Casper*: Query processing for location services without compromising privacy

Chi Yin Chow, Mohamed Mokbel, Walid G. Aref

Research output: Contribution to journalArticle

139 Citations (Scopus)

Abstract

In this article, we present a new privacy-aware query processing framework, Capser*, in which mobile and stationary users can obtain snapshot and/or continuous location-based services without revealing their private location information. In particular, we propose a privacy-aware query processor embedded inside a location-based database server to deal with snapshot and continuous queries based on the knowledge of the user's cloaked location rather than the exact location. Our proposed privacy-aware query processor is completely independent of how we compute the user's cloaked location. In other words, any existing location anonymization algorithms that blur the user's private location into cloaked rectilinear areas can be employed to protect the user's location privacy. We first propose a privacy-aware query processor that not only supports three new privacy-aware query types, but also achieves a trade-off between query processing cost and answer optimality. Then, to improve system scalability of processing continuous privacy-aware queries, we propose a shared execution paradigm that shares query processing among a large number of continuous queries. The proposed scalable paradigm can be tuned through two parameters to trade off between system scalability and answer optimality. Experimental results show that our query processor achieves high quality snapshot and continuous location-based services while supporting queries and/or data with cloaked locations.

Original languageEnglish
Article number24
JournalACM Transactions on Database Systems
Volume34
Issue number4
DOIs
Publication statusPublished - 1 Dec 2009
Externally publishedYes

Fingerprint

Query processing
Location based services
Scalability
Servers
Processing

Keywords

  • Continuous queries
  • Location privacy
  • Location-based services
  • Privacy-aware query processing

ASJC Scopus subject areas

  • Information Systems

Cite this

Casper* : Query processing for location services without compromising privacy. / Chow, Chi Yin; Mokbel, Mohamed; Aref, Walid G.

In: ACM Transactions on Database Systems, Vol. 34, No. 4, 24, 01.12.2009.

Research output: Contribution to journalArticle

@article{bc7914df5d394adba515671bbf8dbfe9,
title = "Casper*: Query processing for location services without compromising privacy",
abstract = "In this article, we present a new privacy-aware query processing framework, Capser*, in which mobile and stationary users can obtain snapshot and/or continuous location-based services without revealing their private location information. In particular, we propose a privacy-aware query processor embedded inside a location-based database server to deal with snapshot and continuous queries based on the knowledge of the user's cloaked location rather than the exact location. Our proposed privacy-aware query processor is completely independent of how we compute the user's cloaked location. In other words, any existing location anonymization algorithms that blur the user's private location into cloaked rectilinear areas can be employed to protect the user's location privacy. We first propose a privacy-aware query processor that not only supports three new privacy-aware query types, but also achieves a trade-off between query processing cost and answer optimality. Then, to improve system scalability of processing continuous privacy-aware queries, we propose a shared execution paradigm that shares query processing among a large number of continuous queries. The proposed scalable paradigm can be tuned through two parameters to trade off between system scalability and answer optimality. Experimental results show that our query processor achieves high quality snapshot and continuous location-based services while supporting queries and/or data with cloaked locations.",
keywords = "Continuous queries, Location privacy, Location-based services, Privacy-aware query processing",
author = "Chow, {Chi Yin} and Mohamed Mokbel and Aref, {Walid G.}",
year = "2009",
month = "12",
day = "1",
doi = "10.1145/1620585.1620591",
language = "English",
volume = "34",
journal = "ACM Transactions on Database Systems",
issn = "0362-5915",
publisher = "Association for Computing Machinery (ACM)",
number = "4",

}

TY - JOUR

T1 - Casper*

T2 - Query processing for location services without compromising privacy

AU - Chow, Chi Yin

AU - Mokbel, Mohamed

AU - Aref, Walid G.

PY - 2009/12/1

Y1 - 2009/12/1

N2 - In this article, we present a new privacy-aware query processing framework, Capser*, in which mobile and stationary users can obtain snapshot and/or continuous location-based services without revealing their private location information. In particular, we propose a privacy-aware query processor embedded inside a location-based database server to deal with snapshot and continuous queries based on the knowledge of the user's cloaked location rather than the exact location. Our proposed privacy-aware query processor is completely independent of how we compute the user's cloaked location. In other words, any existing location anonymization algorithms that blur the user's private location into cloaked rectilinear areas can be employed to protect the user's location privacy. We first propose a privacy-aware query processor that not only supports three new privacy-aware query types, but also achieves a trade-off between query processing cost and answer optimality. Then, to improve system scalability of processing continuous privacy-aware queries, we propose a shared execution paradigm that shares query processing among a large number of continuous queries. The proposed scalable paradigm can be tuned through two parameters to trade off between system scalability and answer optimality. Experimental results show that our query processor achieves high quality snapshot and continuous location-based services while supporting queries and/or data with cloaked locations.

AB - In this article, we present a new privacy-aware query processing framework, Capser*, in which mobile and stationary users can obtain snapshot and/or continuous location-based services without revealing their private location information. In particular, we propose a privacy-aware query processor embedded inside a location-based database server to deal with snapshot and continuous queries based on the knowledge of the user's cloaked location rather than the exact location. Our proposed privacy-aware query processor is completely independent of how we compute the user's cloaked location. In other words, any existing location anonymization algorithms that blur the user's private location into cloaked rectilinear areas can be employed to protect the user's location privacy. We first propose a privacy-aware query processor that not only supports three new privacy-aware query types, but also achieves a trade-off between query processing cost and answer optimality. Then, to improve system scalability of processing continuous privacy-aware queries, we propose a shared execution paradigm that shares query processing among a large number of continuous queries. The proposed scalable paradigm can be tuned through two parameters to trade off between system scalability and answer optimality. Experimental results show that our query processor achieves high quality snapshot and continuous location-based services while supporting queries and/or data with cloaked locations.

KW - Continuous queries

KW - Location privacy

KW - Location-based services

KW - Privacy-aware query processing

UR - http://www.scopus.com/inward/record.url?scp=76149103618&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=76149103618&partnerID=8YFLogxK

U2 - 10.1145/1620585.1620591

DO - 10.1145/1620585.1620591

M3 - Article

AN - SCOPUS:76149103618

VL - 34

JO - ACM Transactions on Database Systems

JF - ACM Transactions on Database Systems

SN - 0362-5915

IS - 4

M1 - 24

ER -