54,596 research outputs found
An Effective Private Data storage and Retrieval System using Secret sharing scheme based on Secure Multi-party Computation
Privacy of the outsourced data is one of the major challenge.Insecurity of
the network environment and untrustworthiness of the service providers are
obstacles of making the database as a service.Collection and storage of
personally identifiable information is a major privacy concern.On-line public
databases and resources pose a significant risk to user privacy, since a
malicious database owner may monitor user queries and infer useful information
about the customer.The challenge in data privacy is to share data with
third-party and at the same time securing the valuable information from
unauthorized access and use by third party.A Private Information Retrieval(PIR)
scheme allows a user to query database while hiding the identity of the data
retrieved.The naive solution for confidentiality is to encrypt data before
outsourcing.Query execution,key management and statistical inference are major
challenges in this case.The proposed system suggests a mechanism for secure
storage and retrieval of private data using the secret sharing technique.The
idea is to develop a mechanism to store private information with a highly
available storage provider which could be accessed from anywhere using queries
while hiding the actual data values from the storage provider.The private
information retrieval system is implemented using Secure Multi-party
Computation(SMC) technique which is based on secret sharing. Multi-party
Computation enable parties to compute some joint function over their private
inputs.The query results are obtained by performing a secure computation on the
shares owned by the different servers.Comment: Data Science & Engineering (ICDSE), 2014 International Conference,
CUSA
Asymmetry Helps: Improved Private Information Retrieval Protocols for Distributed Storage
We consider private information retrieval (PIR) for distributed storage
systems (DSSs) with noncolluding nodes where data is stored using a non maximum
distance separable (MDS) linear code. It was recently shown that if data is
stored using a particular class of non-MDS linear codes, the MDS-PIR capacity,
i.e., the maximum possible PIR rate for MDS-coded DSSs, can be achieved. For
this class of codes, we prove that the PIR capacity is indeed equal to the
MDS-PIR capacity, giving the first family of non-MDS codes for which the PIR
capacity is known. For other codes, we provide asymmetric PIR protocols that
achieve a strictly larger PIR rate compared to existing symmetric PIR
protocols.Comment: To be presented at 2018 IEEE Information Theory Workshop (ITW'18).
See arXiv:1808.09018 for its extended versio
Adaptively Secure Computationally Efficient Searchable Symmetric Encryption
Searchable encryption is a technique that allows a client to store documents on a server in encrypted form. Stored documents can be retrieved selectively while revealing as little information as\ud
possible to the server. In the symmetric searchable encryption domain, the storage and the retrieval are performed by the same client. Most conventional searchable encryption schemes suffer\ud
from two disadvantages.\ud
First, searching the stored documents takes time linear in the size of the database, and/or uses heavy arithmetic operations.\ud
Secondly, the existing schemes do not consider adaptive attackers;\ud
a search-query will reveal information even about documents stored\ud
in the future. If they do consider this, it is at a significant\ud
cost to updates.\ud
In this paper we propose a novel symmetric searchable encryption\ud
scheme that offers searching at constant time in the number of\ud
unique keywords stored on the server. We present two variants of\ud
the basic scheme which differ in the efficiency of search and\ud
update. We show how each scheme could be used in a personal health\ud
record system
What Storage Access Privacy is Achievable with Small Overhead?
