I would like to install lockers in a wide area—specifically, around a football or soccer pitch. The lockers would have no electricity and would be standalone, so the RFID locks would need to have batteries. I see that there are RFID tags in the shape of wristbands or bracelets, which I would like to offer as the key. How would a bracelet know that it has already been used to lock a locker and cannot lock another one without unlocking the first lock? Is some information about the lock stored on the key?
Each RFID-enabled lock must be connected to the internet or set up to open only when an RFID tag containing a specific serial number is interrogated. In the case of readers programed to open only when a specific tag is read, you would make only one wristband containing a tag with the serial number 1234567890 and one locker with an RFID-enabled lock that would open when that tag is read.
This option should be used only if no internet access is available, as it would greatly limit your flexibility. If a customer were to lose the wristband with tag serial number 1234567890, for example, you wouldn't be able to use that locker until you obtained a replacement. Moreover, if someone were to figure out your numbering scheme, he or she could create a tag with the same serial number and get access to the locker for free.
It would be far better to have tags with serial numbers encoded and then program the lock to open when a specific serial number is presented. So today, locker 123 might be opened by serial number 1234567890, but tomorrow you might program locker 456 to open with that tag. If the system were ever hacked, you could change the tag serial numbers and reprogram the readers.
In your case, not having power might mean not having a network connection, since such a connection would consumer power and greatly reduce battery life. So the first option might be your only option.
I hope this answers your question.
—Mark Roberti, Founder and Editor, RFID Journal
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