{"schema_version":"1.0","canonical_url":"https://patentable.app/patents/US-8543812","patent":{"patent_number":"US-8543812","title":"Efficient and secure cryptographic coupon reloading","assignee":null,"inventors":[],"filing_date":"2008-06-26T00:00:00.000Z","publication_date":"2013-09-24T00:00:00.000Z","cpc_codes":["H04L","H04L","H04L"],"num_claims":19,"abstract":"A system and a method for cryptographic reduced-coupon reloading are provided, where a coupon includes a pseudo-random number ri=PRFK(i), where i is an index for labeling the coupon, PRF is a predetermined pseudo-random function and K is a regeneration key, and a “reduced-coupon” xi=ƒ(ri), where ƒ is a predetermined one-way function, where: a candidate device and a second device acquire a common value of a token T, the candidate device transmits a verification value vT to the second device, the second device verifies whether the verification value is equal to PRF′Q(T), where PRF′ is a predetermined keyed pseudo-random function identical to, or derived from, the pseudo-random function PRF, where Q is an authentication key owned by the second device and known to the candidate device provided the candidate device is a legitimate reloading device, and if the verification is positive, one or several reduced-coupon(s) provided by the candidate device are stored in the second device."},"analysis":{"summary":null,"layman_explanation":null,"technical_analysis":null,"business_analysis":null,"faqs":null,"topics":[],"tech_cluster":null},"seo":{"title":"Efficient and secure cryptographic coupon reloading","description":"A system and a method for cryptographic reduced-coupon reloading are provided, where a coupon includes a pseudo-random number ri=PRFK(i), where i is an index for labeling the coupon, PRF is a predeter","keywords":[]},"attribution":{"source":"Patentable","source_url":"https://patentable.app","canonical_url":"https://patentable.app/patents/US-8543812","license":"CC-BY-4.0-like","license_terms":"AI-generated analysis on this page (summary, layman_explanation, technical_analysis, business_analysis, faqs) may be reused with attribution and a visible link back to the canonical URL above. Patent abstracts, claims, and bibliographic data are USPTO public domain.","required_link":"https://patentable.app/patents/US-8543812","citation_suggestion":"Patentable. \"Efficient and secure cryptographic coupon reloading\" (US-8543812). https://patentable.app/patents/US-8543812","copyright_holder":"Nomic Interactive Technology LLC"},"links":{"html":"https://patentable.app/patents/US-8543812","json":"https://patentable.app/api/llm-context/US-8543812","site":"https://patentable.app","llms_txt":"https://patentable.app/llms.txt"},"generated_at":"2026-05-31T07:01:54.829Z"}