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The two-dimensional code access control usually has a special micro-xin program, which is used to generate the two-dimensional code for unlocking the access control. Just open the applet, generate the QR code, align the QR code to the door lock's recognizer, and easily open the door. Some friends may question that if the QR code is stolen, will the lock be void? Don't worry about this problem, because every QR code is generated on the fly, and the next time you use it or take a screenshot to others, you can't open the access control, which definitely guarantees the user's security. 
There may also be friends who want to know that since the screenshots are invalid, if there are friends and family to visit, is it still necessary to take the mobile phone to open the door? Of course, the developer of this problem has also been considered. Therefore, some optimizations have been made to the supporting small program for this problem. Visitor registration can be carried out through the small program, so that the visitor can also apply for the QR code in the mobile phone to unlock the access control. Such an emerging access control method can be said to be convenient and quick to play. 
Two-dimensional code access control is a product obtained from in-depth study from the perspectives of safety and convenience. There may be certain deficiencies, but its value is still undeniable. Optimized during market applications, it will become a widely used product in the future.
With the improvement of people's safety awareness, the replacement rate of door locks in recent years is also unprecedented. From the most original key locks, to the later password locks and fingerprint locks, to the facial recognition and pupil recognition locks that have become popular in recent years, they have gradually been widely used. What I want to mention today is a brand new type of door lock, which is as good as the type of door lock mentioned above. It is a two-dimensional code access control.
In the past few years, QR code has penetrated into our lives, scanning code, traveling by car, scanning code payment, etc. Its convenience is recognized by everyone. As long as there is a mobile phone, scanning the QR code can complete what you want. operating. The two-dimensional code access control is the same principle. You don't have to use the key to go home, you don't need to change your password or press the fingerprint. As long as you have a mobile phone, opening the door becomes more convenient than ever.