Anti-passback is a process or software control that prevents a user from allowing someone else to utilize his or her access credential to enter a specific entry point after the user has entered the protected area.
There are a few ways of accomplishing this. One is to make the user scan back out of an area after they have scanned in. Another is to have a timer that prevents the access credential from being used more than once in a certain time period, say 5 minutes.
This can be helpful in situations where you want to have complete knowledge about who is in your space, such as an office setting. It can also be used in parking garages to properly track the amount of time customers spent there.
