Access Control Explained: Credentials, Readers and Controllers

Who can go where and when, with a record of every attempt.

An access control system checks a credential (card, PIN, fingerprint, face or phone) at a reader. A controller decides, then a lock opens or stays closed, and the event is logged.

• Software manages users, permissions, schedules and visitor passes
• Alarms for forced doors and doors held open
• IoT angle: stream events by API or MQTT and raise a service ticket when a reader or lock goes offline
• Link entry events to CCTV for instant video context

On a fire alarm, magnetic locks must release so people can leave. This is certified, fail-safe wiring, not a software feature.