Title
Enabling Epsilon-Approximate Querying In Sensor Networks
Abstract
Data approximation is a popular means to support energy-efficient query processing in sensor networks. Conventional data approximation methods require users to specify fixed error bounds a prior to address the trade-off between result accuracy and energy efficiency of queries. We argue that this can be infeasible and inefficient when, as in many real-world scenarios, users are unable to determine in advance what error bounds can lead to affordable cost in query processing. We envision epsilon-approximate querying (EAQ) to bridge the gap. EAQ is a uniform data access scheme underlying various queries in sensor networks. It allows users or query executors to incrementally 'refine' previously obtained approximate data to reach arbitrary accuracy. EAQ not only grants more flexibility to in-network query processing, but also minimizes energy consumption through communicating data upto a just-sufficient level. To enable the EAQ scheme, we propose a novel data shuffling algorithm. The algorithm converts sensed datasets into special representations called multi-version array (MVA). From prefixes of MVA, we can recover approximate versions of the entire dataset, where all individual data items have guaranteed error bounds. The EAQ scheme supports efficient and flexible processing of various queries including spatial window query, value range query, and queries with QoS constraints. The effectiveness and efficiency of the EAQ scheme are evaluated in a real sensor network testbed.
Year
Venue
Keywords
2009
PROCEEDINGS OF THE VLDB ENDOWMENT
sensor network
DocType
Volume
Issue
Journal
2
1
ISSN
Citations 
PageRank 
2150-8097
1
0.36
References 
Authors
0
4
Name
Order
Citations
PageRank
Yu Liu121.06
Jianzhong Li23196304.46
Hong Gao31086120.07
Xiaolin Fang4747.27