Efficient protocols for private database queries

Tushar Kanti Saha*, Mayank, Takeshi Koshiba

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contribution

7 Citations (Scopus)


We consider the problem of processing private database queries over encrypted data in the cloud. To do this, we propose a protocol for conjunctive query and another for disjunctive query processing using somewhat homomorphic encryption in the semi-honest model. In 2016, Kim et al. [IEEE Trans. on Dependable and Secure Comput.] showed an FHE-based query processing with equality conditions over encrypted data. We improve the performance of processing private conjunctive and disjunctive queries with the low-depth equality circuits than Kim et al.’s circuits. To get the low-depth circuits, we modify the packing methods of Saha and Koshiba [APWConCSE 2016] to support an efficient batch computation for our protocols with a few multiplications. Our implementation shows that our protocols work faster than Kim et al.’s protocols for both conjunctive and disjunctive query processing along with a better security level. We are also able to provide security to both attributes and values appeared in the predicate of the conjunctive and disjunctive queries whereas Kim et al. provided the security to the values only.

Original languageEnglish
Title of host publicationData and Applications Security and Privacy XXXI - 31st Annual IFIP WG 11.3 Conference, DBSec 2017, Proceedings
EditorsSencun Zhu, Giovanni Livraga
PublisherSpringer Verlag
Number of pages12
ISBN (Print)9783319611754
Publication statusPublished - 2017
Event31st Annual IFIP WG 11.3 Conference on Data and Applications Security and Privacy, DBSec 2017 - Philadelphia, United States
Duration: 2017 Jul 192017 Jul 21

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume10359 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Other31st Annual IFIP WG 11.3 Conference on Data and Applications Security and Privacy, DBSec 2017
Country/TerritoryUnited States


  • Batch technique
  • Conjunctive
  • Disjunctive
  • Homomorphic Encryption
  • Packing method
  • Private Database Queries

ASJC Scopus subject areas

  • Theoretical Computer Science
  • Computer Science(all)


Dive into the research topics of 'Efficient protocols for private database queries'. Together they form a unique fingerprint.

Cite this