provides an additional layer of security that significantly enhances protection against unauthorized access, especially in the event that an access badge is stolen or cloned. The use of a PIN means that even if an intruder possesses the physical badge, they would still need to know the associated PIN to gain access. This two-factor authentication approach—something you have (the badge) combined with something you know (the PIN)—greatly reduces the likelihood of unauthorized access.

This method ensures that possession of just the badge is insufficient for entry, which is a crucial defense against scenarios where a badge is lost or duplicated. Other techniques might add security or help verify identity, but they do not provide the same dual-layer protection that combining a badge with a PIN does.