Unlinkable Electronic Coupon Protocol with Anonymity Control

Abstract

Abstract. In a variant of the electronic cash protocol, an electronic coupon protocol, a withdrawn coin is divided into many sub-coins whose face values are fixed in advance, and the sub-coins are only used in payments. The original coin is called ticket and the sub-coins are called sub-tickets. The electronic cash protocol should satisfy not only the anonymity that the payer cannot be traced from the payments, but also the unlinkability. The unlinkability means that anyone cannot determine whether payments were made by the same payer. If the unlinkability does not hold, tracing the payer from one payment leads to tracing the payer from all his/her payments, and the link between the payments also facilitates the de-anonymization. In the previously proposed electronic coupon protocol, payments of sub-tickets derived from the same ticket are linkable. Since the complete anonymity of payments facilitates fraud and criminal acts, the electronic cash protocols should equip the revocation of the anonymity. In this paper, an electronic coupon protocol is proposed, where all payments are unlinkable but the anonymity of the payments can be revoked.

Transferable Constant-Size Fair E-Cash

“…with divisible e-cash [EO94,CG07]. However, for many applications, such as e-tickets or coupons [NHS99], transferability [OO90,OO92,CG08] is a more desirable property. It is known that the size of coins grows linearly in the number of transfers [CP92]-a drawback we will avoid in our construction by modifying the model (cf.…”

PCM: a privacy‐preserving detection mechanism in mobile ad hoc networks

“…Extensive research have been undertaken to allow users to authenticate anonymously within certain number of times in terms of different applications, such as e-voting [49--53], e-cash [54--58], electronic coupon [59,60], and trial browsing of content. However, in order to solve possible disputations at a later time, these schemes are based on identity escrow/group signatures [61--67], and give the group manager or authority the unnecessary ability to trace any user even if there is no disputation.…”

A Fair Electronic Cash System with Identity-Based Group Signature Scheme

“…Many group signatures scheme have been proposed recently, but several of them were suggested application electronic cash. [9][10][11] introduced group signatures into electronic cash schemes which are anonymous and unlinkability.…”