Good question. The answer is, it depends. Most RFID tags lack security features. They provide their unique serial number to any interrogator, using the same air interface protocol as the tag. Ultrahigh-frequency (UHF) tags based on EPCglobal‘s second-generation air interface protocol have secure memory blocks, so the tags will always respond with their serial number, but additional data can be written to blocks of memory that can be locked.
NXP Semiconductors‘ Mifare chips support data encryption as the information is being transmitted over the air. Mifare has employed both proprietary and public encryption. The data on the encrypted tag is only accessible via the encryption algorithm, so it cannot be read without proper encryption algorithm access. As the technology proliferates, the need for security will certainly increase, and vendors will no doubt respond with additional security options.
—Mark Roberti, Editor, RFID Journal
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