In the access control system, how can we effectively prevent tailing?

Anti-tailing has always been a difficult problem in access control system. Suggest the following ways:

1) door replacement: install the quick-pass door (or three-roller brake). This method also has shortcomings, such as express doors, which are basically used indoors. The width is only 1375px, only one person can pass through, and it has counting alarm function. If two people pass at the same time, an alarm will be generated. Three-roller gate can be used outdoors, but the preventive effect is not ideal for people who cross it. The installation of three rolling gates is suitable for places with security such as exhibitions.

2) Add in and out card reader. If a person wants to come out after following the cardholder, he must swipe his card to open the access door to prevent stalking. However, when going out, if the tracker and the cardholder go out at the same time, the purpose of truly preventing tracking cannot be achieved.

3) Two-way card reading and double-door interlocking. Double door interlocking can basically solve the problem of trailing, because to open the second door, the first door must be locked, otherwise the second door can't be opened at all. Another troublesome method is to install a camera, that is, to use image processing technology to detect portraits (of course, after collecting images through the camera), but this method is more troublesome and requires a lot of knowledge extension.

4) If the security level is particularly high, you can use full-height doors or more advanced interlocking doors (two doors, people weigh after entering one door, and then the second door is opened) to achieve real anti-tailing; The disadvantage is that this kind of door is very expensive.

Hope to adopt! !