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arXiv · 2008.01765

Bucket Oblivious Sort: An Extremely Simple Oblivious Sort

Gilad Asharov·T-H. Hubert Chan·Kartik Nayak·Rafael Pass·Ling Ren·Elaine Shi
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Abstract

We propose a conceptually simple oblivious sort and oblivious random permutation algorithms called bucket oblivious sort and bucket oblivious random permutation. Bucket oblivious sort uses $6n\log n$ time (measured by the number of memory accesses) and $2Z$ client storage with an error probability exponentially small in $Z$. The above runtime is only $3\times$ slower than a non-oblivious merge sort baseline; for $2^{30}$ elements, it is $5\times$ faster than bitonic sort, the de facto oblivious sorting algorithm in practical implementations.

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Gilad Asharov, T-H. Hubert Chan, Kartik Nayak, Rafael Pass, Ling Ren, Elaine Shi. 2020-08-04. Bucket Oblivious Sort: An Extremely Simple Oblivious Sort. https://arxiv.org/abs/2008.01765

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