Towards Practical Oblivious RAM

Emil Stefanov; Elaine Shi; Dawn Song

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arXiv · 1106.3652

Towards Practical Oblivious RAM

Emil Stefanov·Elaine Shi·Dawn Song

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Abstract

We take an important step forward in making Oblivious RAM (O-RAM) practical. We propose an O-RAM construction achieving an amortized overhead of 20X-35X (for an O-RAM roughly 1 terabyte in size), about 63 times faster than the best existing scheme. On the theoretic front, we propose a fundamentally novel technique for constructing Oblivious RAMs: specifically, we partition a bigger O-RAM into smaller O-RAMs, and employ a background eviction technique to obliviously evict blocks from the client-side cache into a randomly assigned server-side partition. This novel technique is the key to achieving the gains in practical performance.

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BibTeX RIS

Emil Stefanov, Elaine Shi, Dawn Song. 2012-12-18. Towards Practical Oblivious RAM. https://arxiv.org/abs/1106.3652

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