Access control systems tend to be logic controlled systems that can be programmed to allow doors, gates, roller doors, safes etc to be accessed under specific guidelines. Specific guidelines and rules often include who can pass, at what time can they pass and what areas can they enter.
Inputs: The way to request passage and entry is via some type of input. An input can be as simple as a keyswitch or maybe more secure using a codepad with pin code, or higher security using a special encrypted card reader often called a proximity reader, or perhaps a biometric reader that scans your eye or finger. The best security may involve a combination of inputs like proximity card and also pin code, or eye scan and keyswitch etc.
Controller: A controller is the heart and brains that runs the inputs and outputs. Most commonly controllers come in single 1 door models, 2 door models or 4 door models. To get more doors controlled you often simply combine a number of controllers. These controllers are commonly used in airports, buildings, warehouses, factories, offices, banks, and on gates etc.
Outputs: Once an input is triggered it passes the information to the controller and it is the controller that determines if you have access privileges and if so then the output is triggered. An output device may be the opening of an electronic lock, or gate, etc.
Access Privileges: The success of access control systems is determined by the access privileges provided to users. The easy way to setup access is to let everyone be able to pass everywhere at all times but easy is not good for security. You decide if convenience or security is your goal or compromise on both.
Spend time working out the critical areas with the most security required for example the vault or high risk or unsafe areas. once you decide the most secure areas you determine the least number of people that need access to those areas and work backwards to other areas adding more people as needed to less sensitive less secure areas.
Happy hunting, searching, buying, installing or repairing.
Source by Ric Mejias