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Distributed Oblivious RAM for Secure Two-Party Computation [chapter]

Steve Lu, Rafail Ostrovsky
2013 Lecture Notes in Computer Science  
In the heart of our construction is a new Oblivious RAM construction where a client interacts with two non-communicating servers.  ...  Our two-server Oblivious RAM for n reads/writes requires O(n) memory for the servers, O(1) memory for the client, and O(log n) amortized read/write overhead for data access.  ...  In the follow-up paper we have shown how to make garble RAM programs noninteractive with poly-logarithmic communication overhead [28] . In this paper, we showed how to make the overhead logarithmic.  ... 
doi:10.1007/978-3-642-36594-2_22 fatcat:xvo5757svfboplireewndmv3ce

How to Garble RAM Programs? [chapter]

Steve Lu, Rafail Ostrovsky
2013 Lecture Notes in Computer Science  
As an example, our techniques implies the first garbled binary search program (searching over sorted encrypted data stored in a cloud) which is poly-logarithmic in the data size instead of linear.  ...  We stress that we avoid converting the RAM programs into circuits.  ...  Thus, the smaller the client of Oblivious RAM, the more efficient our solution is: in order to achieve poly-log overhead, all Oblivious RAM schemes where client memory is larger than poly-logarithmic (  ... 
doi:10.1007/978-3-642-38348-9_42 fatcat:ykszm343lngqjmyffbjnue5oym

Verifiable Oblivious Storage [chapter]

Daniel Apon, Jonathan Katz, Elaine Shi, Aishwarya Thiruvengadam
2014 Lecture Notes in Computer Science  
Specifically, for large block sizes we can construct a VOS scheme with constant bandwidth per query; further, answering queries requires only poly-logarithmic server computation.  ...  VOS generalizes the notion of Oblivious RAM (ORAM) in that it allows the server to perform computation, and also explicitly considers data integrity and freshness.  ...  [9] , using Verifiable Oblivious Storage (VOS), we can reduce the bandwidth cost to O(β log n/poly log log n) for reads, and O(βλ log n/poly log log n) for writes, with poly-logarithmic server computation  ... 
doi:10.1007/978-3-642-54631-0_8 fatcat:i36n6hbozjhztacet4yxn42mte

Resizable Tree-Based Oblivious RAM [chapter]

Tarik Moataz, Travis Mayberry, Erik-Oliver Blass, Agnes Hui Chan
2015 Lecture Notes in Computer Science  
Recent works on ORAM, e.g., by Shi et al. [17], Stefanov et al. [18], and many derivatives, have proposed new ORAM schemes that are tree-based and have only poly-logarithmic worst-case communication complexity  ...  Although newly proposed, tree-based Oblivious RAM schemes are drastically more efficient than older techniques, they come with a significant drawback: an inherent dependence on a fixed-size database.  ...  Further results show that you can improve communication complexity if poly-logarithmic client memory is acceptable [5, 6, 18] . Gentry et al. [6] optimize Shi et al.  ... 
doi:10.1007/978-3-662-47854-7_9 fatcat:7shj7tmunnf4fgaln62f4wocnq

More is Less: Perfectly Secure Oblivious Algorithms in the Multi-Server Setting [article]

T-H. Hubert Chan and Jonathan Katz and Kartik Nayak and Antigoni Polychroniadou and Elaine Shi
2018 arXiv   pre-print
The problem of Oblivious RAM (ORAM) has traditionally been studied in a single-server setting, but more recently the multi-server setting has also been considered.  ...  In this work, we construct a perfectly secure 3-server ORAM scheme that outperforms the best known single-server scheme by a logarithmic factor.  ...  Abraham et al. and Kushilevitz and Mour, on the other hand, are poly-logarithmic and logarithmic respectively, both in computation and bandwidth blowup.  ... 
arXiv:1809.00825v1 fatcat:srh3i7cyfnhftbghbvhwhad43q

Oblivious Network RAM and Leveraging Parallelism to Achieve Obliviousness [chapter]

