Proactive security provides a method for maintaining the overall security of a system,even when individual components are repeatedly broken into and controlled by an attacker. Proactive security is a non-trivial exten...Proactive security provides a method for maintaining the overall security of a system,even when individual components are repeatedly broken into and controlled by an attacker. Proactive security is a non-trivial extension of (t＋1,n)-threshold cryptosystems,where shares are periodically renewed (without changing the secret) in such a way that information gained by the adversary in one time period is useless for attacking the secret after the shares are renewed. In this paper,we describe the proactive approach and review some basic technologies. We also report the problems need to be study.展开更多
E-lottery is a popular game for its convenience provided by the Internet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only...E-lottery is a popular game for its convenience provided by the Internet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only provide seed numbers to create the initial value of the lucky number, but also have an opportunity to change the intermediate value of the lucky number by means of voting. The new property of the scheme makes the lottery game more interactive and attractive to players. The anonymity of submitting the lottery ticket and casting the vote is achieved. Comparison with other existing e-lottery schemes is given.展开更多
As e-commerce applications and the underlying public key infrastructure have become more popular over time,many digital mechanisms emulating traditional business activities have been developed and deployed. To build a...As e-commerce applications and the underlying public key infrastructure have become more popular over time,many digital mechanisms emulating traditional business activities have been developed and deployed. To build a full-fledgedsecure digital world,secure implementations of more commercial activity primitives are required. In this paper,we present asecure proxy signature scheme and its threshold version based on the homomorphic Paillier cryptosystem,which can be used inmany e-commerce applications such as e-voting,e-bidding/auction,and privacy-preserving data mining. These two schemes areexistentially unforgeable against chosen-message attacks and chosen-warrant attacks in the random oracle model. Although it isbased on factoring,the threshold Paillier proxy scheme operates without requiring any trusted dealer or combiner. Thus,these twoschemes are practical for integration in modularized secure multi-party protocols.展开更多
文摘Proactive security provides a method for maintaining the overall security of a system,even when individual components are repeatedly broken into and controlled by an attacker. Proactive security is a non-trivial extension of (t＋1,n)-threshold cryptosystems,where shares are periodically renewed (without changing the secret) in such a way that information gained by the adversary in one time period is useless for attacking the secret after the shares are renewed. In this paper,we describe the proactive approach and review some basic technologies. We also report the problems need to be study.
文摘E-lottery is a popular game for its convenience provided by the Internet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only provide seed numbers to create the initial value of the lucky number, but also have an opportunity to change the intermediate value of the lucky number by means of voting. The new property of the scheme makes the lottery game more interactive and attractive to players. The anonymity of submitting the lottery ticket and casting the vote is achieved. Comparison with other existing e-lottery schemes is given.
文摘As e-commerce applications and the underlying public key infrastructure have become more popular over time,many digital mechanisms emulating traditional business activities have been developed and deployed. To build a full-fledgedsecure digital world,secure implementations of more commercial activity primitives are required. In this paper,we present asecure proxy signature scheme and its threshold version based on the homomorphic Paillier cryptosystem,which can be used inmany e-commerce applications such as e-voting,e-bidding/auction,and privacy-preserving data mining. These two schemes areexistentially unforgeable against chosen-message attacks and chosen-warrant attacks in the random oracle model. Although it isbased on factoring,the threshold Paillier proxy scheme operates without requiring any trusted dealer or combiner. Thus,these twoschemes are practical for integration in modularized secure multi-party protocols.
