Research On Secure Data Aggregation Technology Of Wireless Sensor Networks

Wireless sensor networks (WSNs) have been applied in a wide range including environmentmonitoring, logistics tracking, ecological protection, and so on. Typically, sensors have strictlylimited computation abilities and power resources, and they are also hard to defend against attacks.Data aggregation is one of the most important approaches to alleviate the bottlenecks in WSNs. Itcan not only remove the redundant information, reduce the amount of communication data, but alsoimprove the efficiency and accuracy of data collection. However, data aggregation makes WSNsconfront many new challenges in security performance, such as data integrity, and privacyprotection, etc. If the aggregated data is intercepted or falsified, it will suffer some loss for privacyleaks, wrong decisions of base station, and even cause serious accident. The research of thisdissertation focuses on the key security issues of data aggregation, including data integrity, privacyprotection, etc. This dissertation proposes a family of secure data aggregation schemes in WSNsbased on data slicing technology, symmetric privacy homomorphic technology, homomorphicmessage authentication code technology, and elliptic curve cryptography technology. The securityperformances and the network performances are also analyzed in this dissertation. The contributionsare summarized as follows.To solve the issues of malicious modification and privacy leak of aggregation value during thedata aggregation phase of WSNs, this dissertation proposes a lightweight private data aggregationwith data integrity checking scheme. This scheme first hides the sample data through datadisturbance; then it enhances the privacy efficiency by data slicing and assembling technique.Finally, it converts the data to two-tuples to provide integrity checking by the relevance of binarydata. Its security performance and validity are validated by theoretical analysis and simulationexperiments.To solve the issue of the consuming large energy and delay for hop by hop encryption anddecryption, this dissertation proposes a secure data aggregation scheme for WSNs based onsymmetric homomorphic encryption. It attaches a group of congruent numbers to the sensing datain order to execute integrity checking operated by base station (BS) using Chinese RemainderTheorem (CRT); then it adopts a homomorphic encryption scheme to provide privacy preserving;finally, it computes the hash function-based message authentication codes with time and key as theparameters to satisfy data freshness. The theoretical analysis and simulation results show that the algorithm has good security performances and networks performances.The existing secure data schemes are vulnerable to the chosen message attacks. To solve thisproblem, this dissertation proposes two secure data aggregation schemes based on the homomorphicMAC for the WSNs, which are called SDA-HMAC and SDA-HP respectively. First, they adopt thehomomorphic MAC to check the aggregation data integrity; then they use two differenthomomorphic encryption schemes to ensure the data confidentiality; finally, it computes the hashfunction-based message authentication codes with time and key as the parameters to satisfy datafreshness. This dissertation proves both schemes can defend against ciphertext analysis attacks andchosen message attacks by the approach of provable security. The experimental simulation resultsdenote that both schemes have lower energy consumption, higher data transmission efficiency andmore accurate data aggregation results.The symmetric secure data schemes are vulnerable to the chosen plaintext attacks and nodecompromise attacks. To solve this problem, this dissertation proposes a Secure-Enhanced DataAggregation based on Elliptic Curve Cryptography (SEDA-ECC). The design of SEDA-ECC isbased on the principles of privacy homomorphic encryption (PH) and divide-and-conquer. Anaggregation tree disjoint method is first adopted to divide the tree into three subtrees of similar sizes,and a PH-based aggregation is performed in each subtree to generate an aggregated subtree result.Then the forged result can be identified by the base station (BS) by comparing the aggregated countvalue. Finally, the aggregated result can be calculated by the BS according to the remaining resultsthat have not been forged. Extensive analysis and simulations show that SEDA-ECC can achievethe highest security level on the aggregated result with appropriate energy consumption comparedwith other asymmetric schemes.