Access Control: What is it

What is Access Control?

Access Control Concept
Access Control Concept

Access control is anything that is used to prevent the wrong people from gaining access to your secure area. A door lock and key control access. If you have a dog in your yard, with a big sign that says, “Beware of Dog!” You have access control. Access control always includes a key to allow entry. The dog only lets in the people it knows, so that’s the key.

In the security world, we refer to access control as a combination of electric lock, a door reader, and a controller that is used to prevent unauthorized entry. Credentials, like a card, are used to identify the right person who can enter the door. The access control system determines who can open a specific door at a scheduled time and date. Rather than have the same key, each person has their own unique key in the form of a credential (card or keyFob).

Access Control History

Old Door Lock

The history books say that the first locks were developed over 6,000 years ago in ancient Assyria, and were perfected in Egypt. These locks and associated keys were made from wood. Metal locks were introduced around 870 AD, and in the 1800s the modern lock became available. In 1778, Robert Barron invented the lever tumbler lock, which used a set of levers to prevent the bolt from moving in the lock. It was the first lock to use pins and tumblers. Jeremiah Chubb improved the lever tumbler lock in 1818.

The electric lock was developed in 1970. This was the beginning of modern door access control technology. The electric locks used a magnet to secure the door or an electric strike to move the strike portion of the door lock. The door reader controls the lock and uses a separate access controller box to control all the readers. The early door readers used bar codes, Wiegand coding, or magnetic strips to provide an ID number for each credential.

Today the door readers work with proximity or RFID credentials or use biometrics for the key. To learn more about the history of access control, see our video, How Biometric Readers Work.

Access Control Components

Access control systems consist of:

  1. An electric lock
  2. Access control door reader that controls the electric lock
  3. A credential that holds the unique ID number associated with each person
  4. A controller that provides the intelligence and control of the electric lock
  5. Access Control Management Software that manages all the users

Electric Lock

Electric Lock

An electric lock is usually implemented as a magnetic lock or as an electric strike.

Magnetic locks are used in high-security areas where you need to monitor the movement of people. Since people are required to use their access cards in both directions, you can track who enters and leaves a secure area.

Electric strikes are easy to install and are used to secure outer and inner doors, but do not prevent egress from an area like the magnetic lock. It replaces the fixed strike place in a standard lock.

To learn more about electric locks, see our lock descriptions.

Access Control Door Reader

The door reader enables the ”key” part of door access by reading the credentials. The door reader is designed to read specific credentials. The credential passes the unique ID number to the reader. Once the credential is read by the reader, the ID information Is compared to a list of allowed ID numbers. If it is valid, the door is opened.

Door readers are either network-attached and include a built-in controller or are slave-type that are designed to be connected to a separate controller. The network-attached type readers are intelligent and are referred to as IP door readers. The Isonas IP readers and the biometric IP readers are examples of network-attached smart readers. Wiegand connected readers are examples of slave-type door readers that connect to a controller.

Door Access Credential

Door Access Reader
Door Access Reader

The credential can be in the form of a thin card, thick card, or keyFob. The credential communicates with the door reader using Radio Frequency ID (RFID) transport. It can use different coding and protocols such as HID or smart card technology. There are also credentials that are provided by a smartphone. These mobile credentials use either Bluetooth or near field communication (NFC) to communicate with the door reader. The credential and the reader must always be matched. When you purchase a specific door access reader, you need to make sure that the credential is compatible.  To learn more about credentials, look at our article, Comparison of Door Access Credentials.

Access Controller

The access controller provides the intelligence to control the door reader. It maintains a list of users and the rules that control when, where, and who can enter a door.

The controller can be included within the reader, like the Isonas reader/controller, or it can be in a separate box like the Hartmann controller system. The Hartmann controller can be located at the door, or it can be placed in a central location and control many doors.

Access Control Management Software

The access control management software makes it easy to enter and edit all the users of the system. It allows the administrator to enter the rules for each person. It determines who can enter, what time they can enter, and the doors they can use.

The access control software provides an easy way to add the credential number for each person. The ID number can be entered manually or by swiping the credential at one of the readers. The person’s name, their privilege level, maybe their picture, and other information are entered at this time.

Access Control Management Software
Access Control Management Software

Each individual can be assigned to specific groups. For example, office workers can enter the front door only from 9 am to 5 pm. The management team can enter through the front or back door, and can enter anytime between 8 am and 10 pm. The security person can open any door at any time. All this is controlled by setting up access privilege groups and then assigning the people to each of the groups.

Access Control Summary

An access control system includes an electric lock, door reader, credential, access control software. The system controls who can enter, when they can get in, and what doors they can use. The system can be integrated with IP camera systems and intercoms to provide increased safety and security.


If you would like help selecting your access control system, please contact us at 1-800-431-1658 in the USA, or at 914-944-3425 everywhere else, or use our contact form.