Multiple-bank e-cash (electronic cash) model allows users and merchants to open their accounts at different banks which are monitored by the Center Bank. Some multiple-bank e-cash systems were proposed in recent years. However, prior implementations of multiple-bank e-cash all require the random oracle model idealization in their security analysis. We know some schemes are secure in the random ...

We consider delivering interactive dramas. A viewer interacts with a contents provider by answering multiple-choice questions and the answers to these questions influence the plot of delivered story. All possible plots can be represented by a directed graph such that every plot corresponds to some path of the graph. A delivery should be controlled according to the directed graph such that each ...

With the rapid evolution of intelligent computing and networking technology, security support is a must for the emerging networked embedded systems. As a key building block of the security infrastructure for the networked embedded systems, the design of signature schemes is one of the most critical aspects in the research field of secure networked embedded systems. In this paper, we propose a n...

In a (t, n) threshold proxy signature scheme, an original signer can delegate the signature authority to a proxy group of n member such that t or more than t proxy signers can cooperatively sign messages on behalf of the original signer, but t − 1 or fewer proxy signers cannot generate a valid proxy signature. In this paper, we review the security of C. L. Hsu et al.’s threshold proxy signature...

Blind signatures have been widely adopted to construct untraceable electronic cash systems since they are both unlinkable and unforgeable. Although unlinkability protects the privacy of customers and users, it may be abused by criminals for such purposes as to launder money or to safely get a ransom. The techniques of fair blind signatures are developed to deal with the abuse of unlinkability. ...

In this paper, we present a privacy-protecting off-line electronic cash system which is fair, that is, the transactions are (potentially) traceable by a trusted authority but anonymous otherwise. Our scheme, based on a modification of Brands’restrictive blind signature scheme [2], is significantly more efficient than that of [11], while offering the same functionalities (off-line trusted author...

Blind signature and blind multisignature schemes are useful in protocols that guarantee the anonymity of the participants. In practice, in some cases the electronic messages are to be signed by several signers and an electronic message is first blinded then passed to each of the signers, who then sign it using some special signature scheme such as collective signature protocol. In this paper, w...

In a (t, n) designated verifier threshold proxy signature scheme, an original signer can delegate his/her signing power to n proxy signers such that any t or more out of n proxy signers can sign messages on behalf of the original signer but t− 1 or less of the proxy signers cannot generate a valid proxy signature. Of course, the signature is issued for a designated receiver and therefore only t...

In a proxy signature scheme, a potential signer delegates his capabilities to a proxy signer, who can sign documents on behalf of him. The recipient of the signature verifies both identities: that of the delegator and that of the proxy signer. There are many proposals of proxy signature schemes, but security of them has not been considered in a formal way until the appearance of [2, 8]. If the ...

The threshold proxy signature scheme allows the original signer to delegate a signature authority to the proxy group member to cooperatively sign message on behalf of an original signer. In this paper, we also propose a new scheme which includes the features and benefits of the RSA scheme which is a popular security technique. Also, we will evaluate a security of undeniable threshold proxy sign...