RSA Keeps RFID Private

RSA Keeps RFID Private: "The blocker tag system is software-based and relies on technology developed by RSA researchers that prevents RFID readers from gathering data from other tags in their immediate vicinity. Without it, any RFID reader could query any tag, enabling retailers or other companies to read the tags on any merchandise a customer may be carrying.
Essentially, the blocker tag system works by tricking readers that all the possible RFID tags are present at a given time. Because RFID readers can communicate with only one tag at a time, when multiple tags reply to a single query, the reader detects a collision."
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"The tag is just the first fruit of the approach we're taking to this," he said. "There's still a good amount of research to be done. We need security on the protocol, the readers and the back end, too. We need a full set of technologies on the table in order to know what's possible."