Dana Dachman-Soled, Chang Liu, Charalampos Papamanthou, Elaine Shi, Uzi Vishkin
2015 Lecture Notes in Computer Science  
We propose the Oblivious Network RAM model of computation, where a CPU communicates with multiple memory banks, such that the adversary observes only which bank the CPU is communicating with, but not the  ...  We present new constructions for obliviously simulating general or parallel programs in the Network RAM model.  ...  In their work, Goldreich and Ostrovsky showed both a poly-logarithmic upper-bound (commonly referred to as the hierarchical ORAM framework) and a logarithmic lower-bound for ORAM-both under constant CPU  ... 
doi:10.1007/978-3-662-48797-6_15 fatcat:zxmytox75rfzrkobd5errdzzne

Oblivious Network RAM and Leveraging Parallelism to Achieve Obliviousness

Dana Dachman-Soled, Chang Liu, Charalampos Papamanthou, Elaine Shi, Uzi Vishkin
2018 Journal of Cryptology  
We propose the Oblivious Network RAM model of computation, where a CPU communicates with multiple memory banks, such that the adversary observes only which bank the CPU is communicating with, but not the  ...  We present new constructions for obliviously simulating general or parallel programs in the Network RAM model.  ...  In their work, Goldreich and Ostrovsky showed both a poly-logarithmic upper-bound (commonly referred to as the hierarchical ORAM framework) and a logarithmic lower-bound for ORAM-both under constant CPU  ... 
doi:10.1007/s00145-018-9301-4 fatcat:4uu32x765jhafnvyvibflmbgbq

Maliciously Secure Multi-Client ORAM [chapter]

Matteo Maffei, Giulio Malavolta, Manuel Reinert, Dominique Schröder
2017 Lecture Notes in Computer Science  
It is thus an open question whether a natural definition of obliviousness can be enforced in a malicious multi-client setting and, if so, what the communication and computational lower bounds are.  ...  Oblivious RAM (ORAM) has emerged as an enabling technology to secure cloud-based storage services.  ...  Multi-Client Oblivious RAM In a Multi-Client ORAM scheme the parties consist of the data owner O, several clients C 1 , . . . , C k , and the server S.  ... 
doi:10.1007/978-3-319-61204-1_32 fatcat:hlav2s5wtjditpmcojqw6lmp4y

Asymptotically Tight Bounds for Composing ORAM with PIR [chapter]

Ittai Abraham, Christopher W. Fletcher, Kartik Nayak, Benny Pinkas, Ling Ren
2017 Lecture Notes in Computer Science  
Oblivious RAM (ORAM) is a cryptographic primitive that allows a trusted client to outsource storage to an untrusted server while hiding the client's memory access patterns to the server.  ...  Oblivious RAM is a cryptographic primitive that allows a client to privately outsource storage to an untrusted server without revealing any information about its data accesses, i.e., the server learns  ...  Conclusion and Open Problems In this work, we design an Oblivious RAM with sub-logarithmic overhead where the servers only perform XOR operations.  ... 
doi:10.1007/978-3-662-54365-8_5 fatcat:adzojsnhwnan3dlwu57zdyxzoq

Garbled RAM From One-Way Functions

Sanjam Garg, Steve Lu, Rafail Ostrovsky, Alessandra Scafuro
2015 Proceedings of the Forty-Seventh Annual ACM on Symposium on Theory of Computing - STOC '15  
In this paper we provide the first construction with strictly poly-logarithmic overhead in both space and time based only on the minimal and necessary assumption that one-way functions exist.  ...  Towards the goal of avoiding this inefficiency, Lu and Ostrovsky (Eurocrypt 2013) introduced the notion of "garbled RAM" as a method to garble RAM programs directly.  ...  the RAM pogram (up to poly-logarithmic factors), rather than the size of its circuit representation.  ... 
doi:10.1145/2746539.2746593 dblp:conf/stoc/GargLOS15 fatcat:hy3fnzvknvfjxk5zmmnnmpoveq

