Document Type : Research Article


1 Ferdowsi University of Mashhad, Department of Mathematical Sciences, Mashhad, Iran

2 Sharif University of Technology, Department of Mathematical Sciences, Tehran, Iran


We propose a new online sortition protocol which is decentralized. We argue that our protocol has safety, fairness, randomness, non-reputation and openness properties. Sortition is a process that makes random decision and it is used in competitions and lotteries to determine who is the winner. In the real world, sortition is simply done using a lottery machine and all the participant can be sure about the safety, fairness, randomness, non-reputation, and openness properties. But how we can do the sortition in virtual world such that it satisfies the desired properties? The idea is decentralization. Using cryptography notions, we provide a protocol where all agents participate in computing the winner of sortition. Our proposed protocol is novel and completely differs from other sortition protocols and also it is decentralized. It is simple and easily can be implemented and find the commercial use for those markets who want to give present to their customers in a fair and clear manner.


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