Access control has emerged as an important field of information security as well as physical security. The main purpose of access control is to ensure that resources and places are only accessed by selected people. As a result, the process brings about the term using and entering. Authorization is, therefore, the permission to access these resources. At the same time, login credentials and locks are the two mechanisms that are used to ensure that access control prevails. Access control finds its application in many places including home security systems

Access control and physical security 


There are two ways that can be used to restrict geographical access. First, it can be restricted using people or personnel. Second, it’s possible using devices. Where personnel is used, it involves the physical presence of a ticket checker, bouncer or even boarder guard. As for devices, it involves the use of a turnstile. Fences can also be used where control is to be achieved. In a layman’s language, access control should be understood as the process of restricting people from entering a room, building or even properties. When the concept of access control is introduced, it means determining the people who can exit and enter. In the past, the process used to be carried out using keys and locks. Today, things have changed with the introduction of electronic access control. This makes it possible to introduce a wide variety of credentials. Whenever access is denied or granted, it’s usually recorded. This may be important for future references. Whenever the door is forced to open, the system will coordinate the process with the alarm to notify relevant authorities.

Operation of access control 


The operation of access control is not complicated. There is a reader that checks the credentials provided by the person who wants to access the premise. These credentials in most cases are in the form of numbers. They are often compared to a control panel that consists of a processor that’s very reliable. The numbers that are provided are then compared against a list that is stored in the database. If the numbers match those on the database, access is granted. 

Readers


When it comes to access control, readers are very important. Today, there are many readers in the market. The basic ones include basic readers, semi-intelligent readers, and intelligent readers. Some of these readers are also equipped with other components such as a smart card reader, a camera, and microphone as well as a speaker. It’s also common nowadays to find readers with function and LED buttons.

Common system topologies


Access control systems can be implemented using a number of topologies. The most widely used topologies include serial controllers, serial main and sub-controllers as well as serial main controller and intelligent readers. Others include IP readers and IP controllers. Each of these topologies has their associated benefits and shortcomings. Like we earlier touched, access control has also become an important aspect of computer security. In this case, there are terms such as authorization and authentication. There is also audit and access approval.