Oblivious Assignment with m Slots

Preserving anonymity and privacy of customer actions within a complex software system, such as a cloud computing system, is one of the main issues to be solved in order to boost private computation outsourcing. In this paper, we propose a coordination paradigm, namely oblivious assignment with m slots of a resource R (with m ≥ 1), allowing processes to compete in order to get a slot of R, while ensuring at the same time both fairness in the resource slots assignment and that no process knows which slot of R is assigned to a process. We study oblivious assignment with m slots solvability issues related to the message pattern of the algorithm. We also present a distributed algorithm solving oblivious assignment with m slots within a distributed systems, assuming the existence of at least two honest processes and m ≤ n (where n is the number of processes). The algorithm is based on a rotating token paradigm and employs an adaptation of the ElGamal encryption scheme to work with multiple parties and ensuring obliviousness of the assignment. Finally, the correctness of the algorithm is formally proved.