The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 2014
Filed:
Dec. 19, 2012
University of Washington, Seattle, WA (US);
Radha Poovendran, Seattle, WA (US);
Basel Alomair, Kirkland, WA (US);
Andrew Clark, Bellevue, WA (US);
Jorge Cuellar, Baierbrunn, DE;
University of Washington, Seattle, WA (US);
Abstract
A protocol with constant-time complexity solves the problem of private identification of tags in low-cost, large-scale radio frequency identification (RFID) systems—assuming that an adversary has complete control over the communication channel. Each RFID tag has an internal counter, c, and is preloaded with a unique pseudonym, ψ, and a secret key, k. A RFID reader attempting to identify and authenticate a tag within its range generates and transmits a random nonce to the RFID tag, which returns a first hash of its current pseudonym and counter, and a second hash that is a function of the secret key. The reader uses the returned data to identify the RFID tag and its secret key by reference to a database and returns other hash values that authenticate the reader to the RFID tag. The most expensive operation that RFID tags are required to perform is a hash function.