• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1994.11a
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• pp.51-66
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• 1994

A divisible off-line electronic cash system based on cut-and-choose has first been proposed by [OO91] and recently more efficient single term divisible cash system was presented in [EO94] which is based on Brand's scheme [Bra93]. In this paper, we present a different type of single term divisible electronic cash system which is more efficient than previously proposed systems such as [OO91], [YLR93], and [EO94] in the standpoint of the amount of communication, the number of modular multiplications required in the payment transactions, and the storage requirement in the withdrawal protocol. Our scheme is a modified version of [LL93], where the major improvement has been made in its withdrawal transaction to introduce untraceability and multi-spendability. We have borrowed the idea of the withdrawal protocol of our scheme from [EO94] with minor modifications. Transferability in our scheme allows only a finite number of transfer. Our scheme satisfies an the desirable properties of an electronic cash system such as untraceability, divisibility and transferability. In addition, we present a n-spendable cash. The basic idea of extension to multi-spendability has been borrowed from [Bra93] with minor modifications.

• International Commerce and Information Review
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• v.5 no.2
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• pp.19-45
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• 2003

The main issues addressed in this paper are as follows : First, this paper makes a distinction among types of e-money, IC card type versus Network type, open-loop type versus closed-loop type, online type versus offline type and accountable type versus unaccountable type, and analysis the clear and accurate criterion. Second, generally speaking, e-money is a claim on originator of e-money and not legal tender, so, delivery of e-money by itself does not relieve of monetary obligation. Between it is not easy to define e-money, by now there are many definitions of e-money, there is a legal uncertainty accordingly and then it is not easy to find proper law applicable to resolve a particular issue. As a result. many problems relating to e-money would be solved through analogical application of the moot proper law among the laws that apply to the cash, check, credit card, or fund transfer after analyzing type of e-money at issue. This paper studies the methods on diffusion of the utilization of electronic money. To diffuse the usage of electronic money, it need; prerequisitely as a basic conditions independence of electronic money, non-reusability, and anonymity. And also as a additional conditions it need; usability in the offline commerce, transferability, divisibility. And now electronic money is used very actively, but still has many Jaw problems such as protections of consumer, law enforcement, supervisory, etc. So electronic money has called as money, but it is sure that electronic money is not a legal tender. So to facilitate the economic function of the electronic monel it is need to supplement the electronic money in the legal sides.

• Journal of Korea Multimedia Society
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• v.7 no.8
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• pp.1107-1119
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• 2004

There is Electronic-cash system as important payment means in Electronic-commerce and the requirement of electronic cash is independence, transferability, divisibility etc. This is important requirement in DRM to provide contents as a same requirement to contents. Because contents itself can see that requirement of Electronic-cash can be transferred the control of to contents requirement as monetary concept. Can apply equally in reproduction and copy for contents, anonymity user's access etc, and several relations. In this paper, wish to put by value that is equal about Electronic-cash and contents, and apply concept of Electronic-cash through this and present DRM model after examine requirement of Electronic-cash and DRM's requirement. Concept used in this paper left copy use authority to use hierarchic tree structure and endowed anonymity for contents and anonymity about user for anonymous user. Finally, examines and compares and analyzes proposed existing methods.