H. Afzali; H. Nemati; R. Azmi
Abstract
Nowadays, users of information systems have inclination to use a central server to decrease data transferring and maintenance costs. Since such a system is not so trustworthy, users' data usually upkeeps encrypted. However, encryption is not a nostrum for security problems and cannot guarantee the data ...
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Nowadays, users of information systems have inclination to use a central server to decrease data transferring and maintenance costs. Since such a system is not so trustworthy, users' data usually upkeeps encrypted. However, encryption is not a nostrum for security problems and cannot guarantee the data security. In other words, there are some techniques that can endanger security of encrypted data. Majority of existing methods for encrypted data management have some critical defects such as cryptanalysis attacks, encryption/decryption overhead, and inefficient data storing and retrieval. In this paper, at first we propose a prototype model of private key based search on encrypted data. Then we try to improve it significantly to meet security requirements. Our main goal is to offer a practical method of querying arbitrary words on encrypted data using a minimal trust model. Moreover, we present a model for balancing between performance and security based on user's requirements. In comparison with other methods, query response time is improved and the probability of statistical deductions is reduced.
S. Soltani; M. A. Hadavi; R. Jalili
Abstract
Database outsourcing is an idea to eliminate the burden of database management from organizations. Since data is a critical asset of organizations, preserving its privacy from outside adversary and untrusted server should be warranted. In this paper, we present a distributed scheme based on storing shares ...
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Database outsourcing is an idea to eliminate the burden of database management from organizations. Since data is a critical asset of organizations, preserving its privacy from outside adversary and untrusted server should be warranted. In this paper, we present a distributed scheme based on storing shares of data on different servers and separating indexes from data on a distinct server. Shamir's secret sharing scheme is used for distributing data to data share servers. A B+-tree index on the order preserved encrypted values for each searchable attribute is stored in the index server. To process a query, the client receives responses including record numbers from the index server and asks these records from data share servers. The final result is computed by the client using data shares. While the proposed approach is secure against different database attacks, it supports exact match, range, aggregation, and pattern matching queries efficiently. Simulation results show the prominence of our approach in comparison with the bucketing scheme as it imposes lower computation and communication costs on the client.