To answer your question, I reached out to Victor Vega, the director of RFID solutions at NFC chip provider NXP Semiconductors. According to Victor, NFC Type 4 tags have built-in encryption (Crypto-1, AES or 3DES), as well as password protection for the memory. They also have memory-lock options to prohibit unintended changes. As for the type of tag you would require, he says the most popular tag in NXP’s portfolio is the nTag203 model, which does not have encryption. So you could test a simple solution using the ISO 14443 standard.
—Mark Roberti, Founder and Editor, RFID Journal
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