International Association
for Cryptologic Research

In this paper, we revisit the private top-κ data aggregation problem. First we formally define the problem\'s security requirements as both data and user privacy goals. To achieve both goals, and to strike a balance between efficiency and functionality, we devise a novel cryptographic construction that comes in two schemes; a fully decentralized simple construction and its practical and semi-decentralized variant. Both schemes are provably secure in the semi-honest model. We analyze the computational and communi- cation complexities of our construction, and show that it is much more efficient than the existing protocols in the literature.