Is this possible?
To answer your question, I reached out to Richard Aufreiter, the director of product management for identification technologies at HID Global, a leading provider of access-control systems. Here is his response:
“Usually, desktop readers are read-write, whereas door-mounted readers are read-only. But in general, it [whether or not writing is possible] depends on the reader model and the way the credential is programmed. If you need more details on particular models, one of my staff can assist you.”
So typically, you would have a desktop reader that would allow you to write information about access privileges to a card for that card holder. But there is no need for door-mounted interrogators to also write to the tags, so most lack this functionality. If you would like to know whether a specific model is read-write, I can try to find out for you (e-mail me at editor [at] rfidjournal.com), or you can call the manufacturer directly.
—Mark Roberti, Founder and Editor, RFID Journal
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