I am storing information on a passive chip and would like to have that data encrypted when it is sent to a reader. Would this be possible? Would a passive chip have the capability to encrypt data when activated by the reader? If so, how could this be accomplished?
Passive RFID transponders generally lack the capability of encrypting data that will be transmitted to a reader. Having said that, why not simply store the encrypted data on a tag, retrieve the encrypted information and then decrypt it? Wouldn’t that achieve the same thing? In fact, it would be more secure since the tag data would be encrypted, so if it were ever read without authorization, the hacker would receive only encrypted data.
In addition, NXP Semiconductors‘ new Ucode DNA chip provides enhanced security, which might work for your purposes (see NXP Releases IC for Secure Encrypted UHF Reads). The chip, designed in accordance with GS1‘s ultrahigh-frequency (UHF) RFID Gen2v2 standards, features cryptographic authentication, based on ISO/IEC 29167-10.
Each time a tag containing a Ucode DNA chip is interrogated, it generates a new crypto key that the reader receives. The device verifies that key, either by accessing a cloud-based service or by using its own firmware. The reader can then confirm whether the tag is legitimate or a clone. The tag can also reply with a randomized response, which the interrogator must decrypt in order to receive the tag ID and access the tag’s user memory. The information is still transmitted without encryption, but a hacker would have a harder time getting access to it on the tag.
—Mark Roberti, Founder and Editor, RFID Journal
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