Anti-Passback (APB)

A PACS security policy that prevents a cardholder from re-entering a controlled area (or exiting) without first having performed the opposite movement — typically used to stop badge sharing or piggybacking. Hard APB denies the re-entry attempt outright; soft APB logs the violation but admits the cardholder; timed APB allows re-entry only after a defined cooldown.

AE Guardian doesn't enforce APB itself — it's a property of the PACS that AE provisions against. But Guardian must respect APB-related metadata when provisioning visitor badges, temporary access, and post-exit reactivations. Misconfigured APB is a frequent source of "I can't get back in" tickets at large enterprises.

Implementation across vendors varies: CCURE 9000 supports site-level APB configuration in Clearances; Lenel OnGuard supports per-reader APB modes; AMAG implements APB through Reader Group configuration; PACOM's GAG/FAG access model can layer APB at the area or floor level.