Cryptology ePrint Archive: Report 2007/005

Privacy-Protecting Coupon System Revisited

Lan Nguyen

Abstract: At FC’05, Chen et al. introduced an elegant privacy protecting coupon (PPC) system, CESSS05, in which users can purchase multi-coupons and redeem them unlinkably while being prevented from overspending or sharing the coupons. However, the costs for issuing and redeeming coupons are linear to the redeeming limit. Security of the system is not proved and only some arguments on system properties are provided. Coupons last indefinitely and can not be terminated. In this paper, we propose the first PPC system with constant costs for communication and computation. Coupons are revokable and the system is provably secure.

Category / Keywords: cryptographic protocols / coupon, anonymity, privacy

Publication Info: Updated version of the paper published in Financial Cryptography 2006

Date: received 4 Jan 2007

Contact author: Lan Nguyen at winmagic com

Available formats: PDF | BibTeX Citation

Version: 20070107:114531 (All versions of this report)

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