TIME ATTENDANCE & ACCESS CONTROL
A Geographical access control may be enforced by personnel (e.g., border guard, bouncer, ticket
checker), or with a device such as a turnstile. There may be fences to avoid circumventing this access
control. An alternative of access control in the strict sense (physically controlling access itself) is a
system of checking authorized presence, see e.g. Ticket controller (transportation). A variant is exit
control, e.g. of a shop (checkout) or a country.
The term access control refers to the practice of restricting entrance to a property, a building, or a
room to authorized persons. Physical access control can be achieved by a human (a guard, bouncer, or
receptionist), through mechanical means such as locks and keys, or through technological means
such as access control systems like the mantrap. Within these environments, physical key management
may also be employed as a means of further managing and monitoring access to mechanically
keyed areas or access to certain small assets.
Physical access control is a matter of who, where, and when. An access control system determines
who is allowed to enter or exit, where they are allowed to exit or enter, and when they are allowed to
enter or exit. Historically, this was partially accomplished through keys and locks. When a door is
locked, only someone with a key can enter through the door, depending on how the lock is
configured. Mechanical locks and keys do not allow restriction of the key holder to specific times or
dates. Mechanical locks and keys do not provide records of the key used on any specific door, and
the keys can be easily copied or transferred to an unauthorized person. When a mechanical key is lost
or the key holder is no longer authorized to use the protected area, the locks must be re-keyed.
Electronic access control uses computers to solve the limitations of mechanical locks and keys.
A wide range of credentials can be used to replace mechanical keys. The electronic access control
system grants access based on the credential presented. When access is granted, the door is
unlocked for a predetermined time and the transaction is recorded. When access is refused, the door
remains locked and the attempted access is recorded. The system will also monitor the door and
alarm if the door is forced open or held open too long after being unlocked.