A method for mediator identification using queued history of encrypted user information in an incentive attached peer to peer electronic coupon system
Taiki Shojima, Y. Ikkai, Norihisa Komoda · 2005
An incentive attached peer to peer (P2P) electronic coupon system is proposed in which users forward e-coupons to potential users by providing incentives to mediators. A service provider needs to acquire distribution history by recording it in the e-coupons, since this system is intended for pure P2P communication. This causes problems of dishonestly altering the distribution history. To solve such problems, distribution history is realized in a queue structure. Each element at the initial state consists of dummy UIDs, a secret key, and a digital signature. In recording one's UID, the encrypted UID is enqueued to the queue with a hash value of a dummy UID in the dequeued element, so that malicious users cannot impersonate it. Additionally, a public key queue is applied to generate digital signatures on mobile devices. The availability of the proposed method is evaluated by quantifying risk reduction effects using fault tree analysis (FTA).