in hotels, if you lose your room key card, how are they able to reprogram the new one so it works and the old one doesn’t?

Question

Is there some system that transmits information to your door card reader on what the new key is, or is it something different entirely?

In: 1028

Answer 1

You have card I’d 00002 and card I’d 00003.

They set room 52 to open on card 00002 , you loose 00002, they just tell door 52 to not open on card 00002 and open on card 00003.