A Practical Oblivious Map Data Structure with Secure Deletion and History Independence [article]

Daniel S. Roche, Adam J. Aviv, Seung Geol Choi
2015 arXiv   pre-print
We present a new oblivious RAM that supports variable-sized storage blocks (vORAM), which is the first ORAM to allow varying block sizes without trivial padding. We also present a new history-independent data structure (a HIRB tree) that can be stored within a vORAM. Together, this construction provides an efficient and practical oblivious data structure (ODS) for a key/value map, and goes further to provide an additional privacy guarantee as compared to prior ODS maps: even upon client
more » ... se, deleted data and the history of old operations remain hidden to the attacker. We implement and measure the performance of our system using Amazon Web Services, and the single-operation time for a realistic database (up to 2^18 entries) is less than 1 second. This represents a 100x speed-up compared to the current best oblivious map data structure (which provides neither secure deletion nor history independence) by Wang et al. (CCS 14).
arXiv:1505.07391v2 fatcat:sd4x6fofsndh5f3oxjj6mbjnd4