Secure Data Aggregation Protocol In Wireless Sensor Network

Wireless sensor network (WSN) which includes a large number of sensor nodes is a wireless self-organizing and data-centric network. Wireless sensor network with low cost cabling, high stability monitoring, perfect fault-tolerant and remote monitoring are increasingly deployed in security-critical applications, such as military monitoring, environmental monitoring, traffic management and medical treatment .The volume of a sensor node is so small that it has limited power, computation, storage, sensing and communication capabilities. However, it will cost much more energy and be shorter the life-time of WSN if every individual sensor node sends the data collected in the monitoring area without aggregation. Data aggregation technology created to resolve the problem can reduce network's energy consumption, increase data accuracy and improve data collection efficiency. Unfortunately, the general protocols including data aggregation are unsafe and hard to ensure confidentiality and integrity of data when sensor network is deployed in a hostile environment.Firstly, this paper gives a comprehensive survey of secure data aggregation protocols in WSN, and analysis of the performance of each protocol. Secondly, this paper protects data by homomorphic encryption algorithm based on elliptic curve. With the traditional symmetric encryption algorithm, the algorithm uses elliptic curve cryptography which is difficult to be broken. So it can effectively ensure the confidentiality of data. Corresponding to public key cryptographic algorithm, it can save energy consumption because the receiver can aggregate cryptograph directly instead of obtaining explicit terms. Thirdly, this paper will give a new result-checking algorithm and its extension algorithm. The new algorithm translates less data in result-checking phase than existing authentication algorithm. It not only ensures the integrity of data but also reduces energy consumption of the network. Finally, this paper presents a new secure tree-based data aggregation protocol which includes homomorphic encryption algorithm and the new result-checking algorithm. I realize query-dissemination and aggregation-commit phases of the protocol in NS-2 (network simulator version 2) by adding hash function and ECC (elliptic curve cryptography) algorithm in the finite binary field. The performance results show the new protocol is feasible and secure.