Oblivious RAM (ORAM) and private information retrieval (PIR) are classic
cryptographic primitives used to hide the access pattern to data whose storage
has been outsourced to an untrusted server. Unfortunately, both primitives
require considerable overhead compared to plaintext access. For large-scale
storage infrastructure with highly frequent access requests, the degradation in
response time and the exorbitant increase in resource costs incurred by either
ORAM or PIR prevent their usage. In an ideal scenario, a privacy-preserving
storage protocols with small overhead would be implemented for these heavily
trafficked storage systems to avoid negatively impacting either performance
and/or costs. In this work, we study the problem of the best $\mathit{storage\
access\ privacy}\mathit{small\ overhead}\mathit{differential\ privacy\ access}\mathit{oblivious\ access}\epsilon = \Omega(\log n)\epsilon = \Theta(\log n)O(1)\epsilon = \Theta(\log n)O(\log\log n)$
overhead. This construction uses a new oblivious, two-choice hashing scheme
that may be of independent interest.Comment: To appear at PODS'1
GIS Application to Support Land Administration Services in Ghana: Institutional Factors and Software Developments
In June 1999, the Ghanaian Government launched a new land policy document that sought to address some fundamental problems associated with land administration and management in the country. The document identified the weak land administration system as a particular problem and recommended the introduction of computer-aided information systems in the ālands sectorā. In 2001, the Government made further proposals to prepare and implement a Land Administration Programme (LAP) to provide a better platform for evolving an efficient land administration that would translate the āNational Land Policyā into action. Thus, an up-to-date land information system (LIS), supporting efficient management of land records, is to be constructed, which provides a context for the research reported in this paper. We document two aspects of our research on the adoption of GIS by the Lands Commission Secretariat (LCS) which form part of a pilot project in GIS diffusion. Part one of the paper mainly outlines the empirical results arising from fieldwork undertaken during 2001 to determine the information and GIS requirements of the LCS in relation to their routine administrative processes and to identify the critical factors that are required to ensure that any new GIS applications are successfully embraced. Part two explains the prototype software system developed using ArcView 3.2 and Access that provides the LCS with a means to automate some of the routine administrative tasks that they are required to fulfil. The software has been modified and upgraded following an initial evaluation by LCS employees also conducted as part of the fieldwork in Accra
SoK: Cryptographically Protected Database Search
Protected database search systems cryptographically isolate the roles of
reading from, writing to, and administering the database. This separation
limits unnecessary administrator access and protects data in the case of system
breaches. Since protected search was introduced in 2000, the area has grown
rapidly; systems are offered by academia, start-ups, and established companies.
However, there is no best protected search system or set of techniques.
Design of such systems is a balancing act between security, functionality,
performance, and usability. This challenge is made more difficult by ongoing
database specialization, as some users will want the functionality of SQL,
NoSQL, or NewSQL databases. This database evolution will continue, and the
protected search community should be able to quickly provide functionality
consistent with newly invented databases.
At the same time, the community must accurately and clearly characterize the
tradeoffs between different approaches. To address these challenges, we provide
the following contributions:
1) An identification of the important primitive operations across database
paradigms. We find there are a small number of base operations that can be used
and combined to support a large number of database paradigms.
2) An evaluation of the current state of protected search systems in
implementing these base operations. This evaluation describes the main
approaches and tradeoffs for each base operation. Furthermore, it puts
protected search in the context of unprotected search, identifying key gaps in
functionality.
3) An analysis of attacks against protected search for different base
queries.
4) A roadmap and tools for transforming a protected search system into a
protected database, including an open-source performance evaluation platform
and initial user opinions of protected search.Comment: 20 pages, to appear to IEEE Security and Privac
Systematizing Genome Privacy Research: A Privacy-Enhancing Technologies Perspective
Rapid advances in human genomics are enabling researchers to gain a better
understanding of the role of the genome in our health and well-being,
stimulating hope for more effective and cost efficient healthcare. However,
this also prompts a number of security and privacy concerns stemming from the
distinctive characteristics of genomic data. To address them, a new research
community has emerged and produced a large number of publications and
initiatives.
In this paper, we rely on a structured methodology to contextualize and
provide a critical analysis of the current knowledge on privacy-enhancing
technologies used for testing, storing, and sharing genomic data, using a
representative sample of the work published in the past decade. We identify and
discuss limitations, technical challenges, and issues faced by the community,
focusing in particular on those that are inherently tied to the nature of the
problem and are harder for the community alone to address. Finally, we report
on the importance and difficulty of the identified challenges based on an
online survey of genome data privacy expertsComment: To appear in the Proceedings on Privacy Enhancing Technologies
(PoPETs), Vol. 2019, Issue
- ā¦