Journal ArticleDOI
Private information retrieval
TLDR
This work describes schemes that enable a user to access k replicated copies of a database and privately retrieve information stored in the database, so that each individual server gets no information on the identity of the item retrieved by the user.Abstract:
Publicly accessible databases are an indispensable resource for retrieving up-to-date information. But they also pose a significant risk to the privacy of the user, since a curious database operator can follow the user's queries and infer what the user is after. Indeed, in cases where the users' intentions are to be kept secret, users are often cautious about accessing the database. It can be shown that when accessing a single database, to completely guarantee the privacy of the user, the whole database should be down-loaded; namely n bits should be communicated (where n is the number of bits in the database).In this work, we investigate whether by replicating the database, more efficient solutions to the private retrieval problem can be obtained. We describe schemes that enable a user to access k replicated copies of a database (k≥2) and privately retrieve information stored in the database. This means that each individual server (holding a replicated copy of the database) gets no information on the identity of the item retrieved by the user. Our schemes use the replication to gain substantial saving. In particular, we present a two-server scheme with communication complexity O(n1/3).read more
Citations
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The Sybil Attack
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Freenet: a distributed anonymous information storage and retrieval system
TL;DR: Freenet as discussed by the authors is an adaptive peer-to-peer network application that permits the publication, replication, and retrieval of data while protecting the anonymity of both authors and readers, but it does not provide any centralized location index.
References
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Book
Information Theory and Reliable Communication
TL;DR: This chapter discusses Coding for Discrete Sources, Techniques for Coding and Decoding, and Source Coding with a Fidelity Criterion.
Book
Cryptography and data security
TL;DR: The goal of this book is to introduce the mathematical principles of data security and to show how these principles apply to operating systems, database systems, and computer networks.
On data banks and privacy homomorphisms
TL;DR: It appears likely that there exist encryption functions which permit encrypted data to be operated on without preliminary decryption of the operands, for many sets of interesting operations.
Journal ArticleDOI
Software protection and simulation on oblivious RAMs
Oded Goldreich,Rafail Ostrovsky +1 more
TL;DR: This paper shows how to do an on-line simulation of an arbitrary RAM by a probabilistic oblivious RAM with a polylogaithmic slowdown in the running time, and shows that a logarithmic slowdown is a lower bound.