Common ACS Architecture

A typical PACS is organized in layers, from the software that sets policy down to the hardware at each door.

The main layers

• Management application — where admins define cardholders, access levels, and schedules
• Database — stores configuration, credentials, and event history
• Access controllers — field devices that make real-time decisions
• Readers — mounted at doors to capture credentials
• Door hardware — electric locks, position switches, and request-to-exit devices
• Network — connects the controllers to the management services

How it fits together

The software defines policy; the controllers and door hardware enforce it — even when the network is down.