Research On Secure Query In Wireless Sensor Networks

Recently, secure query in wireless sensor networks (WSNs) has drawn considerable attentionfrom the research community on issues ranging from theoretical research to practical applications.Meanwhile, several inborn characteristics of WSNs introduce unique challenges for secure andefficient query in WSNs. Range query operation is one kind of vital query in wireless sensornetworks, which asks the sensors to return the sensed data in a specific range. It has beenextensively used in wireless sensor networks and supports various applications especially in eventdetection. However, in some specific applications, it may not only require the detection ofabnormal events in a range query, but also need to preserve the privacy of sensitive data collectedby sensors. Therefore, this dissertation mainly focuses on privacy and integrity preserving rangequery in wireless sensor networks.Based on the study and analysis of existing secure range query protocols in wireless sensornetworks, a privacy and integrity preserving range query protocol, named ZOSR, is proposed inthis dissertation. ZOSR enables storage sensors to process queries correctly while preserving theprivacy of one-dimensional and multi-dimensional sensed data and integrity of query result,which can be detailed as the following five aspects:(1) To the one-dimensional range query, the method of R-D judgment is proposed in ZOSR.It transfers the range judgment into the comparison between data distance with query rangemedian and query range radius, which enables the predication only once.(2) ZOSR protocol adopts variable length of interval to divide sensed data, the storagesensors will be able to make the right range judgment by making a comparison between intervalbound and query range radius, which reduces the query times and further improves the queryefficiency.(3) To preserve privacy, ZOSR protocol converts the above comparison into the judgment onwhether there is an intersection between two Z-O encoding data sets. Without any knowledgeabout the plaintext of sensed data and query range, storage sensors are able to obtain the rangequery result.(4) To preserve the integrity, ZOSR protocol generates integrity verification information by adata structure named verification code chain, which is a joint hash value calculated byneighboring sensed data intervals. Sink can make use of these information to verify whether the query result contains exactly the data items that satisfy the query.(5) To the multi-dimensional range query, ZOSR transfers the multi-dimensional rangequery into the one-dimensional range query by the method of multi-dimensional R-D judgment. Itcalculates distance between multi-dimensional sensed data and the center of multi-dimensionalquery range region, which cuts down the energy and space consumption of sensors greatly.At last, it analyzes the security and conducts performance simulation of ZOSR protocol whichshows greater security and less power consumption.