Secure two-party computation in sublinear (amortized) time

S. Dov Gordon, Jonathan Katz, Vladimir Kolesnikov, Fernando Krell, Tal Malkin, Mariana Raykova, Yevgeniy Vahlis
2012 Proceedings of the 2012 ACM conference on Computer and communications security - CCS '12  
Our protocol applies generic secure two-party computation on top of oblivious RAM (ORAM).  ...  We describe an implementation of this protocol, and evaluate its performance for the task of obliviously searching a database with over 1 million entries.  ...  Oblivious RAM We view an oblivious-RAM (ORAM) construction as a mechanism that simulates read/write access to an underlying (virtual) array D via accesses to some (real) arrayD; "obliviousness" means that  ... 
doi:10.1145/2382196.2382251 dblp:conf/ccs/GordonKKKM0V12 fatcat:jb3gri5gqrd6jfl6wuzq2t3dai

Oblivious Parallel RAM and Applications [chapter]

Elette Boyle, Kai-Min Chung, Rafael Pass
2015 Lecture Notes in Computer Science  
We discuss applications of such a compiler, building upon recent advances relying on Oblivious (sequential) RAM (Goldreich Ostrovsky JACM'12).  ...  We propose and attain the notion of Oblivious PRAM.  ...  Multi-Client Outsourced Data. In a similar vein, use of OPRAM further enables secure access and manipulation of outsourced shared data by multiple (mutually trusting) clients.  ... 
doi:10.1007/978-3-662-49099-0_7 fatcat:hax4sukl6bfnvhcio47p5krile

Oblivious Data Structures

Xiao Shaun Wang, Kartik Nayak, Chang Liu, T-H. Hubert Chan, Elaine Shi, Emil Stefanov, Yan Huang
2014 Proceedings of the 2014 ACM SIGSAC Conference on Computer and Communications Security - CCS '14  
We show that these two techniques are powerful building blocks in making data structures and algorithms oblivious.  ...  Our oblivious counterparts of the above outperform the best known ORAM scheme both asymptotically and in practice.  ...  We remark that under large block sizes, Path ORAM can achieve O(log N ) bandwidth blowup under poly-logarithmic client-side storage -however, the large block size assumption is often not applicable for  ... 
doi:10.1145/2660267.2660314 dblp:conf/ccs/WangNLCSSH14 fatcat:ix3keelbmfcu5cdxt7mgu7w73m

Building castles out of mud

Peter Williams, Radu Sion, Bogdan Carbunar
2008 Proceedings of the 15th ACM conference on Computer and communications security - CCS '08  
Moreover, the client is provided with strong correctness assurances for its operations -illicit provider behavior does not go undetected.  ...  We introduce a new practical mechanism for remote data storage with efficient access pattern privacy and correctness.  ...  RELATED WORK Oblivious RAM Oblivious RAM [14] provides access pattern privacy to clients (or software processes) accessing a remote database (or RAM), requiring only logarithmic storage at the client  ... 
doi:10.1145/1455770.1455790 dblp:conf/ccs/WilliamsSC08 fatcat:57quqjkmwraohoh3akueil32ae

Hardware-Supported ORAM in Effect: Practical Oblivious Search and Update on Very Large Dataset

Thang Hoang, Muslum Ozgur Ozmen, Yeongjin Jang, Attila A. Yavuz
2019 Proceedings on Privacy Enhancing Technologies  
However, due to the logarithmic communication overhead of ORAM, the composition of ORAM and SE is known to be costly in the conventional client-server model, which poses a critical barrier toward its practical  ...  In response to such attacks, the community has proposed the Oblivious Random Access Machine (ORAM).  ...  Despite its merits, ORAM incurs a poly-logarithmic bandwidth blowup [71, 76] , which has been shown to be costly for searchable encryption in the standard client-server network setting [7, 53, 68] .  ... 
doi:10.2478/popets-2019-0010 dblp:journals/popets/HoangOJY19 fatcat:6mztyoztvfa4bh5by3rpyspmky
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